作者感谢Michael Lacerte的技术支持。 MP-L。承认加拿大研究所高级研究（CIFAR），自然科学和工程研究理事会（NSERC），加拿大的加拿大创新基金会（CFI）全宗de魁北克RECHERCHE - 的性质等技术（FRQNT）的财政支持。这里介绍的设备制造在的CRN2和IMDQ设施，部分资金由NanoQuébec。砷化镓/砷化铝镓基板制造ZR瓦希勒夫斯基在加拿大国家研究理事会微结构科学研究所。 JCL和CB-O。提供财政支持的承认CRSNG FRQNT。

下面描述的制造工序上的砷化镓/砷化铝镓基板的尺寸为1.04 x 1.04厘米。 20个相同的器件制作在衬底上的这个大小。在洁净室中完成所有步骤的过程，并在任何时候都必须使用适当的防护装备。在整个过程中使用去离子水，但被简称为“水”在下面的协议。 1。蚀刻梅萨 该制造步骤的结果， 如图4a所示。 <ol><li>与O 2等离子体等离子灰化样品将在75 W为2分钟，以去除不受欢迎的抵制或有机化合物的任何痕迹。 </li><li>清洁样品声波浴用丙酮（2个）和IPA，每次5分钟。与压缩N 2枪吹干。在整个制造协议，使用声波浴时，应避免使用高功率，以防止损坏GaAs晶片有裂开的倾向。 </li><li>烘烤的样品在烘箱中在125℃下至少15分钟，脱水表面。脱水也可以实现通过将样品在热板上，在180℃下至少5分钟。 </li><li>在热板上，在115℃下进行60秒的旋涂样品与希普利S1818的光致抗蚀剂，在3,500 rpm离心30秒，烘烤。抗蚀剂层应该是大约2.5微米厚。 S1818的使用，因为它是厚的，并受很少的解决方案中使用的蚀刻基板​​步骤1.11。在整个制造过程中，重要的是要避免overbaking光致抗蚀剂，电子束抗蚀剂，以确保在随后的步骤中容易除去。 </li><li>使用光刻掩模对准器和边缘珠掩模以暴露抗蚀剂的样品的外部边缘上。边缘珠掩码由一个1×1厘米铬方形的玻璃板上。使用光的波长为436 nm和暴露的抵抗，持续10秒，15米瓦/平方厘米 。佤velength和功率是固定的，可能会随所使用的机器。调整曝光和显影时间获得适当大小的自定义功能。 </li><li>开发MF-319为2分10秒将样品浸曝光的抗蚀剂。在此步骤中，慢慢地搅动。在水冲洗15秒，压缩的N 2枪吹干。应被删除的边缘珠在此步骤结束时，离开一个1×1厘米的表面具有均匀的厚度的抗蚀剂的样品在中间。边缘珠被删除之前露出台面面具，面罩和样品，从而导致更好的结果之间取得了较好的接触。 </li><li>依然采用了光刻掩模对准，公开抵制使用台面面具和436纳米的光，持续7秒，在15毫瓦/平方厘米2。 </li><li>开发曝光的抗蚀剂将样品浸在MF-319为2分10秒，并缓慢搅拌。 15秒冲洗水和压缩的N 2枪吹干。抵抗remainin，样品克，现在有台面的形状。的抗蚀剂，将保护这一地区的样本在后续步骤中被蚀刻掉。 </li><li>要删除所有痕迹抵制在先前曝光的区域，放置在等离子灰化样品和1分钟暴露的O 2等离子体在75 W. </li><li> H 2 SO 4溶液：H 2 O 2：H 2 O（5时01分55秒）是用来蚀刻的样品。中H 2 O 2和水相结合的适当的比例，然后加入H 2 SO 4。此解决方案是非常活泼的时，首先制备。等待20分钟，然后再进行下列步骤，以避免过腐蚀。 </li><li>蚀刻的样品浸渍在酸溶液中几秒钟，并立即在水中漂洗30秒，使反应停止。过去的样品的表面应被蚀刻硅层掺杂剂和几乎所有的二维电子气，以确保在这些地区的枯竭（SEe 图1）。蚀刻深度可以有所不同，这取决于在基片上。一般来说，对于不同的基片使用，一个34秒的浸泡到所需的蚀刻深度为90-100 nm。然而，重要的是不要过度蚀刻，以避免损坏2DEG。由于刻蚀速率的强烈变化与溶液中的H 2 SO 4和H 2 O 2的比例，以及与蚀刻之前的等待时间时，建议进行蚀刻，由几个浸入5-10秒，而不是一个单一的34秒的蚀刻，和测量用轮廓后，每个蚀刻的蚀刻深度。在此解决方案中的相对慢的蚀刻速率可以很好地控制刻蚀深度。冷却低于室温的蚀刻液可导致蚀刻速率降低。然而，因为它是一个浅蚀刻的蚀刻轮廓是不重要的，不同的蚀刻解决方案也可以使用。 </li><li>剥去抵御1165卸妆将样品浸在65℃3小时。冲洗丙酮和IPA 5分钟。用轮廓测量蚀刻轮廓。 </li></ol> 2。欧姆接触的制作 该制造步骤的结果， 如图4b所示。 <ol><li>清洁样品在声波浴浸泡在丙酮（2×）和IPA，每次5分钟。与压缩N 2枪吹干。 </li><li>烘烤的样品在烘箱中在125℃下进行15分钟至表面脱水。 </li><li>旋涂上与LOR5A在2,500 rpm离心30秒，烘烤，在150℃的热板上10分钟。然后，旋涂在与S1813在5000 rpm离心30秒，烘烤，在110℃的热板上，持续60秒。将所得的抗蚀剂的厚度是〜600 nm和〜1.3微米，分别。用于两种抗蚀剂层，以便在步骤2.10中，将存入的金属剥离。 </li><li>使用光刻掩模对准器和边缘珠掩膜，暴露在抗蚀剂上的外编戈的样品与436纳米的光在15毫瓦/厘米2，持续10秒。 </li><li>开发曝光的抗蚀剂将样品浸在MF-319为2分10秒，同时搅拌顺利。在水冲洗15秒，压缩的N 2枪吹干。 </li><li>仍然使用与欧姆接触掩模光刻掩模对准器，但是这一次，对齐的型态的蚀刻台面的欧姆接触。公开436纳米的光，持续6秒，在15毫瓦/平方厘米2。 </li><li>开发中的抗蚀剂MF-319为2分10秒，在搅拌的同时顺利。在水冲洗15秒，压缩的N 2枪吹干。不再有抵抗将存入所在地区的欧姆接触。的显影剂溶解的LOR 5A的速度比S1813，留下的顶部下方的底切的抗蚀剂层。此档案中的抗蚀剂可以防止在边缘处的抗蚀剂形成壁的金属（在步骤2.10中，将存入），并也将允许容易的removal的剩余的抵制和不良金属。 </li><li>要删除所有痕迹抵制在先前曝光的区域，将在等离子灰化样品和揭露它的O 2等离子体在75瓦的1分钟，重要的是不要让样品在血浆中坐得太久，因为约75纳米/分钟的抗蚀剂进行蚀刻，在此步骤中。 </li><li>删除原生氧化层在GaAs样品浸渍在溶液中的H 2 SO 4：H 2 O（1:5），持续30秒，并在水中漂洗30秒。与压缩N 2枪吹干。应尽快进行，以防止重复出现的原生氧化步骤2.10。 </li><li>使用电子束蒸发沉积镍25纳米，55纳米锗，和80纳米的金。沉积速率分别为0.2纳米/秒，0.5纳米/秒和0.5纳米/秒。沉积速率的选择，使蒸发的时间足够短，以避免加热室不这么短，会失去精度吨的厚度他沉积层。如果它是9，可以由一个单一的共晶GeAu层替换的Ge和Au的双层。 </li><li>的一个步骤中沉积的金属的样品的整个表面上。去除淀积在抗蚀剂上的金属溶解后者。要做到这一点，沉浸于1165卸妆样品在65℃3小时。删除任何不需要的金属，可能不会对自己抬起的，用吸管轻轻一喷样品的表面用热卸妆。每次5分钟，在丙酮和异丙醇淋洗样品。 </li><li>用于甲快速热退火过程中形成的气体扩散沉积的金属的样品的二维电子气。的温度增加的速率为50℃/秒，直至温度为415℃下达到。样品留在此温度下，持续20秒，然后迅速冷却。取得通过在低欧姆接触电阻最小的持续时间和退火温度的选择的温度。的最佳退火时间可以在基板上的二维电子气的深度取决于。 </li></ol> 3。制备的Ti / Au肖特基信息 该制造步骤的结果， 如图4c所示。 <ol><li>清洁样品在声波浴浸泡在丙酮（2×）和IPA，每次5分钟。与压缩N 2枪吹干。 </li><li>烘烤的样品在烘箱中在125℃下进行15分钟至表面脱水。 </li><li> ，持续90秒，在180℃的热板上在5000rpm，持续30秒，烘烤的附带大衣PMMALMW4％。然后，旋涂聚甲基丙烯酸甲酯高分子量的2％，以5,000 rpm的转速下，持续30秒，烘烤的热板上，在180℃下进行90秒。将所得的抗蚀剂的厚度是〜75纳米〜40纳米，分别。由于将是非常薄的Ti / Au引线，一个单一的聚甲基丙烯酸甲酯层可以使用，但需要进行调整，因而纺丝，曝光和显影参数。这个意见也适用于到t他铝导线和大门（步骤4）。 </li><li> 电子束的过程 ： 该过程的一部分是高度依赖于所用的设备和所需的协议，从而可以从下面描述了一个很大的不同。引线的型态的绘制CAD文件中。在这个文件中，导线必须划为封闭的多边形，宽2微米。的引线所需要的铝门（在步骤4中制备）的键合焊盘（在步骤5中制作）联系。四个对准标记也必须被暴露，以允许垂直，水平，和旋转对应的Al引线和栅极上的Ti / Au肖特基引线。 <ol><li>将样品在扫描电子显微镜（SEM），配备电子束光刻。使用孔径为10μm减小光束的光斑尺寸和设置的加速电压10千伏，先前制造的结构上的对准过程中，以确保良好的对比度。调节聚焦，散光，孔径对应。测量束电流法拉第杯。 </li><li>光束对准​​与先前蚀刻台面和放大倍率设置为300X。 </li><li>公开的线索。的扫描电镜进行编程填充暴露点的数组，以暴露所需的区域。在这些点之间的距离（中心到中心的距离）为5.5 nm和剂量是43μC/ cm 2的（曝光时间将依赖于电子束电流测量步骤3.5.1）。公开对准标记以及允许在步骤4中的钛/金导线与铝门对齐。 </li><li>重复步骤3.5.2和3.5.3的每个的20个样品上的设备。 </li></ol></li><li>将样品浸在IPA开发的抗蚀剂：H 2 O（9:1），持续30秒。该解决方案必须是在温度为20℃。水冲洗30秒，压缩的N 2枪吹干。如果优选的，抗蚀剂的聚甲基丙烯酸甲酯，可开发利用IPA：MIBK溶液，在IPA中漂洗，使反应停止。个不同的D才有发展，将需要时间，如果选择此选项。 </li><li>将等离子灰化样品，将其暴露在O 2等离子体，持续4秒50 W，这消除了5纳米的抵抗，并确保有没有抵制在电子束的过程中形成的沟槽底部留下。 </li><li>将样品浸在溶液中的H 2 SO 4：H 2 O（1:5），持续30秒，并在水冲洗30秒，取出原生氧化层在GaAs。与压缩N 2枪吹干。步骤3.8应尽快进行，以防止重复出现的原生氧化。 </li><li>将样品在电子束蒸发器及存款10纳米钛和20纳米的金，0.1纳米/秒的速度。样本保持器以及接地置于相差至少60厘米，以防止电荷从累积在样品上，在沉积过程中从源，这一点很重要。 </li><li>电梯关闭多余的金属1165卸妆将样品浸在65°C下15分钟。删除任何不需要的金属，可能不会对自己抬起的，用吸管轻轻一喷样品的表面用热卸妆。丙酮和IPA冲洗，每次5分钟。 </li></ol> 4。制作的Al的肖特基信息和盖茨的 该制造步骤的结果， 如图4d所示。 铝的制造肖特基引线和门构成的制造过程中最关键的步骤，因为这些都是定义的点的栅极。重要的是，在电子束聚焦良好的，以及在步骤4.2中调整电子束电流。曝光和显影时间也必须调整，以获得小的，连续的和明确的门。许多协议，这些门并导致钛/金制作，同时暴露在步骤3以前的引线。但是，使用Al的一个优点是，它可以被氧化，theref矿石在允许的元素，如直接沉积到样品表面，而不需要一个大的绝缘层10的最佳栅极。 <ol><li>重复步骤3.1至3.4.2。但是，不要同时使用声波浴清洗样品，以避免损坏的Ti / Au的线索。 </li><li> 电子束处理 ：铝导线和门的图案绘制在一个CAD文件。使用的Al引线接触的Ti / Au的铝门，被绘制为具有宽度为200nm的封闭多边形。然而，铝门不为多边形绘制，但20nm的分离而作为两个单线路。 <ol><li>一旦梁已与台面，放大倍率设置为1500 x对准梁用的Ti / Au肖特基引线。 </li><li>公开的线索。使用剂量为43μC/ cm 2的中心到中心的距离为3.3 nm。 </li><li>公开的大门。请使用0.149 nC的/厘米，中心到中心的距离为1.1 nm的线剂量。这将导致最终的栅极宽度为60nm。 </li><li>重复4.2.1 - 4.2.3步骤，为每个样品20上的设备。 </li></ol></li><li>重复步骤3.5 - 3.7。 </li><li>将样品放入电子束蒸发器及存款30纳米铝在0.3纳米/秒的速度。 </li><li>重复步骤3.10。重要的是非常微妙的，与样品从该步骤起，以避免损坏小的Al栅极。 </li></ol> 5。制作的的肖特基信息和焊盘 该制造步骤的结果示于图4e。 <ol><li>重复步骤2.1 - 2.9，使用光刻掩模的肖特基信息，而不是欧姆焊盘掩膜。 </li><li>将样品放入电子束蒸发器及存款30纳米钛和350 nm的金率0.3纳米/秒，1纳米/秒。金沉积一层厚厚的有利于粘接样品的样品架，因为它是不容易比氏撕裂新新人类层。 </li><li>离地升空的多余的金属和剩余的抗蚀剂在65℃下搅拌3小时，将样品浸在1165移除。删除任何不需要的金属，可能不会对自己抬起的，用吸管轻轻一喷样品的表面用热卸妆。每次5分钟，在丙酮和异丙醇淋洗样品。 </li></ol> 6。切割样品<ol><li>烘烤的样品在烘箱中在125℃下进行15分钟至表面脱水。 </li><li>旋涂S1818，在3,500 rpm的转速下，持续30秒，烘烤的热板上，在115℃下持续1分钟。抗蚀剂层的厚度，这是不重要的，只要它是足够厚，以在切割过程中对样品表面的保护。 </li><li>将切割带的层上的顶面和底面的样品。顶面层胶带切割过程中提供了一层额外的保护设备。 </li><li>将样品放置在切割机中的面朝上。切取试样切割到个人设备所有的方式通过顶层晶圆切割胶带和砷化镓/砷化铝镓没有通过底层切割胶带切割。 </li><li>卸下切割带了几分钟，通过将样品的丙酮溶液的保护抗蚀剂。使用镊子轻轻拉断片切割胶带，自己不要抬。 IPA和冲洗设备，使用N 2枪吹干。 </li></ol>

<ol>
	<li>Shor, P. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polynomial-time+algorithms+for+prime+factorization+and+discrete+logarithms+on+a+quantum+computer.">Polynomial-time algorithms for prime factorization and discrete logarithms on a quantum computer.</a> SIAM J. Sci. Comput. 26 (5), 1484-1509 (1997).</li><li>Bj&#246;rk, M. T., Thelander, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Few-Electron+Quantum+Dots+in+Nanowires.">Few-Electron Quantum Dots in Nanowires.</a> Nano Lett. 4 (9), 1621-1625 (2004).</li><li>Dekker, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Carbon+Nanotubes+as+Molecular+Quantum+Wires.">Carbon Nanotubes as Molecular Quantum Wires.</a> Phys. Today. 52 (5), 22-28 (1999).</li><li>Klein, D. L., McEuen, P. L., Bown Katari, J. E., Roth, R., Alivisatos, A. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+Approach+to+Electrical+Studies+of+Single+Nanocrystals.">An Approach to Electrical Studies of Single Nanocrystals.</a> Appl. Phys. Lett. 68 (18), 2574-2576 (1996).</li><li>Kouwenhoven, L. P., Oosterkamp, T. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Excitation+Spectra+in+Circular+Few-Electron+Quantum+Dots.">Excitation Spectra in Circular Few-Electron Quantum Dots.</a> Science. 278 (5344), 1788-1792 (1997).</li><li>Ciorga, M., Sachrajda, A. S. Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Addition+Spectrum+of+a+Lateral+Dot+from+Coulomb+and+Spin-Blockade+Spectroscopy.">Addition Spectrum of a Lateral Dot from Coulomb and Spin-Blockade Spectroscopy.</a> Phys. Rev. B. 61 (24), R16315-R16318 (2000).</li><li>Baca, A. G., Ashby, C. I. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Fabrication of GaAs Devices. , 350 (2005).</li><li>Barthel, C., Reilly, D. J., Marcus, C. M., Hanson, M. P., Gossard, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+Single-Shot+Measurement+of+a+Singlet-Triplet+Qubit.">Rapid Single-Shot Measurement of a Singlet-Triplet Qubit.</a> Phys. Rev. Lett. 103 (16), 160503 (2009).</li><li>S, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Survey+of+Ohmic+Contacts+to+III-V+Compound+Semiconductors.">A Survey of Ohmic Contacts to III-V Compound Semiconductors.</a> Thin Solid Films. 308, 599-606 (1997).</li><li>Lim, W. H., Huebl, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrostatically+Defined+Few-Electron+Double+Quantum+Dot+in+Silicon.">Electrostatically Defined Few-Electron Double Quantum Dot in Silicon.</a> Appl. Phys. Lett. 94 (17), 173502 (2009).</li><li>Elzerman, J. M., Hanson, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Few-Electron+Quantum+Dot+Circuit+with+Integrated+Charge+Read+Out.">Few-Electron Quantum Dot Circuit with Integrated Charge Read Out.</a> Phys. Rev. B. 67 (16), 161308 (2003).</li><li>Johnson, A. C., Petta, J. R., Marcus, C. M., Hanson, M. P., Gossard, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Singlet-Triplet+Spin+Blockade+and+Charge+Sensing+in+a+Few-Electron+Double+Quantum+Dot.">Singlet-Triplet Spin Blockade and Charge Sensing in a Few-Electron Double Quantum Dot.</a> Phys. Rev. B. 72 (16), 165308 (2005).</li><li>Hanson, R., Kouwenhoven, L. P., Petta, J. R., Tarucha, S., Vandersypen, L. M. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spins+in+Few-Electron+Quantum+Dots.">Spins in Few-Electron Quantum Dots.</a> Rev. Mod. Phys. 79 (4), 1217-1265 (2007).</li><li>Long, A. R., Pioro-Ladri&#232;re, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Origin+of+Switching+Noise+in+GaAs/AlGaAs+Lateral+Gated+Devices.">The Origin of Switching Noise in GaAs/AlGaAs Lateral Gated Devices.</a> Physica E Low Dimens. Syst. Nanostruct. 34 (1-2), 553-556 (2006).</li><li>Koppens, F. H. L., Buizert, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Driven+Coherent+Oscillations+of+a+Single+Electron+Spin+in+a+Quantum+Dot.">Driven Coherent Oscillations of a Single Electron Spin in a Quantum Dot.</a> Nature. 442 (7104), 766-771 (2006).</li><li>Foletti, S., Bluhm, H., Mahalu, D., Umansky, V., Yakobi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Universal+Quantum+Control+of+Two-Electron+Spin+Quantum+Bits+Using+Dynamic+Nuclear+Polarization.">Universal Quantum Control of Two-Electron Spin Quantum Bits Using Dynamic Nuclear Polarization.</a> Nat. Phys. 5 (12), 903-908 (2009).</li><li>Petta, J. R., Lu, H., Gossard, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Coherent+Beam+Splitter+for+Electronic+Spin+States.">A Coherent Beam Splitter for Electronic Spin States.</a> Science. 327 (5966), 669-672 (2010).</li><li>Shulman, M. D., Dial, O. E., Harvey, S. P., Bluhm, H., Umansky, V., Yacoby, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Demonstration+of+Entanglement+of+Electrostatically+Coupled+Singlet-Triplet+Qubits.">Demonstration of Entanglement of Electrostatically Coupled Singlet-Triplet Qubits.</a> Science. 336 (6078), 202-205 (2012).</li><li>Khaetskii, A. V., Loss, D., Glazman, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electron+Spin+Decoherence+in+Quantum+Dots+Due+to+Interaction+with+Nuclei.">Electron Spin Decoherence in Quantum Dots Due to Interaction with Nuclei.</a> Phys. Rev. Lett. 88 (18), 186802 (2002).</li><li>Sakr, M. R., Jiang, H. W., Yablonovitch, E., Croke, E. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fabrication+and+characterization+of+electrostatic+Si/SiGe+Quantum+Dots+with+an+Integrated+Read-Out+Channel.">Fabrication and characterization of electrostatic Si/SiGe Quantum Dots with an Integrated Read-Out Channel.</a> Appl. Phys. Lett. 87 (22), 223104 (2005).</li><li>Liu, X. L., Hug, D., Vandersypen, L. M. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gate-Defined+Graphene+Double+Quantum+Dot+and+Excited+State+Spectroscopy.">Gate-Defined Graphene Double Quantum Dot and Excited State Spectroscopy.</a> Nano Lett. 10 (5), 1623-1627 (2010).</li><li>Frey, T., Leek, P. J., Beck, M., Blais, A., Ihn, T., Ensslin, K., Wallraff, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dipole+Coupling+of+a+Double+Quantum+Dot+to+a+Microwave+Resonator.">Dipole Coupling of a Double Quantum Dot to a Microwave Resonator.</a> Phys. Rev. Lett. 108, 046807 (2012).</li><li>Pioro-Ladri&#232;re, M., Tokyra, Y., Obata, T., Kubo, T., Tarucha, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Micromagnets+for+coherent+control+of+spin-charge+qubit+in+lateral+quantum+dots.">Micromagnets for coherent control of spin-charge qubit in lateral quantum dots.</a> Appl. Phys. Lett. 90 (2), 024105 (2007).</li></ol>

作者什么都没有透露。

上述过程描述一个量子点能够达到几个电子政权的制造协议。然而，给定的参数可能会有所不同，这取决于所使用的设备的型号和校准。因此，剂量暴露于电子束光刻步骤的参数，如将前进行校准的设备的制造。定义其他类型的底物，诸如Si / SiGe的，也提出了2DEG的量子点的方法，可以很容易地适应制造栅极。 对于某些类型的设备，如垂直量子点，该点的源极和漏极的隧道势?...

量子信息科学已经引起了很多的关注，自从它表明，量子算法可以用来解决某些问题成倍的速度比最知名的经典算法1。量子位（量子比特）的一个明显的候选是自旋单电子局限在量子点，因为它是一个两级系统。已经提出了大量的硬件架构的量子点，其中包括半导体纳米线，碳纳米管3，自组装量子点4，半导体的垂直和横向的量子点6为实施。门定义的横向量子点砷化镓/砷化铝镓异质一直非常成功，因为它的多功能性，他们的制造过程是本文的重点。 在横向量子点中的电子约束于样品表面垂直的方向（z方向 ），我小号通过选择适当的基板来实现。该GaAs / AlGaAs多调制掺杂异质结构提出的AlGaAs和GaAs层之间的界面局限于一个二维电子气（2DEG）。这些样品获得低杂质密度调制掺杂技术，结合分子束外延生长，导致2DEG高电子迁移率。的不同层的异质结构，以及它的能带结构的示意图示于图1。高的电子迁移率，需要在二维电子气，以确保在整个表面上的量子点的电子状态的连贯性。为下面描述的制造过程中所用的基材购自加拿大国家研究委员会提出的电子密度为2.2×10 11 cm -2的和电子迁移率为1.69×10 6厘米2 / VSEC。 约束中的电子的方向PARALLEL于样品表面放置在衬底的表面上的金属电极来实现。当这些电极沉积在GaAs样品的表面上，形成肖特基势垒。负电压施加到这些电极导致2DEG仅低于该电子有足够的能量可以穿过的地方障碍。二维电子气的耗损发生时施加的电压足够为负，没有电子有足够的能量，跨越屏障。因此，通过仔细选择电极的几何形状，它是能够捕获样品之间的耗尽区域的一个小数目的电子。上的点和点之间的隧道的能量和样品的其余部分中的二维电子气的电子的数量的控制，可以实现通过微调在电极上的电压。 图2中所示的栅电极和贫电子气的示意图。门结构的设计形成点尖塔巴特尔等人所使用的设计。 为了控制和读出点的电子的数目有关，它是有用的诱导和测量电流通过点。利用量子点接触（QPC），这也需要通过2DEG电流读数也可以做。 2DEG和电压源之间的接触确保了欧姆接触。这些金属焊盘扩散，从样品表面的所有的方式下降到使用一个标准的快速热退火过程7的二维电子气（参见图3a和图4b）。源极和漏极之间的，以避免短路，样品的表面进行蚀刻，因此，二维电子气耗尽后，在某些地区和电流被迫穿越某些特定的信道（参见图3b和图4a）。二维电子气的区域中仍然被称作“台面”。栅极定义的横向量子点上的砷化镓/砷化铝镓基板的整个制造过程中的下面的协议的细节。的方法，是可伸缩的，因为它仍然是一样的，不管正在制造的，如果该设备是单，双或三量子点或量子点的数组。使用这种方法制造的双量子点操纵，测量，结果在进一步的章节讨论。

<table border="1">
		<tbody>
 <tr>
 <td>Name of the reagent/material</td>
 <td>Company</td>
 <td>Product number</td>
 <td>CAS number</td>
 </tr>
 <tr>
 <td>Acetone - CH3COCH3</td>
 <td>Anachemia</td>
 <td>AC-0150</td>
 <td>67-64-1</td>
 </tr>
 <tr>
 <td>Isopropyl Alcohol (IPA) - (CH3)2CHOH</td>
 <td>Anachemia</td>
 <td>AC-7830</td>
 <td>67-63-0</td>
 </tr>
 <tr>
 <td>1165 Remover</td>
 <td>MicroChem Corp</td>
 <td>G050200</td>
 <td>872-50-4</td>
 </tr>
 <tr>
 <td>Microposit MF-319 Developer</td>
 <td>Shipley</td>
 <td>38460</td>
 <td>75-59-2</td>
 </tr>
 <tr>
 <td>Sulfuric Acid - H2SO4</td>
 <td>Anachemia</td>
 <td>AC-8750</td>
 <td>766-93-9</td>
 </tr>
 <tr>
 <td>Hydrogen Peroxide (30%) - H2O2</td>
 <td>Fisher Scientific</td>
 <td></td>
 <td>7722-84-1</td>
 </tr>
 <tr>
 <td>LOR 5A Lift-off resist</td>
 <td>MicroChem Corp</td>
 <td>G516608</td>
 <td>120-92-3</td>
 </tr>
 <tr>
 <td>Microposit S1813 Photo Resist</td>
 <td>Shipley</td>
 <td>41280</td>
 <td>108-65-6</td>
 </tr>
 <tr>
 <td>Microposit S1818 Photo Resist</td>
 <td>Shipley</td>
 <td>41340</td>
 <td>108-65-6</td>
 </tr>
 <tr>
 <td>PMMA LMW 4% in anisole</td>
 <td>MicroChem Corp</td>
 <td></td>
 <td>100-66-3, 9011-14-7</td>
 </tr>
 <tr>
 <td>PMMA HMW 2% in anisole</td>
 <td>MicroChem Corp</td>
 <td></td>
 <td>100-66-3, 9011-14-7</td>
 </tr>
 <tr>
 <td >GaAs/AlGaAs wafer</td>
 <td>National Research Council Canada</td>
 <td>See detailed layer structure in Figure 1.</td>
 <td></td>
 </tr>
 <tr>
 <td>Ni (99.0%)</td>
 <td>Anachemia</td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Ge (99.999%)</td>
 <td>CERAC inc. </td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Au (99.999%)</td>
 <td>Kamis inc. </td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Ti (99.995%)</td>
 <td>Kurt J Lesker</td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Al</td>
 <td>Kamis inc.</td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Silver Epoxy</td>
 <td>Epoxy Technology</td>
 <td>H20E</td>
 <td></td>
 </tr>
	 </tbody>
 </table>

nanofabrication of gate-defined gaas/algaas lateral quantum dots

量子计算机是利用量子效应，如叠加态和纠缠，解决某些问题上最知名的算法成倍的速度比传统计算机的量子位（量子比特）组成的计算机。门定义的横向的GaAs / AlGaAs多量子点是探索实施一个量子比特的众多途径之一。当正确制​​造，这样的设备是能够捕获目标的空间区域中的一个小的电子数。这些电子的自旋态，然后，可以用来实现量子比特的逻辑0和1。鉴于这些量子点的纳米尺度，洁净室设施，提供专门的设备，如扫描电子显微镜和电子束蒸发器需要为他们制造。在整个制造过程中必须小心，夏日的样品表面，以保持清洁，以避免损坏的结构脆弱的栅极。本文栅极定义从晶片的横向量子点的详细的制造协议的工作装置。表征方法和代表性的结果还简要讨论。虽然本文集中在双量子点，单次或三次点，甚至量子点阵列的制作过程中保持不变。此外，该协议可以适应其它底材，诸如Si / SiGe半导体制造横向的量子点。

在上述处理中的关键步骤之一是在台面蚀刻（步骤1）。这是重要的，同时避免过刻蚀，刻蚀到足以去除的2DEG如下。因此，建议使用GaAs体材料样品模型测试前的蚀刻液进行蚀刻的砷化镓/砷化铝镓样品。的砷化镓/砷化铝镓异质结构的刻蚀速率比GaAs的大，但虚拟对象的蚀刻可以给出指示是否比平常更多或更少的反应溶液和实际样品的蚀刻时间可作相应调整。 一旦设备已被制造?...

Watch this Scientific Journal Video about Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots at JoVE.com

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots

本文提出了一个详细的制作门定义的半导体横向量子点砷化镓异质协议。这些纳米器件被用来捕获一些电子作为量子比特的量子信息处理或其他细观实验，如相干电导测量使用。

纳米加工门定义的GaAs / AlGaAs多量子点横向

A quantum computer is a computer composed of quantum bits (qubits) that takes advantage of quantum effects, such as superposition of states and ...

nanofabrication-of-gate-defined-gaasalgaas-lateral-quantum-dots

Research

JoVE Journal

Engineering

16.0K 次观看.  Université de Sherbrooke. 本文提出了一个详细的制作门定义的半导体横向量子点砷化镓异质协议。这些纳米器件被用来捕获一些电子作为量子比特的量子信息处理或其他细观实验，如相干电导测量使用。

视频: Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots

Compact Quantum Dots for Single-molecule Imaging

Single-molecule imaging is an important tool for understanding the mechanisms of biomolecular function and for visualizing the spatial and temporal heterogeneity of molecular behaviors that underlie cellular biology 1-4. To image an individual molecule of interest, it is typically conjugated to a fluorescent tag (dye, protein, bead, or quantum dot) and observed with epifluorescence or total internal reflection fluorescence (TIRF) microscopy. While dyes and fluorescent proteins have been the mainstay of fluorescence imaging for decades, their fluorescence is unstable under high photon fluxes necessary to observe individual molecules, yielding only a few seconds of observation before complete loss of signal. Latex beads and dye-labeled beads provide improved signal stability but at the expense of drastically larger hydrodynamic size, which can deleteriously alter the diffusion and behavior of the molecule under study.
Quantum dots (QDs) offer a balance between these two problematic regimes. These nanoparticles are composed of semiconductor materials and can be engineered with a hydrodynamically compact size with exceptional resistance to photodegradation 5. Thus in recent years QDs have been instrumental in enabling long-term observation of complex macromolecular behavior on the single molecule level. However these particles have still been found to exhibit impaired diffusion in crowded molecular environments such as the cellular cytoplasm and the neuronal synaptic cleft, where their sizes are still too large 4,6,7.
Recently we have engineered the cores and surface coatings of QDs for minimized hydrodynamic size, while balancing offsets to colloidal stability, photostability, brightness, and nonspecific binding that have hindered the utility of compact QDs in the past 8,9. The goal of this article is to demonstrate the synthesis, modification, and characterization of these optimized nanocrystals, composed of an alloyed HgxCd1-xSe core coated with an insulating CdyZn1-yS shell, further coated with a multidentate polymer ligand modified with short polyethylene glycol (PEG) chains (Figure 1). Compared with conventional CdSe nanocrystals, HgxCd1-xSe alloys offer greater quantum yields of fluorescence, fluorescence at red and near-infrared wavelengths for enhanced signal-to-noise in cells, and excitation at non-cytotoxic visible wavelengths. Multidentate polymer coatings bind to the nanocrystal surface in a closed and flat conformation to minimize hydrodynamic size, and PEG neutralizes the surface charge to minimize nonspecific binding to cells and biomolecules. The end result is a brightly fluorescent nanocrystal with emission between 550-800 nm and a total hydrodynamic size near 12 nm. This is in the same size range as many soluble globular proteins in cells, and substantially smaller than conventional PEGylated QDs (25-35 nm).

We describe the preparation of colloidal quantum dots with minimized hydrodynamic size for single-molecule fluorescence imaging. Compared to conventional quantum dots, these nanoparticles are similar in size to globular proteins and are optimized for single-molecule brightness, stability against photodegradation, and resistance to nonspecific binding to proteins and cells.

紧凑型量子点的单分子成像

Single-molecule imaging is an important tool for  understanding the mechanisms of biomolecular function and for visualizing the  spatial and temporal ...

科研

工程学

Gradient Echo Quantum Memory in Warm Atomic Vapor

Gradient echo memory (GEM) is a protocol for storing optical quantum states of light in atomic ensembles. The primary motivation for such a technology is that quantum key distribution (QKD), which uses Heisenberg uncertainty to guarantee security of cryptographic keys, is limited in transmission distance. The development of a quantum repeater is a possible path to extend QKD range, but a repeater will need a quantum memory. In our experiments we use a gas of rubidium 87 vapor that is contained in a warm gas cell. This makes the scheme particularly simple. It is also a highly versatile scheme that enables in-memory refinement of the stored state, such as frequency shifting and bandwidth manipulation. The basis of the GEM protocol is to absorb the light into an ensemble of atoms that has been prepared in a magnetic field gradient. The reversal of this gradient leads to rephasing of the atomic polarization and thus recall of the stored optical state. We will outline how we prepare the atoms and this gradient and also describe some of the pitfalls that need to be avoided, in particular four-wave mixing, which can give rise to optical gain.

The gradient echo memory is a protocol for storing optical quantum states of light in atomic ensembles. Quantum memory is a key element of a quantum repeater, which can extend the range of quantum key distribution. We outline the operation of the scheme when implemented in a 3-level atomic ensemble.

梯度回波量子存储在温暖的原子蒸气

Gradient  echo memory (GEM) is a protocol for storing optical quantum states of light in  atomic ensembles. The primary motivation for such a technology ...

Analysis of Contact Interfaces for Single GaN Nanowire Devices

Single GaN nanowire (NW) devices fabricated on SiO2 can exhibit a strong degradation after annealing due to the occurrence of void formation at the contact/SiO2 interface. This void formation can cause cracking and delamination of the metal film, which can increase the resistance or lead to a complete failure of the NW device. In order to address issues associated with void formation, a technique was developed that removes Ni/Au contact metal films from the substrates to allow for the examination and characterization of the contact/substrate and contact/NW interfaces of single GaN NW devices. This procedure determines the degree of adhesion of the contact films to the substrate and NWs and allows for the characterization of the morphology and composition of the contact interface with the substrate and nanowires. This technique is also useful for assessing the amount of residual contamination that remains from the NW suspension and from photolithographic processes on the NW-SiO2 surface prior to metal deposition. The detailed steps of this procedure are presented for the removal of annealed Ni/Au contacts to Mg-doped GaN NWs on a SiO2 substrate.

A technique was developed that removes Ni/Au contact metal films from their substrate to allow for the examination and characterization of the contact/substrate and contact/NW interfaces of single GaN nanowire devices.

单氮化镓纳米线设备分析接触界面

Single GaN nanowire (NW) devices fabricated on SiO2 can exhibit  a strong degradation after annealing due to the  occurrence of void formation at the ...

Construction and Characterization of External Cavity Diode Lasers for Atomic Physics

Since their development in the late 1980s, cheap, reliable external cavity diode lasers (ECDLs) have replaced complex and expensive traditional dye and Titanium Sapphire lasers as the workhorse laser of atomic physics labs1,2. Their versatility and prolific use throughout atomic physics in applications such as absorption spectroscopy and laser cooling1,2 makes it imperative for incoming students to gain a firm practical understanding of these lasers. This publication builds upon the seminal work by Wieman3, updating components, and providing a video tutorial. The setup, frequency locking and performance characterization of an ECDL will be described. Discussion of component selection and proper mounting of both diodes and gratings, the factors affecting mode selection within the cavity, proper alignment for optimal external feedback, optics setup for coarse and fine frequency sensitive measurements, a brief overview of laser locking techniques, and laser linewidth measurements are included.

This is an instructional paper to guide the construction and diagnostics of external cavity diode lasers (ECDLs), including component selection and optical alignment, as well as the basics of frequency reference spectroscopy and laser linewidth measurements for applications in the field of atomic physics.

外腔半导体激光器的原子物理的构建与鉴定

Since their development in the late 1980s, cheap, reliable external cavity diode lasers (ECDLs) have replaced complex and expensive traditional dye and ...

Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators

Engineering non-classical states of the electromagnetic field is a central quest for quantum optics1,2. Beyond their fundamental significance, such states are indeed the resources for implementing various protocols, ranging from enhanced metrology to quantum communication and computing. A variety of devices can be used to generate non-classical states, such as single emitters, light-matter interfaces or non-linear systems3. We focus here on the use of a continuous-wave optical parametric oscillator3,4. This system is based on a non-linear &#967;2 crystal inserted inside an optical cavity and it is now well-known as a very efficient source of non-classical light, such as single-mode or two-mode squeezed vacuum depending on the crystal phase matching. 
Squeezed vacuum is a Gaussian state as its quadrature distributions follow a Gaussian statistics. However, it has been shown that number of protocols require non-Gaussian states5. Generating directly such states is a difficult task and would require strong &#967;3 non-linearities. Another procedure, probabilistic but heralded, consists in using a measurement-induced non-linearity via a conditional preparation technique operated on Gaussian states. Here, we detail this generation protocol for two non-Gaussian states, the single-photon state and a superposition of coherent states, using two differently phase-matched parametric oscillators as primary resources. This technique enables achievement of a high fidelity with the targeted state and generation of the state in a well-controlled spatiotemporal mode.

We describe the reliable generation of non-Gaussian states of traveling optical fields, including single-photon states and coherent state superpositions, using a conditional preparation method operated on the non-classical light emitted by optical parametric oscillators. Type-I and type-II phase-matched oscillators are considered and common procedures, such as the required frequency filtering or the high-efficiency quantum state characterization by homodyning, are detailed.

光与连续波光学参量振荡器的量子态工程

Engineering non-classical states of the electromagnetic field is a central quest for quantum optics1,2. Beyond their fundamental significance, such states ...

Selective Area Modification of Silicon Surface Wettability by Pulsed UV Laser Irradiation in Liquid Environment

The wettability of silicon (Si) is one of the important parameters in the technology of surface functionalization of this material and fabrication of biosensing devices. We report on a protocol of using KrF and ArF lasers irradiating Si (001) samples immersed in a liquid environment with low number of pulses and operating at moderately low pulse fluences to induce Si wettability modification. Wafers immersed for up to 4 hr in a 0.01% H2O2/H2O solution did not show measurable change in their initial contact angle (CA) ~75&#176;. However, the 500-pulse KrF and ArF lasers irradiation of such wafers in a microchamber filled with 0.01% H2O2/H2O solution at 250 and 65 mJ/cm2, respectively, has decreased the CA to near 15&#176;, indicating the formation of a superhydrophilic surface. The formation of OH-terminated Si (001), with no measurable change of the wafer&#8217;s surface morphology, has been confirmed by X-ray photoelectron spectroscopy and atomic force microscopy measurements. The selective area irradiated samples were then immersed in a biotin-conjugated fluorescein-stained nanospheres solution for 2 hr, resulting in a successful immobilization of the nanospheres in the non-irradiated area. This illustrates the potential of&#160;the method for selective area biofunctionalization and fabrication of advanced Si-based biosensing architectures. We also describe a similar protocol of irradiation of wafers immersed in methanol (CH3OH) using ArF laser operating at pulse fluence of 65 mJ/cm2 and in situ formation of a strongly hydrophobic surface of Si (001) with the CA of 103&#176;. The XPS results indicate ArF laser induced formation of Si&#8211;(OCH3)x compounds responsible for the observed hydrophobicity. However, no such compounds were found by XPS on the Si surface irradiated by KrF laser in methanol, demonstrating the inability of the KrF laser to photodissociate methanol and create -OCH3 radicals.

We report on a process of in situ alteration of HF treated Si (001) surface into a hydrophilic or hydrophobic state by irradiating samples in microfluidic chambers filled with&#160;H2O2/H2O solution (0.01%-0.5%) or methanol solutions using pulsed UV laser of a relative low pulse fluence.

硅表面润湿性的选择区域改性脉冲紫外激光照射在液体环境

The wettability of silicon (Si) is one of the important parameters in the technology of surface functionalization of this material and fabrication of ...

Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping

As mass-produced silicon transistors have reached the nano-scale, their behavior and performances are increasingly affected, and often deteriorated, by quantum mechanical effects such as tunneling through single dopants, scattering via interface defects, and discrete trap charge states. However, progress in silicon technology has shown that these phenomena can be harnessed and exploited for a new class of quantum-based electronics. Among others, multi-layer-gated silicon metal-oxide-semiconductor (MOS) technology can be used to control single charge or spin confined in electrostatically-defined quantum dots (QD). These QD-based devices are an excellent platform for quantum computing applications and, recently, it has been demonstrated that they can also be used as single-electron pumps, which are accurate sources of quantized current for metrological purposes. Here, we discuss in detail the fabrication protocol for silicon MOS QDs which is relevant to both quantum computing and quantum metrology applications. Moreover, we describe characterization methods to test the integrity of the devices after fabrication. Finally, we give a brief description of the measurement set-up used for charge pumping experiments and show representative results of electric current quantization.

The fabrication process and experimental characterization techniques relevant to single-electron pumps based on silicon metal-oxide-semiconductor quantum dots are discussed.

硅金属 - 氧化物 - 半导体量子点单电子泵

As mass-produced silicon transistors have reached the nano-scale, their behavior and performances are increasingly affected, and often deteriorated, by ...

Measurement of Quantum Interference in a Silicon Ring Resonator Photon Source

Silicon photonic chips have the potential to realize complex integrated quantum information processing circuits, including photon sources, qubit manipulation, and integrated single-photon detectors. Here, we present the key aspects of preparing and testing a silicon photonic quantum chip with an integrated photon source and two-photon interferometer. The most important aspect of an integrated quantum circuit is minimizing loss so that all of the generated photons are detected with the highest possible fidelity. Here, we describe how to perform low-loss edge coupling by using an ultra-high numerical aperture fiber to closely match the mode of the silicon waveguides. By using an optimized fusion splicing recipe, the UHNA fiber is seamlessly interfaced with a standard single-mode fiber. This low-loss coupling allows the measurement of high-fidelity photon production in an integrated silicon ring resonator and the subsequent two-photon interference of the produced photons in a closely integrated Mach-Zehnder interferometer. This paper describes the essential procedures for the preparation and characterization of high-performance and scalable silicon quantum photonic circuits.

Silicon photonic chips have the potential to realize complex integrated quantum systems. Presented here is a method for preparing and testing a silicon photonic chip for quantum measurements.

量子干涉效应在硅谐振环光子源测量

Silicon photonic chips have the potential to realize complex integrated quantum information processing circuits, including photon sources, qubit ...

Experimental Methods for Trapping Ions Using Microfabricated Surface Ion Traps

Ions trapped in a quadrupole Paul trap have been considered one of the strong physical candidates to implement quantum information processing. This is due to their long coherence time and their capability to manipulate and detect individual quantum bits (qubits). In more recent years, microfabricated surface ion traps have received more attention for large-scale integrated qubit platforms. This paper presents a microfabrication methodology for ion traps using micro-electro-mechanical system (MEMS) technology, including the fabrication method for a 14 &#181;m-thick dielectric layer and metal overhang structures atop the dielectric layer. In addition, an experimental procedure for trapping ytterbium (Yb) ions of isotope 174 (174Yb+) using 369.5 nm, 399 nm, and 935 nm diode lasers is described. These methodologies and procedures involve many scientific and engineering disciplines, and this paper first presents the detailed experimental procedures. The methods discussed in this paper can easily be extended to the trapping of Yb ions of isotope 171 (171Yb+) and to the manipulation of qubits.

This paper presents a microfabrication methodology for surface ion traps, as well as a detailed experimental procedure for trapping ytterbium ions in a room-temperature environment.

利用 Microfabricated 表面离子阱捕获离子的实验方法

Ions trapped in a quadrupole Paul trap have been considered one of the strong physical candidates to implement quantum information processing. This is due ...

Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection

The ability to perform simultaneous resonant excitation and fluorescence detection is important for quantum optical measurements of quantum dots (QDs). Resonant excitation without fluorescence detection &#8211; for example, a differential transmission measurement &#8211; can determine some properties of the emitting system, but does not allow applications or measurements based on the emitted photons. For example, the measurement of photon correlations, observation of the Mollow triplet, and realization of single photon sources all require collection of the fluorescence. Incoherent excitation with fluorescence detection &#8211; for example, above band-gap excitation &#8211; can be used to create single photon sources, but the disturbance of the environment due to the excitation reduces the indistinguishability of the photons. Single photon sources based on QDs will have to be resonantly excited to have high photon indistinguishability, and simultaneous collection of the photons will be necessary to make use of them. We demonstrate a method to resonantly excite a single QD embedded in a planar cavity by coupling the excitation beam into this cavity from the cleaved face of the sample while collecting the fluorescence along the sample&#39;s surface normal direction. By carefully matching the excitation beam to the waveguide mode of the cavity, the excitation light can couple into the cavity and interact with the QD. The scattered photons can couple to the Fabry-Perot mode of the cavity and escape in the surface normal direction. This method allows complete freedom in the detection polarization, but the excitation polarization is restricted by the propagation direction of the excitation beam. The fluorescence from the wetting layer provides a guide to align the collection path with respect to the excitation beam. The orthogonality of the excitation and detection modes enables resonant excitation of a single QD with negligible laser scattering background.

Resonant excitation of a single self-assembled quantum dot can be achieved using an excitation mode orthogonal to the fluorescence collection mode. We demonstrate a method using the waveguide and Fabry-Perot modes of a planar microcavity surrounding the quantum dots. The method allows complete freedom in the detection polarization.

用正交激励和检测方法研究平面腔内铟量子点的共振荧光

The ability to perform simultaneous resonant excitation and fluorescence detection is important for quantum optical measurements of quantum dots (QDs). ...