这项工作是由ERA-NET CHIST-ERA（&#39;量化尺度“项目），并在ERC开始授予&#39;HybridNet&#39;的支持。 F.巴博萨承认从中国北车和FAPESP，和K黄从中国基金会的全国优秀博士学位论文（PY2012004）的作者和中国国家留学基金委的支持的支持。 C.法布尔和J. Laurat是区大学研究所法兰西的成员。

1，光学参量振荡器<ol><li>建立一个4厘米长semimonolithic线性腔（改进的机械稳定性，减少腔内损耗）。输入镜直接涂布在一个面的非线性晶体。 </li><li>选择95％的输入耦合器反射的泵以532纳米和​​高反射为在1064纳米的信号光和闲频光。相反地​​，选择输出耦合器是高反射性的泵和透过率T = 10％的红外线。该OPO的自由光谱范围等于Δω= 4.3 GHz和带宽大约为60兆赫。使空腔三重共振， 即用于泵和用于下变频的字段。 </li><li>使用KTP晶体的II型OPO系统或PPKTP晶体的I型光参量振荡器。温度稳定的晶体在它们的相位匹配温度。 </li><li>使用作为激光源的连续波倍频Nd：YAG激光器。泵的OPO在532 nm和使用中当红外光，空间滤波由高精细度的空腔（模式清洁器），作为本地振荡器（LO）的零差检波后。 </li><li>实现所述泵和所述腔模式之间的模式匹配。 </li><li>由磅 - 德雷弗霍尔技术锁定在泵共振腔的长度。为了这个目的，应用12MHz的电光调制到泵和检测的光回射从同一个光隔离器的空腔中。 </li></ol> 2条件准备：过滤的预示路径<ol><li> OPO的输出分成两种模式。一个对应于所述前驱模式，而另一种是将由零差检测来检测出的预示状态。 </li><li>引导朝向单光子探测器的前驱模式。具体地，对于II型OPO，由偏振光分束器（PBS）中分离的正交信号和闲散的模式。对于I型OPO，挖掘出了压缩真空的一小部分（3％）分束器（BS）。 </li><li>过滤前驱模式，以消除由于OPO腔的频率非简并模式。对于一个OPO，输出的确包含许多成对相关，但频谱分离模式下，ω0 +Nδω和ω0-ωNδ其中n是一个整数。以产生预示的状态在载频，它是必要的，以过滤掉所有这些非简并模式。 <ol><li>先用一个干涉滤波器与0.5纳米的带宽。 </li><li>添加一个自制的线性法布里 - 珀罗腔与自由光谱范围为330千兆赫和300兆赫（约0.4毫米，手腕大约1000的长度）的带宽。空腔的带宽被选择为比OPO和自由光谱范围为比干涉滤波器的频率窗口较大的一方大。 </li><li>实现至少一个整体25分贝排斥非简并模式。 </li></ol></li><li>锁定过滤法布里 -珀罗腔由抖动和锁定技术。 <ol><li>为了这个目的，通过一个光开关注入一个反方向传播辅助光束，并且在过滤腔由一个光隔离器的入口处拒绝它。检测到的光输出。 </li><li>在10毫秒锁定腔和90毫秒与辅助光束折测量周期之后启动。 </li></ol></li><li>在测量期间通过一个单光子检测器检测经滤波的前驱模式。超导单光子探测器（SSPD）是用来限制暗噪声量（几赫兹），否则将降低的条件状态的保真度。 </li></ol> 3，量子态层析成像由零差检测<ol><li>检测所述预示着状态与平衡零差检测的50/50分束器，其中该字段来表征和强烈的连续波本地振荡器（LO，6毫瓦）的组成被带到干扰，并且对高量子EFF的iciency的InGaAs光电二极管。 </li><li>为了对齐检测，注入OPO腔明亮的辅助光束在1,064 nm和模式匹配此模式与LO模式。实现了条纹可见度接近于1。任何模式不匹配二次转化为检测的损失。 </li><li>检查零差检测性能。随着6毫瓦的LO功率，散粒噪声极限（SNL）是平高达50 MHz。它是电子噪音低分析主频（MHz），高于16 dB在50 MHz的分析频率高于20 dB以上。这个距离是一个非常重要的参数，因为它转化为在检测的损失（10分贝（20分贝）的距离转换成一个10％（1％）的有效损失）24。 </li><li>用于从单光子检测器检测每个事件，与5 GS /秒的期间100纳秒的采样速率示波器记录的零拍光电流​​。在测量过程中扫描的LO相位用的PZT安装镜子。 </li><li>每个过滤段记录了GI法师时间模式函数来获取每个成功制备条件状态的单个积分值。的最优模式功能的低增益接近于一个双面指数函数25与衰减常数等于OPO带宽的倒数。的最优模式也可以通过使用特征展开的自相关函数26的发现。 </li><li>累积的测量（50000顷所需的断层扫描）和后处理的数据，最大似然算法27。此过程使重建预示着状态的密度矩阵和相应的维格 ​​纳函数8。 </li></ol> 4，有条件的制备单光子态的具有II型OPO <ol><li>泵的II型OPO远低于阈值（1毫瓦这里进行了80毫瓦阈值）有一个非常低的多光子对的概率。 </li></ol>相干的5。准备条件态叠加与I型OPO <ol><li>检查该OPO接近临界值用频谱分析仪所产生的压缩真空。所测量的噪声谱示于图3。 </li><li>操作OPO的泵浦功率，能够观察挤在低边带频率（几兆赫）的约3分贝。 </li><li>在零差测量，相位信息是用于相位依赖状态，例如CSS的状态非常重要。扫描LO相位具有10赫兹的锯齿波具有90％的占空比（对应于90毫秒的测量周期和10毫秒的锁定期。）同步扫描，以确保在测量期间，有一个单一的的PZT安装反射镜的一个方向扫描。 </li><li>使用零差信号来测量的方差，然后推断测定正交的相位。 </li></ol>

<ol>
	<li>Dell'Anno, F., 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=Multiphoton+quantum+optics+and+quantum+state+engineering.">Multiphoton quantum optics and quantum state engineering.</a> Phys. Reports. 428, 53-168 (2006).</li><li>O'Brien, J. L., 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=Photonic+quantum+technologies.">Photonic quantum technologies.</a> Nature Photon. 3, 687-695 (2009).</li><li>Bachor, H. -. A., Ralph, T. 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> A guide to experiments in quantum optics. , (2004).</li><li>Reid, M. D., 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+Einstein-Podolsky-Rosen+paradox:+from+concepts+to+applications.">The Einstein-Podolsky-Rosen paradox: from concepts to applications.</a> Rev. Mod. Phys. 81, 1727-1751 (2009).</li><li>Van Loock, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optical+hybrid+approaches+to+quantum+information.">Optical hybrid approaches to quantum information.</a> Laser &amp; Photonics Review. 5, 167-200 (2011).</li><li>Knill, E., 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=A+scheme+for+efficient+quantum+computation+with+linear+optics.">A scheme for efficient quantum computation with linear optics.</a> Nature. 409, 46-52 (2001).</li><li>Ralph, T. 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=Quantum+computation+with+optical+coherent+states.">Quantum computation with optical coherent states.</a> Phys. Rev. A. 68, 042319 (2003).</li><li>Leonhardt, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Measuring the quantum state of light. , (1997).</li><li>Hong, C. K., Mandel, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+realization+of+a+localized+one-photon+state.">Experimental realization of a localized one-photon state.</a> Phys. Rev. Lett. 56, 58-60 (1986).</li><li>Lvovsky, A. I., 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=Quantum+state+reconstruction+of+the+single-photon+Fock+state.">Quantum state reconstruction of the single-photon Fock state.</a> Phys. Rev. Lett. 87, (2001).</li><li>Ourjoumtsev, A., 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=Generating+optical+Schr&#246;dinger+kittens+for+quantum+information+processing.">Generating optical Schr&#246;dinger kittens for quantum information processing.</a> Science. 312, 83-86 (2006).</li><li>D'Auria, V., 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=Effect+of+the+heralding+detector+properties+on+the+conditional+generation+of+single-photon+states.">Effect of the heralding detector properties on the conditional generation of single-photon states.</a> Eur. Phys. Journ. D. 66, 249 (2012).</li><li>D'Auria, V., 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=Quantum+decoherence+of+single-photon+counters.">Quantum decoherence of single-photon counters.</a> Phys. Rev. Lett. 107, (2011).</li><li>Huisman, S. 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=Instant+single-photon+Fock+state+tomography.">Instant single-photon Fock state tomography.</a> Opt. Lett. 34, 2739-2741 (2009).</li><li>Morin, O., 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=High-fidelity+single-photon+source+based+on+a+Type+II+optical+parametric+oscillator.">High-fidelity single-photon source based on a Type II optical parametric oscillator.</a> Opt. Lett. 37, 3738-3740 (2012).</li><li>Ou, Z. Y., 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=Realization+of+the+Einstein-Podolski-Rosen+paradox+for+continuous+variables.">Realization of the Einstein-Podolski-Rosen paradox for continuous variables.</a> Phys. Rev. Lett. 68, 3663-3666 (1992).</li><li>Laurat, J., 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=.">.</a> Type-II Optical Parametric Oscillator: a versatile source of quantum correlations and entanglement in Quantum information with continuous-variables of atoms and light. , (2005).</li><li>Laurat, J., 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=Compact+source+of+Einstein-Podolski-Rosen+entanglement+and+squeezing+at+very+low+noise+frequencies.">Compact source of Einstein-Podolski-Rosen entanglement and squeezing at very low noise frequencies.</a> Phys. Rev. A. 70, (2004).</li><li>D'Auria, V., 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=Full+characterization+of+Gaussian+bipartite+entangled+states+by+a+single+homodyne+detector.">Full characterization of Gaussian bipartite entangled states by a single homodyne detector.</a> Phys. Rev. Lett. 102, (2009).</li><li>Dakna, 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=Generating+Schr&#246;dinger-cat-like+states+by+means+of+conditional+measurements+on+a+beam+splitter.">Generating Schr&#246;dinger-cat-like states by means of conditional measurements on a beam splitter.</a> Phys. Rev. A. 55, 3184-3194 (1997).</li><li>Gerrits, T., 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=Generation+of+optical+coherent-state+superpositions+by+number-resolved+photon+subtraction+from+the+squeezed+vacuum.">Generation of optical coherent-state superpositions by number-resolved photon subtraction from the squeezed vacuum.</a> Phys. Rev. A. 82, (2010).</li><li>Neergaard-Nielsen, J. S., 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=Generation+of+a+Superposition+of+Odd+Photon+Number+States+for+Quantum+Information+Networks.">Generation of a Superposition of Odd Photon Number States for Quantum Information Networks.</a> Phys. Rev. Lett. 97, (2006).</li><li>Wakui, K., 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=Photon+subtracted+squeezed+states+generated+with+periodically+poled+KTiOPO4.">Photon subtracted squeezed states generated with periodically poled KTiOPO4.</a> Opt. Express. 15, 3568-3574 (2007).</li><li>Kumar, 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=Versatile+wideband+balanced+detector+for+quantum+optical+homodyne+tomography.">Versatile wideband balanced detector for quantum optical homodyne tomography.</a> Optics Com. 285, 5259-5267 (2012).</li><li>Nielsen, A. E. B., M&#248;lmer, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Single-photon-state+generation+from+a+continuous-wave+nondegenerate+optical+parametric+oscillator.">Single-photon-state generation from a continuous-wave nondegenerate optical parametric oscillator.</a> Phys. Rev. A. 75, (2007).</li><li>Morin, O., 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=Experimentally+accessing+the+optimal+temporal+mode+of+traveling+quantum+light+states.">Experimentally accessing the optimal temporal mode of traveling quantum light states.</a> Phys. Rev. Lett. 111, 213-602 (2013).</li><li>Lvovsky, A. I., Raymer, M. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Continuous-variable+optical+quantum-state+tomography.">Continuous-variable optical quantum-state tomography.</a> Rev. Mod. Phys. 81, 299-332 (2009).</li><li>Marek, P., Fiurasek, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Elementary+gates+for+quantum+information+with+superposed+coherent+states.">Elementary gates for quantum information with superposed coherent states.</a> Phys. Rev. A. 82, (2010).</li><li>Morin, O., 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=Remote+creation+of+hybrid+entanglement+between+particle-like+and+wave-like+optical+qubits.">Remote creation of hybrid entanglement between particle-like and wave-like optical qubits.</a> Nat. Photonics. Eprint. , (2013).</li></ol>

作者宣称，他们有没有竞争的财务权益。

这里提出的条件制备技术总是在初始偶资源和由前驱检测器进行测量之间的相互影响。这两种成分强烈影响所产生的状态的量子特性。 首先，将制备的状态的纯度在很大程度上依赖于初始资源中的一个，因此，一个&#39;好&#39;OPO是必需的。什么是“好”的OPO？它的量，逃生效率η接近一致的装置。参数η是由输出耦合器，T的传动比，并且该传输和腔内损耗（从散射或吸收在晶?...

工程师行驶光场量子态的能力对于量子信息科学与技术1，包括量子通信，计算和测量中央的要求。在这里，我们讨论使用作为主要资源由低于阈值操作的连续波光学参量振荡器3,4发出的光的一些特定量子态的制备和表征。具体来说，两个系统将被视为-一个II型相位匹配光参量振荡器和一个I型OPO -分别实现了可靠的新一代的预报单光子和光学相干态叠加（CSS）的形式，即状态|α &gt; - | - α&gt;。这些国家是为各种量子信息协议的实现的重要资源，从线性光学量子计算6光混合协议5,7。显著的处理P<html>这里反感允许获得真空和发射的低混合成良好控制的时空模式。 一般来说，量子态可以根据在相空间中的准概率分布称为Wigner函数W（X，P）8的形状被分类为高斯状态和非高斯状态。对于非高斯状态，维格纳函数可以取负值，非古典的强烈签名。单光子或相干态的叠加态的确非高斯状态。 一种有效的方法，用于产生这样的状态被称为条件制备工艺，其中初始高斯资源是结合了所谓的非高斯测量诸如光子计数9,10,11,12,13。这个总体方案，概率，但预示着，被描绘在图1a。 “FO：内容宽度=”5英寸“FO：SRC =”/ files/ftp_upload/51224/51224fig1highres.jpg“SRC =”/ files/ftp_upload/51224/51224fig1.jpg“/&gt; 图1（a）批准，制备技术的概念方案。 （b）由正交极化光子对（II型OPO）条件制备单光子态分离偏振分束器。（三）有条件通过从压缩真空态减去一个单光子相干态叠加的准备（I型OPO）。 通过测量一个二分纠缠态的一种模式，其他模式被投射到一个状态，这将依赖于这种测量和初始纠缠资源12,13。 什么是需要的，以产生上述的状态所需要的资源和前驱探测器？单光子态可以使用双光束来产生， 即光子数相关联的光束。单p的检测豪腾在一个模式然后预示着在其他模式9,10,14,15的单光子的产生。一个频率简并II型OPO 16,17,18,19的确是一个非常适合源出于此目的。信号和闲散的光子光子数相关，与正交极化发射。检测在一个偏振模式的单光子突出的另一个成单个光子状态， 如图1b所示 。 关于相干态的叠加态，他们可以从获得的压缩真空态20无论是脉冲单通参量下转换11,21或由I型OPO 22,23减去一个单光子产生。减法是通过攻丝的光的一小部分上的分束器和检测单个光子在这种模式下（ 图1c）上进行。压缩真空甚至光子数态的叠加，从而减去一个单光子商机以奇光子数态，因而具有较高的保真度等于和小幅度的两个相干态的线性叠加的叠加。出于这个原因，名称为“薛定谔小猫&#39;有时被赋予这种状态。 用于产生这些状态的一般方法是这样相似，但不同的一次光源。的前驱路径和检测技术过滤是什么OPO的类型所使用的相同。本系列协议的细节如何从连续波光学参量振荡器生成这两个非高斯状态以及如何将它们以高效率的特点。

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			<td height="21" style="height:21px;width:216px;">Pump laser</td>
			<td style="width:71px;">Innolight</td>
			<td style="width:119px;">Diabolo</td>
			<td style="width:217px;">Dual output, IR and 532 nm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">KTP and PPKTP crystal</td>
			<td style="width:71px;">Raicol</td>
			<td style="width:119px;"></td>
			<td>Available from other vendors</td>
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		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Interferential filters</td>
			<td style="width:71px;">Barr associates</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">High efficiency photodiodes</td>
			<td style="width:71px;">Fermionics</td>
			<td style="width:119px;"></td>
			<td>Quantum efficiency above 97%</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Oscilloscope&#160;</td>
			<td style="width:71px;">Lecroy</td>
			<td style="width:119px;">Wave runner 610 Zi</td>
			<td>Used for data acquisition</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Spectrum analyser</td>
			<td style="width:71px;">Agilent</td>
			<td style="width:119px;">N9000A</td>
			<td>Available from other vendors</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Faraday rotator</td>
			<td style="width:71px;">Qioptic</td>
			<td style="width:119px;">FR-1060-5SC</td>
			<td>Available from other vendors</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">PZT</td>
			<td style="width:71px;">PI</td>
			<td style="width:119px;">P-016.00H</td>
			<td>Available from other vendors</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Superconducting single-photon detectors</td>
			<td style="width:71px;">Scontel</td>
			<td style="width:119px;">SSPD</td>
			<td>low dark counts</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Optical switch</td>
			<td style="width:71px;">Thorlabs</td>
			<td style="width:119px;">OSW12-980E</td>
			<td>Available from other vendors</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;"></td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

quantum state engineering of light with continuous-wave optical parametric oscillators

工程电磁场的非经典态是一个中央寻求量子光学1,2。超出了他们的根本意义，这样的状态确实实现各种协议，从加强计量量子通信和计算资源。各种装置可被用来产生非经典状态，如单发射器，光与物质的界面或非线性系统3。我们在这里集中使用连续波光学参量振荡器3,4的。这个系统是基于非线性χ2晶体的光学腔内插入，并且它现在众所周知，作为非经典光，如单模或多取决于晶体双模压缩真空一种非常有效的源相位匹配。 压缩真空是一个高斯状态为正交分布遵循高斯统计。然而，已经表明，一些协议需要非高斯西安国5。直接产生这样的状态是一个艰巨的任务，需要强大的χ3非线性。另一个程序，概率但预示，组成为，通过对高斯态操作条件制备技术使用测量诱导的非线性。在这里，两个非高斯状态，单光子态和相干态的叠加，使用两个不同的相位匹配参量振荡器作为第一资源，我们的细节这一代的协议。这项技术使实现高逼真度与良好控制的时空模式的目标状态和发电状态的。

对于II型OPO和高保真单光子态的产生： 在预示着状态的断层重建示于图2，其中所显示的重建的密度矩阵和相应的Wigner函数的对角元素。没有任何损失改正的，预示着国家呈现出单光子成分高达78％。考虑到整体的检测亏损（15％），状态达到91％与单光子状态的保真度。双光子元件，其导致从多光子对产生的下变频的过程中，被限制在3％左右。 对于I型OPO和CSS...

Watch this Scientific Journal Video about Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators at JoVE.com

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

我们描述了可靠的新一代移动光学领域，包括单光子态和相干态的叠加态，使用的非经典光通过光学参量振荡器发出的操作条件制备方法的非高斯状态。 I型和II型相位匹配的振荡器被认为与通用程序，例如所需要的频率滤波或零差检波的高效率的量子状态的表征，是详细。

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 ...

quantum-state-engineering-light-with-continuous-wave-optical

Research

Education

JoVE Core

JoVE Journal

Electrical Engineering

Engineering

Unit 1

Transient and Steady-state Response Analysis

SCIENTISTS IN ACTION

14.4K 次观看.  Université Pierre et Marie Curie, Ecole Normale Supérieure, CNRS. 我们描述了可靠的新一代移动光学领域，包括单光子态和相干态的叠加态，使用的非经典光通过光学参量振荡器发出的操作条件制备方法的非高斯状态。 I型和II型相位匹配的振荡器被认为与通用程序，例如所需要的频率滤波或零差检波的高效率的量子状态的表征，是详细。 

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

Quasi-light Storage for Optical Data Packets

Today's telecommunication is based on optical packets which transmit the information in optical fiber networks around the world. Currently, the processing of the signals is done in the electrical domain. Direct storage in the optical domain would avoid the transfer of the packets to the electrical and back to the optical domain in every network node and, therefore, increase the speed and possibly reduce the energy consumption of telecommunications. However, light consists of photons which propagate with the speed of light in vacuum. Thus, the storage of light is a big challenge. There exist some methods to slow down the speed of the light, or to store it in excitations of a medium. However, these methods cannot be used for the storage of optical data packets used in telecommunications networks. Here we show how the time-frequency-coherence, which holds for every signal and therefore for optical packets as well, can be exploited to build an optical memory. We will review the background and show in detail and through examples, how a frequency comb can be used for the copying of an optical packet which enters the memory. One of these time domain copies is then extracted from the memory by a time domain switch. We will show this method for intensity as well as for phase modulated signals.

The article describes a procedure to store optical data packets with an arbitrary modulation, wavelength, and data rate. These packets are the basis of modern telecommunications.

准光存储光学数据包

Today's telecommunication is based on optical packets which transmit the information in optical fiber networks around the world. Currently, the processing ...

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 ...

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots

A quantum computer is a computer composed of quantum bits (qubits) that takes advantage of quantum effects, such as superposition of states and entanglement, to solve certain problems exponentially faster than with the best known algorithms on a classical computer. Gate-defined lateral quantum dots on GaAs/AlGaAs are one of many avenues explored for the implementation of a qubit. When properly fabricated, such a device is able to trap a small number of electrons in a certain region of space. The spin states of these electrons can then be used to implement the logical 0 and 1 of the quantum bit. Given the nanometer scale of these quantum dots, cleanroom facilities offering specialized equipment- such as scanning electron microscopes and e-beam evaporators- are required for their fabrication. Great care must be taken throughout the fabrication process to maintain cleanliness of the sample surface and to avoid damaging the fragile gates of the structure. This paper presents the detailed fabrication protocol of gate-defined lateral quantum dots from the wafer to a working device. Characterization methods and representative results are also briefly discussed. Although this paper concentrates on double quantum dots, the fabrication process remains the same for single or triple dots or even arrays of quantum dots. Moreover, the protocol can be adapted to fabricate lateral quantum dots on other substrates, such as Si/SiGe.

This paper presents a detailed fabrication protocol for gate-defined semiconductor lateral quantum dots on gallium arsenide heterostructures. These nanoscale devices are used to trap few electrons for use as quantum bits in quantum information processing or for other mesoscopic experiments such as coherent conductance measurements.

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 ...

Fabrication and Characterization of Disordered Polymer Optical Fibers for Transverse Anderson Localization of Light

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. The developed polymer optical fiber is composed of 80,000 strands of poly (methyl methacrylate) (PMMA) and polystyrene (PS) that are randomly mixed and drawn into a square cross section optical fiber with a side width of 250 &mu;m. Initially, each strand is 200 &mu;m in diameter and 8-inches long. During the mixing process of the original fiber strands, the fibers cross over each other; however, a large draw ratio guarantees that the refractive index profile is invariant along the length of the fiber for several tens of centimeters. The large refractive index difference of 0.1 between the disordered sites results in a small localized beam radius that is comparable to the beam radius of conventional optical fibers. The input light is launched from a standard single mode optical fiber using the butt-coupling method and the near-field output beam from the disordered fiber is imaged using a 40X objective and a CCD camera. The output beam diameter agrees well with the expected results from the numerical simulations. The disordered optical fiber presented in this work is the first device-level implementation of 2D Anderson localization, and can potentially be used for image transport and short-haul optical communication systems.

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. This microstructured fiber can transport a small localized beam with a radius that is comparable to the beam radius of conventional optical fibers.

无序横向安德森本地化光聚合物光纤的制备和表征

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. The developed ...

Fabrication of Uniform Nanoscale Cavities via Silicon Direct Wafer Bonding

Measurements of the heat capacity and superfluid fraction of confined 4He have been performed near the lambda transition using lithographically patterned and bonded silicon wafers. Unlike confinements in porous materials often used for these types of experiments3, bonded wafers provide predesigned uniform spaces for confinement. The geometry of each cell is well known, which removes a large source of ambiguity in the interpretation of data.
Exceptionally flat, 5 cm diameter, 375 &#181;m thick Si wafers with about 1 &#181;m variation over the entire wafer can be obtained commercially (from Semiconductor Processing Company, for example). Thermal oxide is grown on the wafers to define the confinement dimension in the z-direction. A pattern is then etched in the oxide using lithographic techniques so as to create a desired enclosure upon bonding. A hole is drilled in one of the wafers (the top) to allow for the introduction of the liquid to be measured. The wafers are cleaned2 in RCA solutions and then put in a microclean chamber where they are rinsed with deionized water4. The wafers are bonded at RT and then annealed at ~1,100 &#176;C. This forms a strong and permanent bond. This process can be used to make uniform enclosures for measuring thermal and hydrodynamic properties of confined liquids from the nanometer to the micrometer scale.

A method for permanently bonding two silicon wafers so as to realize a uniform enclosure is described. This includes wafer preparation, cleaning, RT bonding, and annealing processes. The resulting bonded wafers (cells) have uniformity of enclosure ~1%1,2. The resulting geometry allows for measurements of confined liquids and gasses.

通过硅直接晶圆粘接制造均匀纳米级腔

Measurements of the heat capacity and superfluid fraction of confined 4He have been performed near the lambda transition using lithographically patterned ...

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 ...

Fabrication and Testing of Microfluidic Optomechanical Oscillators

Cavity optomechanics experiments that parametrically couple the phonon modes and photon modes have been investigated in various optical systems including microresonators. However, because of the increased acoustic radiative losses during direct liquid immersion of optomechanical devices, almost all published optomechanical experiments have been performed in solid phase. This paper discusses a recently introduced hollow microfluidic optomechanical resonator. Detailed methodology is provided to fabricate these ultra-high-Q microfluidic resonators, perform optomechanical testing, and measure radiation pressure-driven breathing mode and SBS-driven whispering gallery mode parametric vibrations. By confining liquids inside the capillary resonator, high mechanical- and optical- quality factors are simultaneously maintained.

Parametric optomechanical excitations have recently been experimentally demonstrated in microfluidic optomechanical resonators by means of optical radiation pressure and stimulated Brillouin scattering. This paper describes the fabrication of these microfluidic resonators along with methodologies for generating and verifying optomechanical oscillations.

制造和微流控光机振荡器测试

Cavity optomechanics experiments that parametrically couple the phonon modes and photon modes have been investigated in various optical systems including ...

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 ...

Fabrication of White Light-emitting Electrochemical Cells with Stable Emission from Exciplexes

The authors present an approach for fabricating stable white light emission from polymer light-emitting electrochemical cells (PLECs) having an active layer which consists of blue-fluorescent poly(9,9-di-n-dodecylfluorenyl-2,7-diyl) (PFD) and &#960;-conjugated triphenylamine molecules. This white light emission originates from exciplexes formed between PFD and amines in electronically excited states. A device containing PFD, 4,4&#39;,4&#39;&#39;-tris[2-naphthyl(phenyl)amino]triphenylamine (2-TNATA), Poly(ethylene oxide) and K2CF3SO3 showed white light emission with Commission internationale de l&#39;&#233;clairage (CIE) coordinates of (0.33, 0.43) and a Color Rendering Index (CRI) of Ra = 73 at an applied voltage of 3.5 V. Constant voltage measurements showed that the CIE coordinates of (0.27, 0.37), Ra of 67, and the emission color observed immediately after application of a voltage of 5 V were nearly unchanged and stable after 300 sec.

The authors present a method for fabricating stable white-light-emitting electrochemical cells utilizing emission from exciplexes formed between a blue-emitting fluorene polymer and aromatic amines.

白的制造发光电化学细胞与来自激发络合物稳定的发射

The authors present an approach for fabricating stable white light emission from polymer light-emitting electrochemical cells (PLECs) having an active ...

Scanning Light Scattering Profiler (SLPS) Based Methodology to Quantitatively Evaluate Forward and Backward Light Scattering from Intraocular Lenses

The scanning light scattering profiler (SLSP) methodology has been developed for the full-angle quantitative evaluation of forward and backward light scattering from intraocular lenses (IOLs) using goniophotometer principles. This protocol describes the SLSP platform and how it employs a 360&#176; rotational photodetector sensor that is scanned around an IOL sample while recording the intensity and location of scattered light as it passes through the IOL medium. The SLSP platform can be used to predict, non-clinically, the propensity for current and novel IOL designs and materials to induce light scatter. Non-clinical evaluation of light scattering properties of IOLs can significantly reduce the number of patient complaints related to unwanted glare, glistening, optical defects, poor image quality, and other phenomena associated with the unintended light scattering. Future studies should be conducted to correlate SLSP data with clinical results to help identify which measured light scatter is most problematic for patients that have undergone cataract surgery subsequent to IOL implantation.

Scanning Light Scattering Profiler SLPS Based Methodology to Quantitatively Evaluate Forward and Backward Light Scattering from Intraocular Lenses

This protocol describes the scanning light scattering profiler (SLSP) that enables the full-angle quantitative evaluation of forward and backward scattering of light from intraocular lenses (IOLs) using goniophotometer principles.

基于扫描光散射分析器（SLPS）的方法来量化评估来自眼内镜的前向和后向光散射

The scanning light scattering profiler (SLSP) methodology has been developed for the full-angle quantitative evaluation of forward and backward light ...