الكتاب أشكر مايكل Lacerte حصول على الدعم الفني. MP-L. يعترف المعهد الكندي للأبحاث المتقدمة (CIFAR)، والعلوم الطبيعية والهندسة مجلس البحوث كندا (NSERC)، والمؤسسة الكندية للابتكارات (CFI) وفون للبحوث كيبيك - الطبيعة وتقنيات (FRQNT) للحصول على الدعم المالي. كانت ملفقة الجهاز المقدمة هنا في CRN2 وIMDQ المرافق، الذي تموله جزئيا NanoQuébec. لفقت من الغاليوم / AlGaAs الركيزة التي كتبها ZR اسيلفسكي من معهد العلوم المجهرية في مجلس القومي للبحوث كندا. JCL وCB-O. نعترف CRSNG وFRQNT للحصول على الدعم المالي.

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الكتاب ليس لديهم ما يكشف.

عملية المعروضة أعلاه يصف بروتوكول تلفيق نقطة الكم مزدوج قادرة على الوصول إلى النظام القليلة الإلكترون. ومع ذلك، قد المعلمات نظرا يختلف وفقا لنموذج ومعايرة المعدات المستخدمة. ولذلك، فإن المعلمات مثل جرعات عن التعرض أثناء الخطوات البريد شعاع وضوئيه يجب أن تكون محسوب?...

وقد وضعت الكم علم المعلومات على الكثير من الاهتمام من أي وقت مضى منذ أن تبين أن الخوارزميات الكمومية يمكن أن تستخدم في حل بعض المشاكل أضعافا مضاعفة أسرع من أفضل الخوارزميات الكلاسيكية المعروفة 1. مرشح واضح لبت الكم (و qubit) هو دوران إلكترون واحد محصورة في الكم نقطة نظرا لأنه هو نظام من مستويين. وقد اقترحت العديد من أبنية لتنفيذ نقاط الكم، بما في ذلك شبه الموصلة أسلاك 2، 3 أنابيب الكربون النانوية، نقاط الكم الذاتي تجميعها 4، وأشباه الموصلات عمودي 5 و 6 نقاط الكم الجانبي. نقاط الكم الجانبي بوابة المعرفة في الغاليوم / تم heterostructures AlGaAs ناجحة جدا بسبب تعدد استعمالاتها وعملية التصنيع الخاصة بهم هو محور هذه الورقة. في النقاط الكمومية الجانبية، والحبس من الإلكترونات في اتجاه عمودي على سطح العينة (Z اتجاه) طو يتحقق عن طريق اختيار الركيزة المناسبة. يعرض الغاليوم / AlGaAs heterostructure التحوير مخدر غاز الإلكترون ثنائية الأبعاد (2DEG) تقتصر على واجهة بين AlGaAs وطبقات الغاليوم. وتزرع هذه العينات بواسطة الجزيئية تناضد شعاع للحصول على كثافة منخفضة الشوائب التي، جنبا إلى جنب مع تقنية التضمين المنشطات، يؤدي إلى التنقل الإلكترون عالية في 2DEG. وتظهر التخطيطي لطبقات مختلفة من heterostructure وكذلك هيكل الفرقة في الشكل 1. وهناك حاجة إلى التنقل الإلكترون عالية في 2DEG لضمان تماسك الدول الإلكترونية على سطح كامل من الكم نقطة. تم شراؤها الركيزة المستخدمة في عملية التصنيع هو موضح أدناه من مجلس البحوث الوطني في كندا ويمثل كثافة الإلكترونات من 2.2 × 10 11 سم -2 والتنقل الإلكترون من 1.69 × 10 6 سم 2 / Vsec. الحبس من الإلكترونات في بارال الاتجاهاتويتحقق الحد الأدنى للانفجار على سطح العينة عن طريق وضع أقطاب معدنية على سطح الركيزة. عندما تترسب هذه الأقطاب على سطح العينة الغاليوم، تتشكل حواجز شوتكي 7. الفولتية السلبية المطبقة على مثل هذه الأقطاب يؤدي إلى الحواجز المحلية في 2DEG أدناه والتي الإلكترونات فقط مع ما يكفي من الطاقة يمكن أن يعبر. استنفاد 2DEG يحدث عند الجهد المطبق هو سلبي يكفي أن الإلكترونات لا يكون ما يكفي من الطاقة لعبور الحاجز. لذلك، عن طريق اختيار بعناية هندسة الأقطاب، فمن الممكن إلى اعتراض عدد صغير من الالكترونات بين المناطق المنضب من العينة. ويمكن تحقيق السيطرة على عدد من الإلكترونات على نقطة فضلا عن الطاقة نفق بين نقطة و2DEG في بقية عينة من صقل الفولتية على الأقطاب. ويرد التخطيطي للأقطاب البوابة والغاز الإلكترون المنضب في الشكل 2. تصميم لهياكل بوابة تشكيل نقطة فيspired من خلال تصميم المستخدمة من قبل بارثيل وآخرون. 8 للسيطرة، وتلا المعلومات فيما يتعلق بعدد الإلكترونات على النقطة، فمن المفيد للحث وقياس الحالي من خلال نقطة. يمكن أيضا أن يتم قراءات باستخدام نقطة الاتصال الكم (QPC)، الأمر الذي يتطلب أيضا الحالي من خلال 2DEG. يتم ضمان الاتصال بين مصادر 2DEG والجهد من قبل اتصالات أومية. هذه هي منصات المعدنية التي تنتشر من سطح العينة على طول الطريق وصولا الى 2DEG باستخدام معيار السريع الحرارية يصلب عملية 7 (انظر الشكلين 3A و 4B). لتجنب دوائر قصيرة بين المصدر والكفاءات، وحفرت على سطح العينة بحيث يتم استنفاد 2DEG في مناطق معينة ويضطر إلى السفر الحالية من خلال قنوات محددة معينة (انظر أرقام 3B و 4A). ويشار إلى المنطقة حيث لا يزال 2DEG لا يزال باسم &quot;ميسا&quot;. تفاصيل بروتوكول التالية عملية تلفيق كامل من نقطة بوابة المعرفة الوحشي الكم على الغاليوم / AlGaAs الركيزة. عملية غير قابلة للتطوير لأنه لا يزال هو نفسه بغض النظر إذا كان الجهاز قيد التجهيز هو، مزدوجة، أو ثلاثة أضعاف الكم نقطة واحدة أو حتى مجموعة من نقاط الكم. والتلاعب، والقياس، والنتائج لمضاعفة نقاط الكم ملفقة باستخدام هذا الأسلوب تمت مناقشتها في أقسام أخرى.

<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

كمبيوتر الكم هو جهاز كمبيوتر يتكون من بت الكم (المكدسة) أن يستفيد من آثار الكم، مثل تراكب من الدول وتشابك، من أجل حل بعض المشاكل أضعافا مضاعفة أسرع من أفضل الخوارزميات المعروفة على جهاز كمبيوتر الكلاسيكية. بوابة المعرفة من نقاط الكم الوحشي على الغاليوم / AlGaAs هي واحدة من العديد من السبل لاستكشاف تنفيذ و qubit. عندما ملفقة بشكل صحيح، مثل هذا الجهاز قادر على اعتراض عدد قليل من الإلكترونات في منطقة معينة من الفضاء. ويمكن بعد ذلك للولايات تدور هذه الإلكترونات أن تستخدم لتنفيذ المنطقية 0 و 1 من بت الكم. نظرا لحجم النانومتر من هذه النقاط الكمومية، مرافق غرف الأبحاث التي تقدم المعدات المتخصصة مثل المسح الضوئي والمجاهر الإلكترونية والبريد شعاع تبخر أنها لازمة لتصنيع بهم. يجب توخي الحذر الشديد في جميع مراحل عملية التصنيع للحفاظ على نظافة سطح العينة وإلى تجنب إتلاف بوابات الهشة للهيكل. هذه الورقةويقدم البروتوكول تلفيق مفصلة من بوابة المعرفة من نقاط الكم الجانبي من الرقاقة إلى جهاز العمل. كما ناقش بإيجاز أساليب توصيف وممثل النتائج. على الرغم من أن هذه الورقة تركز على مضاعفة نقاط الكم، عملية تلفيق لا يزال هو نفسه لنقطة واحدة أو ثلاثة أو حتى صفائف من النقاط الكمومية. وعلاوة على ذلك، فإن البروتوكول يمكن تكييفها لافتعال نقاط الكم الوحشي على ركائز أخرى، مثل سي / SiGe.

واحدة من الخطوات الحاسمة في عملية وصفها أعلاه هو النقش من ميسا (الخطوة 1). من المهم أن حفر ما يكفي لإزالة أدناه 2DEG مع تجنب overetching. ولذلك، فمن المستحسن استخدام الغاليوم معظم عينة وهمية لاختبار الحل النقش قبل تنفيذ حفر على الغاليوم / عينة AlGaAs. معدل حفر من الغاليوم / AlGaAs heteros...

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Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots

وتعرض هذه الورقة على بروتوكول تلفيق مفصلة لبوابة المعرفة من قبل أشباه الموصلات النقاط الكمومية الجانبية على heterostructures الغاليوم. وتستخدم هذه الأجهزة النانومترية الحجم إلى اعتراض بعض الإلكترونات للاستخدام كما بت الكم في معالجة المعلومات الكمومية أو لإجراء التجارب جرحشاعثزرحشرتاد أخرى مثل قياسات تصرف متماسك.

النانوية من بوابة المعرفة الغاليوم / AlGaAs الجانبي نقاط الكم

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

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Research

JoVE Journal

Engineering

16.0K Views.  Université de Sherbrooke. وتعرض هذه الورقة على بروتوكول تلفيق مفصلة لبوابة المعرفة من قبل أشباه الموصلات النقاط الكمومية الجانبية على heterostructures الغاليوم. وتستخدم هذه الأجهزة النانومترية الحجم إلى اعتراض بعض الإلكترونات للاستخدام كما بت الكم في معالجة المعلومات الكمومية أو لإجراء التج?...

Video: 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.

الكم النقاط المدمجة لواحدة جزيء التصوير

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

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.

التدرج صدى الذاكرة الكم في الحارة بخار الذرية

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.

تحليل الاتصال واجهات لأجهزة أسلاك متناهية الصغر واحدة الجاليوم

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.

البناء وتوصيف الخارجية تجويف ديود ليزر للفيزياء الذرية

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.

الدولة الكم هندسة الضوء مع استمرار موجة حدودي البصرية المذبذبات

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.

انتقائية المساحة تعديل السيليكون بلل السطح بواسطة الليزر النبضي للأشعة فوق البنفسجية تشعيع في البيئة السائلة

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.

السيليكون المعدنية أكسيد أشباه الموصلات الكم النقاط لالضخ وحيد الإلكترون

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.

قياس الكم التدخل في المصدر السيليكون الدائري الرنان فوتون

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.

طرق تجريبية لمحاصرة الأيونات باستخدام ميكروفابريكاتيد السطحية الفخاخ أيون

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.

صدى الأسفار نقطة الكم إينجاس في تجويف مستو متعامد الإثارة والكشف عنها باستخدام

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