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Related papers: Split-gate quantum point contacts with tunable cha…

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Quantum point contact or QPC -- a constriction in a semiconducting two-dimensional (2D) electron system with a quantized conductance -- has been found as the building block of novel spintronic, and topological electronic circuits. They can…

Charge carriers in the quantum Hall regime propagate via one-dimensional conducting channels that form along the edges of a two-dimensional electron gas. Controlling their transmission through a gate-tunable constriction, also called…

We propose a new device to create a tunable all-electric spin polarizer: a quantum point contact (QPC) with four gates -- two in-plane side gates in series. The first pair of gates, near the source, is asymmetrically biased to create spin…

Mesoscale and Nanoscale Physics · Physics 2015-06-15 J. Charles , N. Bhandari , J. Wan , M. Cahay , R. S. Newrock

One of the hallmark experiments of quantum transport is the observation of the quantized resistance in a point contact formed with split gates in GaAs/AlGaAs heterostructures. Being carried out on a single material, they represent in an…

Mesoscale and Nanoscale Physics · Physics 2018-09-12 Holger Thierschmann , Emre Mulazimoglu , Nicola Manca , Srijit Goswami , Teun M. Klapwijk , Andrea D. Caviglia

Here, we employ a numerical approach to investigate the transport and conductance characteristics of a quantum point contact. A quantum point contact is a narrow constriction of a width comparable to the electron wavelength defined in a…

Mesoscale and Nanoscale Physics · Physics 2015-12-08 G. Bilgec Akyüz , A. Siddiki

The prospect of coupling a two-dimensional (2D) semiconductor heterostructure to a superconductor opens new research and technology opportunities, including fundamental problems in mesoscopic superconductivity, scalable superconducting…

Quantum point contacts (QPC) are fundamental building blocks of nanoelectronic circuits. For their emission dynamics as well as for interaction effects such as the 0.7-anomaly the details of the electrostatic potential are important, but…

Mesoscale and Nanoscale Physics · Physics 2020-09-21 Max Geier , Jaan Freudenfeld , Jorge T. Silva , Vladimir Umansky , Dirk Reuter , Andreas D. Wieck , Piet W. Brouwer , Stefan Ludwig

Ge/SiGe quantum well heterostructures confining a high-mobility two-dimensional hole gas (2DHG) have emerged as a compelling platform for hybrid superconductor(S)-semiconductor(Sm) quantum devices. Here, we investigate the low-temperature…

We studied ballistic transport across a quantum point contact (QPC) defined in a high-quality, GaAs (311)A two-dimensional (2D) hole system using shallow etching and top-gating. The QPC conductance exhibits up to 11 quantized plateaus. The…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 J. Shabani , J. R. Petta , M. Shayegan

Electric-field effect control of two-dimensional electron gases (2-DEG) has enabled the exploration of nanoscale electron quantum transport in semiconductors. Beyond these classical materials, transition metal-oxide-based structures have…

Mesoscale and Nanoscale Physics · Physics 2019-03-29 A. Jouan , G. Singh , E. Lesne , D. C. Vaz , M. Bibes , A. Barthélémy , C. Ulysse , D. Stornaiuolo , M. Salluzzo , S. Hurand , J. Lesueur , C. Feuillet-Palma , N. Bergeal

Electrostatic gates are of paramount importance for the physics of devices based on high-mobility two-dimensional electron gas (2DEG) since they allow depletion of electrons in selected areas. This field-effect gating enables the…

Mesoscale and Nanoscale Physics · Physics 2015-09-23 K. Bennaceur , B. A. Schmidt , S. Gaucher , D. Laroche , M. P. Lilly , J. L. Reno , K. W. West , L. N. Pfeiffer , G. Gervais

Quantum point contacts (QPC) are the building blocks of quantum dot qubits and semiconducting quantum electrical metrology circuits. QPCs also make highly sensitive electrical amplifiers with the potential to operate in the quantum-limited…

Mesoscale and Nanoscale Physics · Physics 2023-11-27 Anusha Shanmugam , Prasanta Kumbhakar , Harikrishnan Sundaresan , Annu Anns Sunny , J L Reno , Madhu Thalakulam

We report experimental results on a quantum point contact (QPC) device formed in a wide AlAs quantum well where the two-dimensional electrons occupy two in-plane valleys with elliptical Fermi contours. To probe the closely-spaced,…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 O. Gunawan , B. Habib , E. P. De Poortere , M. Shayegan

We demonstrate a reconfigurable quantum dot gate architecture that incorporates two interchangeable transport channels. One channel is used to form quantum dots and the other is used for charge sensing. The quantum dot transport channel can…

Mesoscale and Nanoscale Physics · Physics 2015-06-29 D. M. Zajac , T. M. Hazard , X. Mi , K. Wang , J. R. Petta

Spatial confinement and manipulation of charged carriers in semiconducting nanostructures are essential for realizing quantum electronic devices. Gate-defined nanostructures made of two-dimensional (2D) semiconducting transition metal…

Mesoscale and Nanoscale Physics · Physics 2016-10-11 Ke Wang , Takashi Taniguchi , Kenji Watanabe , Philip Kim

Atomically precise graphene nanoribbons (GNRs) are increasingly attracting interest due to their largely modifiable electronic properties, which can be tailored by controlling their width and edge structure during chemical synthesis. In…

Recent theories suggest that the excitations of certain quantum Hall states may have exotic braiding statistics which could be used to build topological quantum gates. This has prompted an experimental push to study such states using…

Mesoscale and Nanoscale Physics · Physics 2015-06-25 J. B. Miller , I. P. Radu , D. M. Zumbuhl , E. M. Levenson-Falk , M. A. Kastner , C. M. Marcus , L. N. Pfeiffer , K. W. West

Gate-tunable high-mobility InSb/In_{1-x}Al_{x}Sb quantum wells (QWs) grown on GaAs substrates are reported. The QW two-dimensional electron gas (2DEG) channel mobility in excess of 200,000 cm^{2}/Vs is measured at T=1.8K. In asymmetrically…

We perform scanning-gate microscopy on a quantum-point contact. It is defined in a high-mobility two-dimensional electron gas of an AlGaAs/GaAs heterostructure, giving rise to a weak disorder potential. The lever arm of the scanning tip is…

Mesoscale and Nanoscale Physics · Physics 2012-02-21 S. Schnez , C. Rössler , T. Ihn , K. Ensslin , C. Reichl , W. Wegscheider

Electrostatically defined nanoscale devices on two-dimensional semiconductor heterostructures are the building blocks of various quantum electrical circuits. Owing to its atomically flat interfaces and the inherent two-dimensional nature,…

Mesoscale and Nanoscale Physics · Physics 2016-11-23 Chithra H. Sharma , Madhu Thalakulam
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