Related papers: High-quality quantum point contact in two-dimensio…
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,…
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…
We have studied ballistic transport in a 1D channel formed using surface gate techniques on a back-gated, high-mobility, bilayer 2D hole system. At millikelvin temperatures, robust conductance quantization is observed in the quantum wire…
Quantum point contact devices are indispensable tools for probing the edge structure of the fractional quantum Hall (FQH) states. Recent observations of quantized conductance plateaus accompanied by shot noise in such devices, as well as…
Strong spin-orbit coupling, the resulting large $g$ factor, and small effective mass make InAs an attractive material platform for inducing topological superconductivity. The surface Fermi level pinning in the conduction band enables highly…
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…
The $\nu = 2/3$ fractional quantum Hall state is the hole-conjugate state to the primary Laughlin $\nu = 1/3$ state. We investigate transmission of edge states through quantum point contacts fabricated on a GaAs/AlGaAs heterostructure…
We analyze the fractional quantization of the ballistic conductance associated with the light and heavy holes bands in Si, Ge and GaAs systems. It is shown that the formation of the localized hole state in the region of the quantum point…
We report an experimental study of quantum point contacts defined in a high-quality strained germanium quantum well with layered electric gates. At zero magnetic field, we observe quantized conductance plateaus in units of 2$e^2/h$.…
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…
We report on the fabrication and electronic transport characterisation of Schottky-gated strongly confined Si/SiGe quantum point contacts (QPC). At zero magnetic field and T=450mK the QPC conductance as a function of gate voltage shows a…
We calculate the conductance of a ballistic point contact to a superconducting wire, produced by the s-wave proximity effect in a semiconductor with spin-orbit coupling in a parallel magnetic field. The conductance G as a function of…
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…
The conductance quantization and shot noise below the first conductance plateau $G_0 = 2e^2/h$ are measured in a quantum point contact fabricated in a GaAs/AlGaAs tunnel-coupled double quantum well. From the conductance measurement, we…
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…
We fabricated strongly confined Schottky-gated quantum point contacts by etching Si/SiGe heterostructures and observed intriguing conductance quantization in units of approximately 1e2/h. Non-linear conductance measurements were performed…
We report on developing split-gate quantum point contacts (QPCs) that have a tunable length for the transport channel. The QPCs were realized in a GaAs/AlGaAs heterostructure with a two- dimensional electron gas (2DEG) below its surface.…
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…
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…
We studied theoretically ballistic electronic transport in a proposed mesoscopic structure - Quantum Cable. Our results demonstrated that Qauntum Cable is a unique structure for the study of mesoscopic transport. As a function of Fermi…