相关论文: Anamolous conductance plateau in an asymmetrically…
We report the observation of an anomalous conductance plateau near G = 0.5 G0 (G0 = 2e2/h) in asymmetrically biased AlGaAs/GaAs quantum point contacts (QPCs), with in-plane side gates in the presence of lateral spin-orbit coupling. This is…
The observation of a 0.5 conductance plateau in asymmetrically biased quantum point contacts with in-plane side gates has been attributed to the onset of spin-polarized current through these structures. For InAs quantum point contacts with…
Apart from usual quantization steps on the ballistic conductance of a quasi-one-dimensional conductor, an additional plateau-like feature appears at a fraction of about 0.7 below the first conductance step in GaAs-based quantum point…
The anomalous 0.5 and 0.7 conductance plateaus in quantum point contacts in zero magnetic field are analyzed within a phenomenological model. The model utilizes the Landauer-Buttiker formalism and involves enhanced spin correlations and…
A non-equilibrium Green function formalism (NEGF) is used to study the conductance of a side-gated quantum point contact (QPC) in the presence of lateral spin-orbit coupling (LSOC). A small difference of bias voltage between the two side…
A Quantum Point Contact (QPC) causes a one-dimensional constriction on the spatial potential landscape of a two-dimensional electron system. By tuning the voltage applied on a QPC at low temperatures the resulting regular step-like electron…
We report an experimental study on the shot noise as well as the dc transport properties of a quantum point contact (QPC) whose conductance anomaly can be tuned electrostatically by the gate electrodes. By controlling the single QPC so that…
We calculate the non-linear conductance of a quantum point contact using the non-equilibrium Greens function technique within the Hartree approximation of spinless electrons. We quantitative reproduce the 0.25-anomaly in the differential…
The unexpected "0.7" plateau of conductance quantisation is usually observed for ballistic one-dimensional devices. In this work we study a quasi-ballistic quantum wire, for which the disorder induced backscattering reduces the conductance…
We study one-dimensional itinerant electron models with ferromagnetic coupling to investigate the origin of 0.7 anomaly in quantum point contacts. Linear conductance calculations from the quantum Monte Carlo technique for spin interactions…
Quantum point contacts implemented in p-type GaAs/AlGaAs heterostructures are investigated by low-temperature electrical conductance spectroscopy measurements. Besides one-dimensional conductance quantization in units of $2e^{2}/h$ a…
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,…
We have developed a novel technique for detection of spin polarization with a quantum dot weakly coupled to the objective device. The disturbance to the object in this technique is very small since the detection is performed through…
Electron charge transport through a quantum point contact (QPC) driven by an asymmetric spin bias is studied. A large charge current is induced when the transmission coefficient of the QPC jumps from one integer plateau to the next.…
The 0.7 (2e^2/h) conductance anomaly is studied in strongly confined, etched GaAs/GaAlAs quantum point contacts, by measuring the differential conductance as a function of source-drain and gate bias as well as a function of temperature. We…
Most quantum point contacts (QPCs) fabricated in high-mobility 2D electron gases show a zero-bias conductance peak near pinchoff, but the origin of this peak remains a mystery. Previous experiments have primarily focused on the zero-bias…
We have observed hysteresis between the forward and reverse sweeps of a common mode bias applied to the two in-plane side gates of an asymmetrically biased GaAs quantum point contact. The size of the hysteresis loop increases with the…
A non-equilibrium Green's function formalism is used to study in detail the ballistic conductance of asymmetrically biased side-gated quantum point contacts (QPCs) in the presence of lateral spin-orbit coupling and electron-electron…
We analyze the conductance of the quantum point contact containing large localized spin J. The additional plateau is formed on a ballistic conductance staircase if only one propagating channel is rendered conducting. The conductance value…
We study the anomalous conductance plateau around $G = 0.7(2e^{2}/h)$ and the zero-bias anomaly in ballistic hole quantum wires with respect to in-plane magnetic fields applied parallel $B_{\parallel}$ and perpendicular $B_{\perp}$ to the…