相关论文: Zero-bias Anomaly of Quantum Point Contacts in the…
The integer quantized conductance of one-dimensional electron systems is a well understood effect of quantum confinement. A number of fractionally quantized plateaus are also commonly observed. They are attributed to many-body effects, but…
We report a zero-bias peak in the differential conductance of a Quantum Point Contact (QPC), which splits in an external magnetic field. The peak is observed over a range of device conductance values starting significantly below $2e^2/h$.…
The 0.7 conductance anomaly in the quantized conductance of trench etched GaAs quantum point contacts is studied experimentally. The temperature dependence of the anomaly measured with vanishing source-drain bias reveals the same activated…
Quantum point contacts exhibit mysterious conductance anomalies in addition to well known conductance plateaus at multiples of 2e^2/h. These 0.7 and zero-bias anomalies have been intensively studied, but their microscopic origin in terms of…
Majorana zero modes can appear at the wire ends of a 1D topological superconductor and manifest themselves as a quantized zero-bias conductance peak in the tunneling spectroscopy of normal-superconductor junctions. However, in…
Small differential conductance oscillations as a function of source-drain bias were observed and systematically studied in an asymmetric quantum point contact (QPC). These oscillations become significantly suppressed in a small in-plane…
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…
We have studied quantum wires using the Green's function technique and the density-functional theory, calculating the electronic structure and the conductance. All the numerics are implemented using the finite-element method with a…
A popular signature of Majorana bound states in topological superconductors is the zero-energy conductance peak with a height of $2e^2/h$. However, a similar zero energy conductance peak with almost the same height can also arise due to…
Linear conductance below $2e^2/h$ shows resonance peaks in highly asymmetric quantum point contacts (QPCs). As the channel length increases, the number of peaks also increases. At the same time, differential conductance exhibits zero bias…
The appearance and evolution of an anomalous conductance plateau at 0.4 (in units of 2e2/h) in an In0.52Al0.48As/InAs quantum point contact (QPC), in the presence of lateral spin-orbit coupling, has been studied at T=4.2K as a function of…
We study the negative correction to the quantized value $2e^2/h$ of the conductance of a quantum point contact due to the backscattering of electrons by acoustic phonons. The correction shows activated temperature dependence and also gives…
Self-consistent modelling based on local spin-density formalism is employed to calculate conductance of quantum point contacts at finite temperatures. The total electrostatic potential exhibits spin-dependent splitting, which persists at…
Features below the first conductance plateau in ballistic quantum point contacts (QPCs) are often ascribed to electron interaction and spin effects within the single mode limit. In QPCs with a highly asymmetric geometry, we observe sharp…
It has been suggested that a zero-bias conductance peak in quantum wires signifies the presence of Kondo spin-correlations, which might also relate to an intriguing 1D spin-effect known as the 0.7 structure. These zero-bias anomalies (ZBA)…
Probing an isolated Majorana zero mode is predicted to reveal a tunneling conductance quantized at $2e^2/h$ at zero temperature. Experimentally, a zero-bias peak (ZBP) is expected and its height should remain robust against relevant…
Effects of impurity scatterings on the conductance in normal-metal / $d$ wave superconductor junctions are discussed by using the single-site approximation. So far, the split of the zero-bias conductance peak has been believed to be an…
We develop a theory of the conductance of a quantum dot connected to two leads by single-mode quantum point contacts. If the contacts are in the regime of perfect transmission, the conductance shows no Coulomb blockade oscillations as a…
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…
Short length quantum wires (quantum contacts) exhibit a conductance structure at the value of conductance close to 0.7 \times 2e^2/h. The structure is also called the conductance anomaly. In longer contacts the structure evolves to the…