We study magneto-transport through a weakly open circular microstructure in the perpendicular weak magnetic fields by a semiclassical approximation within the framework of the Fraunhofer diffraction effect at the lead...We study magneto-transport through a weakly open circular microstructure in the perpendicular weak magnetic fields by a semiclassical approximation within the framework of the Fraunhofer diffraction effect at the lead openings.It is found that the peak positions of the transmission power spectrum can be related to simple trajectories according to classical dynamics.Moreover,we formulate the fluctuations in the transmission amplitude as functions of both the wave number k and the magnetic field B in terms of different classical trajectories,and the Aharonov-Bohm phase of the directed areas enclosed by these trajectories that reflect the quantum interference effect.展开更多
We use a semiclassical approximation to study the transport through the weakly open chaotic Sinai quantum billiards which can be considered as the schematic of a Sinai mesoscopic device,with the diffractive scattering...We use a semiclassical approximation to study the transport through the weakly open chaotic Sinai quantum billiards which can be considered as the schematic of a Sinai mesoscopic device,with the diffractive scatterings at the lead openings taken into account.The conductance of the ballistic microstructure which displays universal fluctuations due to quantum interference of electrons can be calculated by Landauer formula as a function of the electron Fermi wave number,and the transmission amplitude can be expressed as the sum over all classical paths connecting the entrance and the exit leads.For the Sinai billiards,the path sum leads to an excellent numerical agreement between the peak positions of power spectrum of the transmission amplitude and the corresponding lengths of the classical trajectories,which demonstrates a good agreement between the quantum theory and the semiclassical theory.展开更多
基金the National Natural Science Foundation of China under Grant Nos 10774093 and 10374061.
文摘We study magneto-transport through a weakly open circular microstructure in the perpendicular weak magnetic fields by a semiclassical approximation within the framework of the Fraunhofer diffraction effect at the lead openings.It is found that the peak positions of the transmission power spectrum can be related to simple trajectories according to classical dynamics.Moreover,we formulate the fluctuations in the transmission amplitude as functions of both the wave number k and the magnetic field B in terms of different classical trajectories,and the Aharonov-Bohm phase of the directed areas enclosed by these trajectories that reflect the quantum interference effect.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10804064 and 10774093)
文摘We use a semiclassical approximation to study the transport through the weakly open chaotic Sinai quantum billiards which can be considered as the schematic of a Sinai mesoscopic device,with the diffractive scatterings at the lead openings taken into account.The conductance of the ballistic microstructure which displays universal fluctuations due to quantum interference of electrons can be calculated by Landauer formula as a function of the electron Fermi wave number,and the transmission amplitude can be expressed as the sum over all classical paths connecting the entrance and the exit leads.For the Sinai billiards,the path sum leads to an excellent numerical agreement between the peak positions of power spectrum of the transmission amplitude and the corresponding lengths of the classical trajectories,which demonstrates a good agreement between the quantum theory and the semiclassical theory.
