Multisubband transport and magnetic deflection of Fermi electron trajectories in three terminal junctions and rings

Abstract

We study the electron transport in three terminal junctions and quantum rings looking for the classical deflection of electron trajectories in the presence of intersubband scattering. We indicate that although the Aharonov-Bohm oscillations and the Lorentz force effects co-exist in the low subband transport, for higher Fermi energies a simultaneous observation of both effects is difficult and calls for carefully formed structures. In particular, in quantum rings with channels wider than the input lead the Lorentz force is well resolved but the Aharonov-Bohm periodicity is lost in chaotic scattering events. In quantum rings with equal lengths of the channels and T-shaped junctions the Aharonov-Bohm oscillations are distinctly periodic but the Lorentz force effects are not well pronounced. We find that systems with wedge-shaped junctions allow for observation of both the periodic Aharonov-Bohm oscillations and the magnetic deflection.

Braess paradox at the mesoscopic scale

“…17 In the present work, the propagation of the wave packet in Eq. (1) is calculated by using the split-operator technique 11,18,19 to perform successive applications of the time-evolution operator, i.e.…”

“…Several papers have reported calculations on wave packet propagation in nanostructured systems, [12][13][14][15] hence, a number of numerical techniques for this kind of calculation is available in the literature, such as the expansion of the time evolution operator in Chebyshev polynomials, 16 and Crank-Nicolson based techniques. 17 In the present work, the propagation of the wave packet in Eq. ( 1) is calculated by using the split-operator technique 11,18,19 to perform successive applications of the time-evolution operator, i.e.…”

A Quantum Trajectory Interpretation of Magnetic Resistance in Quantum Dots

“…On the other hand, quantum mechanical model for electron billiards was known as quantum billiards [7], in which moving point particles are replaced by waves. Quantum billiards are most convenient for illustrating the phenomenon of Fano interference [8] and its interplay with Aharonov-Bohm interference [9], which otherwise cannot be described by classical methods.…”

Current Control by Resonance Decoupling and Magnetic Focusing in Soft-Wall Billiards

“…Their transport properties are drastically altered by an externally applied magnetic field [18][19][20][21][22][23][24][25][26], and they therefore dominate the intense investigation of coherent magnetotransport in the mesoscopic regime, where quantum interference meets and overlaps with the notion of oriented paths. Specifically, generalized Aharonov-Bohm (AB) oscillations [27] from phase modulation of interfering states [19,23,28] combine with the Lorentz deflection [24,29,30] of electrons up to the formation of edge states [19,24,31].…”