TY - JOUR

T1 - Stochastic analysis of surface roughness models in quantum wires

AU - Nedjalkov, Mihail

AU - Ellinghaus, Paul

AU - Weinbub, Josef

AU - Sadi, Toufik

AU - Asenov, Asen

AU - Dimov, Ivan

AU - Selberherr, Siegfried

PY - 2018/7

Y1 - 2018/7

N2 - We present a signed particle computational approach for the Wigner transport model and use it to analyze the electron state dynamics in quantum wires focusing on the effect of surface roughness. Usually surface roughness is considered as a scattering model, accounted for by the Fermi Golden Rule, which relies on approximations like statistical averaging and in the case of quantum wires incorporates quantum corrections based on the mode space approach. We provide a novel computational approach to enable physical analysis of these assumptions in terms of phase space and particles. Utilized is the signed particles model of Wigner evolution, which, besides providing a full quantum description of the electron dynamics, enables intuitive insights into the processes of tunneling, which govern the physical evolution. It is shown that the basic assumptions of the quantum-corrected scattering model correspond to the quantum behavior of the electron system. Of particular importance is the distribution of the density: Due to the quantum confinement, electrons are kept away from the walls, which is in contrast to the classical scattering model. Further quantum effects are retardation of the electron dynamics and quantum reflection. Far from equilibrium the assumption of homogeneous conditions along the wire breaks even in the case of ideal wire walls.

AB - We present a signed particle computational approach for the Wigner transport model and use it to analyze the electron state dynamics in quantum wires focusing on the effect of surface roughness. Usually surface roughness is considered as a scattering model, accounted for by the Fermi Golden Rule, which relies on approximations like statistical averaging and in the case of quantum wires incorporates quantum corrections based on the mode space approach. We provide a novel computational approach to enable physical analysis of these assumptions in terms of phase space and particles. Utilized is the signed particles model of Wigner evolution, which, besides providing a full quantum description of the electron dynamics, enables intuitive insights into the processes of tunneling, which govern the physical evolution. It is shown that the basic assumptions of the quantum-corrected scattering model correspond to the quantum behavior of the electron system. Of particular importance is the distribution of the density: Due to the quantum confinement, electrons are kept away from the walls, which is in contrast to the classical scattering model. Further quantum effects are retardation of the electron dynamics and quantum reflection. Far from equilibrium the assumption of homogeneous conditions along the wire breaks even in the case of ideal wire walls.

KW - Electron state dynamics

KW - Quantum wire

KW - Signed particles

KW - Surface roughness

KW - Wigner transport model

UR - http://www.scopus.com/inward/record.url?scp=85044871947&partnerID=8YFLogxK

U2 - 10.1016/j.cpc.2018.03.010

DO - 10.1016/j.cpc.2018.03.010

M3 - Article

AN - SCOPUS:85044871947

SN - 0010-4655

VL - 228

SP - 30

EP - 37

JO - Computer Physics Communications

JF - Computer Physics Communications

ER -