Electron Dynamics in a Coupled Quantum Point Contact Structure with a Local Magnetic Moment.pdf

Electron Dynamics in a Coupled Quantum Point Contact Structure with a Local Magnetic Moment ∗ 4 Vadim I. Puller and Lev G. Mourokh 0 0 2 Department of Physics and Engineering Physics, y Stevens Institute of Technology, Hoboken, New Jersey 07030, USA a M A. Shailos and J. P. Bird 1 3 Department of Electrical Engineering and Center for Solid State Electronics Research, ] l e Arizona State University, Tempe, Arizona, 85287-5706, USA - r t Abstract s . t a We develop a theoretical model for the description of electron dynamics in coupled quantum m - wires when the local magnetic moment is formed in one of the wires. We employ a single-particle d n Hamiltonian that takes account of the specific geometry of potentials defining the structure as well o c as electron scattering on the local magnetic moment. The equations for the wave functions in both [ 1 wires are derived and the approach for their solution is discussed. We determine the transmission v 5 coefficient and conductance of the wire having the local magnetic moment and show that our 0 7 description reproduces the experimentally observed features. 5 0 4 0 / t a m - d n o c : v i X r a ∗ Based on work presented at 2004 IEEE NTC Quantum Device Technology Workshop 1 I. INTRODUCTION The low-temperature conductance of quantum point contacts (QPCs) is well known to 2 be quantized in units of 2e /h, a phenomenon that can be explained in terms of a simple transmission (Landauer)