Title :
Relaxation oscillation simulations and dilute magnetic semiconductor RTDs
Author_Institution :
Hartford Univ., West Hartford, CT, USA
Abstract :
A robust transient Wigner distribution function simulation procedure implemented for studying relaxation oscillations in resonant tunneling structures is applied to structures in which the barriers and/or quantum well is designed with dilute magnetic semiconductors (DMS). The function of the DMS layers is to provide a means, in the presence of an external magnetic field, to change the relative population of spin-up and spin-down carriers. This population dependence means that a magnetic field can control the current voltage peak-to-valley ratio and consequently the maximum frequency of self-excited oscillations. These simulations permit the exploration of design principles for DMS relaxation oscillators. In the present study they are used to explore the magnetic field dependence of the spin-up and spin-down charge distributions as a function of bias.
Keywords :
Wigner distribution; carrier density; magnetic devices; relaxation oscillators; resonant tunnelling diodes; semiconductor device models; semimagnetic semiconductors; spin dynamics; charge distributions; current voltage peak; dilute magnetic semiconductor RTD; magnetic field dependence; population dependence; quantum well; relaxation oscillation simulations; resonant tunneling structures; robust transient Wigner distribution function simulation; self-excited oscillations; spin-down carriers; spin-up carriers; Circuits; Frequency; Magnetic fields; Magnetic materials; Magnetic resonance; Magnetic semiconductors; Oscillators; Resonant tunneling devices; Robustness; Wave functions;
Conference_Titel :
Nanotechnology, 2004. 4th IEEE Conference on
Print_ISBN :
0-7803-8536-5
DOI :
10.1109/NANO.2004.1392444