Transcript Materials Computation Center R.M. Martin and J.P. Leburton

Materials Computation Center, University of Illinois
Duane Johnson and Richard Martin, NSF DMR-03-25939
New Monte Carlo Method for Interacting Electrons in Quantum Dot Devices
R. M. Martin (Physics) and J.P. Leburton (ECE)
Research Objectives: First-principles calculations of
the charge and spin states in semiconductor quantum
dots including all effects of material layers and patterned
metal gates in real devices.
Approach: Simulation of quantum many-body electron
system in semiconductor quantum dots by quantum Monte
Carlo (QMC) with all interactions and applied gate potentials
simulated by classical Green Function Monte Carlo
(GFMC).
Actual
device
Top View
Side view
Code Development: Thez code is integrated with the
MCC QMC tools package, which is freely available over the
web.
Significant Results: The first full calculations for
interacting electrons in real device geometries for
coupled quantum dots. The figures show the device
structure, the confining potential calculated by GFMC, and
the singlet-triplet energy difference calculated by QMC
and GFMC as a function of gate voltage.
Broader Impact: Controlled device design through
science, and cross-disciplinary trained students for industry.
Reliable integrated methods at the length/time scales for
actual devices. Tools for design of new devices and systems.
MCC website: http://www.mcc.uiuc.edu
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