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Title: Valley splitting of Si/Si1-xGex heterostructures in tilted magnetic fields.

Abstract

We have investigated the valley splitting of two-dimensional electrons in high-quality Si/Si{sub 1-x}Ge{sub x} heterostructures under tilted magnetic fields. For all the samples in our study, the valley splitting at filling factor {nu} = 3 ({Delta}{sub 3}) is significantly different before and after the coincidence angle, at which energy levels cross at the Fermi level. On both sides of the coincidence, a linear dependence of {Delta}{sub 3} on the electron density was observed, while the slope of these two configurations differs by more than a factor of 2. We argue that screening of the Coulomb interaction from the low-lying filled levels, which also explains the observed spin-dependent resistivity, is responsible for the large difference of {Delta}{sub 3} before and after the coincidence.

Authors:
;  [1];  [1];  [2];  [3];  [2];  [2];  [3];  [2]
  1. (Universitat Linz, Austria)
  2. (Princeton University, Princeton, NJ)
  3. (UCLA, Los Angeles, CA)
Publication Date:
Research Org.:
Sandia National Laboratories
Sponsoring Org.:
USDOE
OSTI Identifier:
952152
Report Number(s):
SAND2006-0943J
TRN: US200913%%330
DOE Contract Number:
AC04-94AL85000
Resource Type:
Journal Article
Resource Relation:
Journal Name: Proposed for publication in Physical Review B.
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; SILICON; GERMANIUM SILICIDES; ELECTRON DENSITY; ENERGY LEVELS; FERMI LEVEL; MAGNETIC FIELDS

Citation Formats

Pan, Wei, Schaffler, F., Muhlberger, M., Lyon, S., Xie, Ya-Hong, Lai, K. W., Tsuri, D., Liu, J., and Lu, T.M. Valley splitting of Si/Si1-xGex heterostructures in tilted magnetic fields.. United States: N. p., 2006. Web.
Pan, Wei, Schaffler, F., Muhlberger, M., Lyon, S., Xie, Ya-Hong, Lai, K. W., Tsuri, D., Liu, J., & Lu, T.M. Valley splitting of Si/Si1-xGex heterostructures in tilted magnetic fields.. United States.
Pan, Wei, Schaffler, F., Muhlberger, M., Lyon, S., Xie, Ya-Hong, Lai, K. W., Tsuri, D., Liu, J., and Lu, T.M. Sun . "Valley splitting of Si/Si1-xGex heterostructures in tilted magnetic fields.". United States. doi:.
@article{osti_952152,
title = {Valley splitting of Si/Si1-xGex heterostructures in tilted magnetic fields.},
author = {Pan, Wei and Schaffler, F. and Muhlberger, M. and Lyon, S. and Xie, Ya-Hong and Lai, K. W. and Tsuri, D. and Liu, J. and Lu, T.M.},
abstractNote = {We have investigated the valley splitting of two-dimensional electrons in high-quality Si/Si{sub 1-x}Ge{sub x} heterostructures under tilted magnetic fields. For all the samples in our study, the valley splitting at filling factor {nu} = 3 ({Delta}{sub 3}) is significantly different before and after the coincidence angle, at which energy levels cross at the Fermi level. On both sides of the coincidence, a linear dependence of {Delta}{sub 3} on the electron density was observed, while the slope of these two configurations differs by more than a factor of 2. We argue that screening of the Coulomb interaction from the low-lying filled levels, which also explains the observed spin-dependent resistivity, is responsible for the large difference of {Delta}{sub 3} before and after the coincidence.},
doi = {},
journal = {Proposed for publication in Physical Review B.},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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