2006/01/27 by Keji Lai, K. Lai, Tzu‐Ming Lu +12 · 2 citations
Engineering · Physics and Astronomy · #Advancements in Semiconductor Devices and Circuit Design #Quantum and electron transport phenomena #Semiconductor materials and devices #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.73.161301
published as Phys. Rev. B 73, 161301(R) (2006) · REVTEX 4 pages, 4 figures
arxiv created 2006/01/27 · openalex publication_date 2006/04/07 · arxiv updated 2009/12/01 · openalex created_date 2020/05/13 · openalex updated_date 2026/07/28
We have investigated the valley splitting of two-dimensional electrons in high-quality Si∕Si_1\ensuremath-xGex heterostructures under tilted magnetic fields. For all the samples in our study, the valley splitting at filling factor \ensuremathν=3 (\ensuremathΔ3) 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 \ensuremathΔ3 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 \ensuremathΔ3 before and after the coincidence.