Terahertz quantum Hall effect for spin-split heavy-hole gases in strained Ge quantum wells. (21st November 2016)

• Record Type: Journal Article
• Authors: Failla, M; Keller, J; Scalari, G; Maissen, C; Faist, J; Reichl, C; Wegscheider, W; Newell, O J; Leadley, D R; Myronov, M; Lloyd-Hughes, J
• Is Part Of: New journal of physics. Volume 18:Number 11(2016:Nov.)
• Publication Date: 2016-11-21
• Subjects: terahertz -- quantum Hall effect -- germanium -- spin–orbit -- strain -- quantum well; Physics -- Periodicals; Physics; Periodicals; 530.05
• DOI: 10.1088/1367-2630/18/11/113036
• Languages: English
• ISSNs: 1367-2630

Abstract

Abstract: Spin-split heavy-hole gases in strained germanium quantum wells were characterized by polarisation-resolved terahertz time-domain spectroscopy. Effective masses, carrier densities, g-factors, transport lifetimes, mobilities and Rashba spin-splitting energies were evaluated, giving quantitative insights into the influence of strain. The Rashba coefficient was found to lower for samples with higher biaxial compressive strain, while heavy-hole mobilities were enhanced to over 1.5 × 10 6 cm 2 V −1 s −1 at 3 K. This high mobility enabled the observation of the optical quantum Hall effect at terahertz frequencies for spin-split two-dimensional heavy-holes, evidenced as plateaux in the transverse magnetoconductivity at even and odd filling factors.