1207.3402 (Rayda Gammag et al.)

Two-dimensional electron gas tilt-induced Landau level crossings    [PDF]

Rayda Gammag, Cristine Villagonzalo

Under a tilted magnetic field $\vec{B}$, a two-dimensional electron gas (2DEG) with Rashba and Zeeman interactions is considered. The eigenvalues and their degeneracies, derived for various tilt angles, show crossing-free levels except at very high tilt. In this region, the tilt angle becomes the dominant factor in tuning the spin-splitting energy gap rather than the strength of the spin-orbit interaction. Moreover, concomitant with the crossings are the beats found in the 2DEG density of states. The crossings from different levels occur consecutively at around $87^{\circ}$. Similar new observations in Shubnikov-de Haas experimental measurements by Hatke \textit{et al.} \cite{Hatke2012} attributed such phenomena to an in-plane magnetic field-induced increase in the effective mass. We show here that this behavior is inherent to a 2DEG where spin-orbit interaction and the in-plane magnetic field contribution are taken into account.

View original: http://arxiv.org/abs/1207.3402