InAs-AlSb quantum wells in tilted magnetic fields

Abstract

InAs-AlSb quantum wells are investigated by transport experiments in magnetic fields tilted with respect to the sample normal. Using the coincidence method we find for magnetic fields up to 28 T that the spin splitting can be as large as 5 times the Landau splitting. We find a value of the g-factor of |g| ≈ 13. For small even-integer filling factors the corresponding minima in the Shubnikov-de Haas oscillations cannot be tuned into maxima for arbitrary tilt angles. This indicates the anti-crossing of neighboring Landau and spin levels. Furthermore we find for particular tilt angles a crossover from even-integer dominated Shubnikov-de Haas minima to odd-integer minima as a function of magnetic field.73. 50.-h, 72.20.-i, 72.90.+y

Magnetotransport in high-g-factor low-density two-dimensional electron systems confined inIn0.75Ga0.25Desrat1, Giazotto2, Pellegrini3 et al. 2004Phys. Rev. B354260View full textAdd to dashboardCite

“…We see that the data points, including those obtained at different gate voltages (different densities), suggest a linear dependence vs B ⊥ similar to what was reported in [25] and discussed in [26]. From these data we conclude that, even for InGaAs-based systems with large In concentration, the electron-electron interaction terms play a dominant role in determining the magnetic transitions at low filling factors, unlike previous studies on InAs systems characterized by larger electron densities [14].…”

“…In addition, the presence of a large Rashba coupling could yield new coherent Landau level configurations close to coincidence as predicted in Refs. [12,13] on 2DESs confined in InAs/InSb, however, showed no evidence of electron-electron interaction effects presumably due to a combination of large electron density (above 6 × 10 11 cm−2) and relatively low mobility [14].…”

“…However, several recent papers also reported g-factor values strongly reduced compared to the theoretical ones. For instance, bare g-factors of -13, -8.7 or -6 have been reported in InAs quantum wells [14,21,22] which are far from the bulk value of around -15. It must be stressed that in the present experiments the orbital effect of the in-plane field becomes important at large tilt angles and may contribute to the reduction of g * .…”

Tunable effectivegfactor in InAs nanowire quantum dots

“…In measurements on InAs-based two-dimensional electron systems, values from g * = −1 to g * = −13 have been found experimentally depending on magnetic field direction [18], quantum well width [15] and barrier composition [15,17] and gate tunability of g * has been demonstrated [17,19]. Investigations on self-assembled InAs QDs using magnetotunneling and capacitance spectroscopy have revealed anisotropic g-factors with values from +0.5 to +1.6 [20,21].…”

Rashba precession in quantum wires with interaction

“…In InAs the magnetic energy B translates quite accurately as 1 Ry per Tesla when taking the g-factor [31] as |g| = 13. Assuming again K σ ≈ 1 yields…”