Giant g-factors and fully spin-polarized states in metamorphic short-period InAsSb/InSb superlattices

Abstract

Realizing a large Landé g-factor of electrons in solid-state materials has long been thought of as a rewarding task as it can trigger abundant immediate applications in spintronics and quantum computing. Here, by using metamorphic InAsSb/InSb superlattices (SLs), we demonstrate an unprecedented high value of g ≈ 104, twice larger than that in bulk InSb, and fully spin-polarized states at low magnetic fields. In addition, we show that the g-factor can be tuned on demand from 20 to 110 via varying the SL period. The key ingredients of such a wide tunability are the wavefunction mixing and overlap between the electron and hole states, which have drawn little attention in prior studies. Our work not only establishes metamorphic InAsSb/InSb as a promising and competitive material platform for future quantum devices but also provides a new route toward g-factor engineering in semiconductor structures.

Quantum transport in InSb quantum well devices: progress and perspective

“…Optical measurements on bulk material have revealed an effective g-factor exceeding 100 when the Sb composition approaches 63% [83]. Furthermore, the g-factor has been reported to be tunable between 20 and 110 in InAsSb/InSb superlattices by altering the superlattice period [84]. Additionally, this superlattice exhibits signatures of a Dirac energy spectrum and inverted band gap, as observed with angle-resolved photoemission spectroscopy measurements [85,86].…”

The discovery of three-dimensional Van Hove singularity

“…Thus, the discussed exchange interaction offers a promising mechanism to experimentally realize the 3D VHS. The proposed physics might be detected by magneto-infrared spectroscopy, an effective optical technique to probe the evolution of the electronic states under the magnetic field [53][54][55][56][57][58] .…”