Pressure Dependence of Band Offsets in an InAs-GaSb Superlattice

Claessen, L. M.; Maan, J.C.; Altarelli, M.; Wyder, P.; Chang, L.L.; Esaki, L.

doi:10.1103/physrevlett.57.2556

Cited by 50 publications

(8 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It has been argued that hybridization model, or conduction-valence Landau level (LL) mixing, has an insignificant effect at high and low fields, 79 while the CR splitting in this paper occur only at magnetic fields higher than 14 T. In the literature, multiple absorptions were observed throughout and within nearly entire magnetic range investigated. [66][67][68][77][78][79][80][81][82][83][84][85][86][87][88] One may argue that the magnetic field range, where the CR splitting were observed in this paper, is in fact the "intermediate" field range, but it is very unlikely. It is essentially impossible to place an intermediate regime within the confine of the given system.…”

Section: Resultsmentioning

confidence: 75%

“…within the energy gap, which will definitely result in multiple modes at very low magnetic fields. [77][78][79][80][81][82][83][84][85]87,88 Another explanation for the lack of CR splitting at lower magnetic fields is that the interposed barrier layer suppresses the strength of the hybridization. No matter whether the FS is above the hole subbands or between the electron and hole subbands, hybridization in these samples is too weak to result in multiple modes even when the electron and hole LLs are aligned.…”

Section: Resultsmentioning

confidence: 99%

“…On one hand, the results suggest the formation of stable excitons by showing exciton's 1s − 2p internal transitions; 66-68 on the other hand, they were interpreted as the hybridization gap due to a mixing of the electron and hole wavefunctions. [77][78][79][80][81][82][83][84][85][86][87][88] Though most of the FIR investigation reveal multiple modes around CR in InAs/GaSb CQWs, only a single mode was observed up to 12 T and interpreted as electron-CR by Heitmann et al 89 Earlier studies in InAs/GaSb superlattice systems show electron CR, intersubband transitions and sometimes two absorptions near CR attributed to two occupied electron subbands. [90][91][92][93][94] More recent reports about the InAs/GaSb 2DEHS demonstrate results in favor of the hybridization gap interpretation.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Magneto-infrared modes in InAs-AlSb-GaSb coupled quantum wells

et al. 2010

View full text Add to dashboard Cite

We have studied a series of InAs/GaSb coupled quantum wells using magneto-infrared spectroscopy for high magnetic fields up to 33 T within temperatures ranging from 4 K to 45 K in both Faraday and tilted field geometries. This type of coupled quantum wells consists of an electron layer in the InAs quantum well and a hole layer in the GaSb quantum well, forming the so-called two dimensional electron-hole bilayer system. Unlike the samples studied in the past, the hybridization of the electron and hole subbands in our samples is largely reduced by having narrower wells and an AlSb barrier layer interposed between the InAs and the GaSb quantum wells, rendering them weakly hybridized. Previous studies have revealed multiple absorption modes near the electron cyclotron resonance of the InAs layer in moderately and strongly hybridized samples, while only a single absorption mode was observed in the weakly hybridized samples. We have observed a pair of absorption modes occurring only at magnetic fields higher than 14 T, which exhibited several interesting phenomena. Among which we found two unique types of behavior that distinguishes this work from the ones reported in the literature. This pair of modes is very robust against rising thermal excitations and increasing magnetic fields alligned parallel to the heterostructures. While the previous results were aptly explained by the antilevel crossing gap due to the hybridization of the electron and hole wavefunctions, i.e. conduction-valence Landau level mixing, the unique features reported in this paper cannot be explained within the same concept. The unusual properties found in this study and their connection to the known models for InAs/GaSb heterostructures will be disccused; in addition, several alternative ideas will be proposed in this paper and it appears that a spontaneous phase separation can account for most of the observed features.

show abstract

Section: Resultsmentioning

confidence: 75%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Magneto-infrared modes in InAs-AlSb-GaSb coupled quantum wells

et al. 2010

View full text Add to dashboard Cite

show abstract

“…Throughout this paper, the valence band offset (VBO, see Fig. 1) is fixed to 0.56 eV [44][45][46] and the energy zero is set at the top of the valence band of bulk InAs.…”

Section: Methodsmentioning

confidence: 99%

Band-inverted gaps in InAs/GaSb and GaSb/InAs core-shell nanowires

Luo

Huang

Liao

et al. 2016

Sci Rep

View full text Add to dashboard Cite

The [111]-oriented InAs/GaSb and GaSb/InAs core-shell nanowires have been studied by the 8 × 8 Luttinger-Kohn Hamiltonian to search for non-vanishing fundamental gaps between inverted electron and hole bands. We focus on the variations of the band-inverted fundamental gap, the hybridization gap, and the effective gap with the core radius and shell thickness of the nanowires. The evolutions of all the energy gaps with the structural parameters are shown to be dominantly governed by the effect of quantum confinement. With a fixed core radius, a band-inverted fundamental gap exists only at intermediate shell thicknesses. The maximum band-inverted gap found is ~4.4 meV for GaSb/InAs and ~3.5 meV for InAs/GaSb core-shell nanowires, and for the GaSb/InAs core-shell nanowires the gap persists over a wider range of geometrical parameters. The intrinsic reason for these differences between the two types of nanowires is that in the shell the electron-like states of InAs is more delocalized than the hole-like state of GaSb, while in the core the hole-like state of GaSb is more delocalized than the electron-like state of InAs, and both favor a stronger electron-hole hybridization.

show abstract

“…The band offset between the VBs of the two different materials is given by ∆E = 0.56 eV. [41][42][43] In the literature, a range of parameters extracted from experiments and first-principles calculations exist, and the parameters used in k · p simulations are, many times, altered to avoid spurious solutions.…”

Section: Acknowledgmentsmentioning

confidence: 99%

Extracting band structure characteristics of GaSb/InAs core-shell nanowires from thermoelectric properties

Viñas¹,

Xu²,

Leijnse³

2017

Phys. Rev. B

View full text Add to dashboard Cite

Nanowires with a GaSb core and an InAs shell (and the inverted structure) are interesting for studies of electron-hole hybridization and interaction effects due to the bulk broken band-gap alignment at the material interface. We have used eight-band k · p theory together with the envelope function approximation to calculate the band structure of such nanowires. For a fixed core radius, as a function of shell thickness the band structure changes from metallic (for a thick shell) to semiconducting (for a thin shell) with a gap induced by quantum confinement. For intermediate shell thickness, a different gapped band structure can appear, where the gap is induced by hybridization between the valence band in GaSb and the conduction band in InAs. To establish a relationship between the nanowire band structures and signatures in thermoelectrical measurements, we use the calculated energy dispersions as input to the Boltzmann equation and to ballistic transport equations to study the diffusive limit and the ballistic limit, respectively. Our theoretical results provide a guide for experiments, showing how thermoelectric measurements in a gated setup can be used to distinguish between different types of band gaps, or tune the system into a regime with few electrons and few holes, which can be of interest for studies of exciton physics.

show abstract

Pressure Dependence of Band Offsets in an InAs-GaSb Superlattice

Cited by 50 publications

References 20 publications

Magneto-infrared modes in InAs-AlSb-GaSb coupled quantum wells

Magneto-infrared modes in InAs-AlSb-GaSb coupled quantum wells

Band-inverted gaps in InAs/GaSb and GaSb/InAs core-shell nanowires

Extracting band structure characteristics of GaSb/InAs core-shell nanowires from thermoelectric properties

Contact Info

Product

Resources

About