Temperature-dependent cyclotron resonance in a hybridized electron–hole system in InAs/GaSb heterostructures

Abstract

Cyclotron resonance measurements are performed as a function of temperature on InAs/GaSb quantum well structures. The effects of electron-hole hybridization on cyclotron resonance are found to be strongly temperature dependent. As the temperature increases, the cyclotron resonance spectra narrow dramatically and multiple splittings due to electron-hole hybridizations disappear. This phenomenon is believed to be due to the classical Coulomb interaction between electrons with different cyclotron effective masses. The influence of the minigap formed due to electron-hole coupling is shown to be particularly important in narrower gap structures where strong thermal excitation of carriers is observed across the minigap. The influence of the minigap on the system is confirmed by the application of large parallel magnetic fields which decouple the electron and hole bands.

Partial hybridisation of electron-hole states in an InAs/GaSb double quantum well heterostructure

“…The effective mass of 0.070 m0 determined from the Dingle plots is significantly different to the accepted value for InAs 2DEGs (0.032 m0-0.046 m0) 20,21,22,23 , and so we attribute the majority transport in this structure to hybridised electron-hole states. Additionally, this effective mass aligns extremely well with the mean of the effective masses of electrons in…”

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

“…79 Upon taking a closer look at the data in the literature, the separation between the modes is indeed increasing with increasing magnetic field defined piecewise between the crossing points of the electron and hole LLs. 87,88 Since the region between two crossings expands with increasing magnetic field (see Fig. 3), a magnetic-field dependent separation will be more pronounced at high magnetic fields.…”

“…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.…”

Subband transitions in dual-band n-B-n InAs/GaSb superlattice infrared photodetector identified by photoresponse spectra

“…2͑a͒ clearly exhibits two distinctive peaks that may be related to the transitions from the first heavy-and light-hole ͑HH1 and LH1͒ subbands to the conduction ͑C͒ one in the MW-SLS. [8][9][10][11][12][13] On the other hand, the PL measurement reveals a single peak that lies just at the absorption edge of each PR spectrum, which is associated with the C-HH1 emission.…”

“…6 The n-B-n InAs/ GaSb SLIP has already been proven to operate at a wavelength of about 8 m. 7 A thermal imager was also demonstrated by using ͓320ϫ 256͔ focal-plane-array SLIP with a cutoff wavelength of 4.2 m at a detector temperature of 77 K. 8 Owing to remarkable progress in the growth technology, the number of reports on the device achievement of InAs/ GaSb SLS has rapidly increased. [9][10][11][12][13] However, uncertainty still exists in understanding absorption and emission features of SLIPs because of diversity of SLS structures, 11,14 and the PR band selectivity in the dual-band n-B-n SLIP is a little ambiguous. In this letter, the subband transitions in MW-and LW-SLS are investigated by PR spectra and photoluminescence ͑PL͒ profiles.…”