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

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.