Cyclotron and combined phonon-assisted resonances in double-well heterostructure In$_{0.65}$Ga$_{0.35}$As/In$_{0.52}$Al$_{0.48}$As at megagauss magnetic fields

TL;DR

This study reports the observation of new phonon-assisted cyclotron and combined resonances in InGaAs/InAlAs double quantum wells under megagauss magnetic fields, explained by an advanced eight-band $ extbf{k} extbf{ extperiodcentered} extbf{p}$ model.

Contribution

First observation of phonon-assisted cyclotron and combined resonances in double quantum wells at megagauss fields, supported by a detailed theoretical model.

Findings

Detection of new phonon-assisted resonances.

Agreement of experimental data with the eight-band $ extbf{k} extbf{ extperiodcentered} extbf{p}$ model.

High magnetic fields enable new resonance phenomena.

Abstract

Experiments on resonances of conduction electrons in InGaAs/InAlAs double quantum wells at megagauss magnetic fields in the Faraday geometry are reported. We observe new cyclotron resonances assisted by emission of InAs-like and GaAs-like optic phonons and a combined (cyclotron-spin) resonance assisted by emission of InAs-like phonon. The observations are very well described for three laser frequencies with the use of an eight-band (three level) $\textbf{k}\cdot \textbf{p}$ model, taking into account position- and energy-dependent effective masses and spin g-factors. It is indicated that the new observations are possible due to the application very high magnetic fields.