ac-field–modulated terahertz radiation based on dipolaritons
1 School of Physics, Peking University - Beijing 100871, China
2 Institute of Applied Physics and Computational Mathematics - P. O. Box 8009(28), Beijing 100088, China
Received: 10 October 2014
Accepted: 4 December 2014
Terahertz (THz) emission based on dipolaritons, quasiparticles formed by the direct exciton, indirect exciton and photon, in semiconductor double quantum wells embedded in microcavities is a novel approach for THz wave generation due to their large dipole moment. We propose an effective and convenient way of modulating such THz emission by using dc and ac fields to adjust the coherent tunneling between quantum wells. With the help of resonant tunneling and photon-assisted transport mechanisms, efficient THz radiation (with tunable frequency and appreciable radiation power) can be obtained by optimizing the external dc and ac fields. We have found dark Floquet states, which can be used to quench the radiation and prepare pure indirect exciton state.
PACS: 71.36.+c – Polaritons (including photon-phonon and photon-magnon interactions) / 71.35.-y – Excitons and related phenomena / 73.21.Fg – Quantum wells
© EPLA, 2014