Exciton dynamics studied via internal THz transitions

Terahertz Linear and Nonlinear Dynamics in Confined Magnetoexcitons

We have probed the linear and nonlinear terahertz (THz) properties of magnetoexcitons in GaAs/AlGaAs quantum wells. By monitoring photoluminescence from the quantum wells that were simultaneously driven by THz fields, we have directly observed internal transitions of excitons. In the nonlinear, high-THz-excitation regime, we observed mixing of optical and THz radiation, which resulted in THz op...

Picosecond dynamics of internal exciton transitions in CdSe nanorods

Probing Exciton States in Hybrid Perovskite Semiconductors

Hybrid Organic-Inorganic Perovskites are a new generation of photovoltaic semiconductors that do not use scarce metals. Study of the viability of these materials involves detailed understanding of the various states an electron may go through in the material. Exciton states are bound excited electronic states just below the conduction band where the electron is essentially orbiting the “hole,” ...

Terahertz Sideband Generation and Coherent Control in Semiconductor Microcavities

The controlled variation of the temperature, magnetic field, electrical bias, and quantum-well (QW) thickness [1] have all been employed to afford tunability of the exciton–cavity-photon coupling in semiconductor microcavities (MC’s). Time-dependent knobs, however, have attracted scant attention. As we show in this Letter, the modulation of the optical properties of a MC at THz frequencies may ...

Intrinsic optical bistability of thin films of linear molecular aggregates: the two-exciton approximation.

We generalize our recent work on the optical bistability of thin films of molecular aggregates [J. A. Klugkist et al., J. Chem. Phys. 127, 164705 (2007)] by accounting for the optical transitions from the one-exciton manifold to the two-exciton manifold as well as the exciton-exciton annihilation of the two-exciton states via a high-lying molecular vibronic term. We also include the relaxation ...