209 citations · 632 across the 8 of their papers we have counts for
8 papers
Probing Bose-Einstein Condensation of Excitons with Electromagnetic Radiation
K. Johnsen, G. M. Kavoulakis
We examine the absorption spectrum of electromagnetic radiation from excitons, where an exciton in the state absorbs a photon and makes a transition to the state. We demo…
Spin-dynamic field coupling in strongly THz driven semiconductors : local inversion symmetry breaking
Kristinn Johnsen
We study theoretically the optics in undoped direct gap semiconductors which are strongly driven in the THz regime. We calculate the optical sideband generation due to nonlinear mi…
Contact resistance of quantum tubes
Niels Asger Mortensen, Kristinn Johnsen, Antti-Pekka Jauho +1
We consider the conductance of a quantum tube connected to a metallic contact. The number of angular momentum states that the tube can support depends on the strength of the radial…
Quasienergy Spectroscopy of Excitons
Kristinn Johnsen, Antti-Pekka Jauho
We theoretically study nonlinear optics of excitons under intense THz irradiation. In particular, the linear near infrared absorption and resonantly enhanced nonlinear sideband gen…
Excitonic Dynamical Franz-Keldysh Effect
K. B. Nordstrom, K. Johnsen, S. J. Allen +6
The Dynamical Franz-Keldysh Effect is exposed by exploring near-bandgap absorption in the presence of intense THz electric fields. It bridges the gap between the DC Franz- Keldysh…
Linear optical absorption spectra of mesoscopic structures in intense THz fields: free particle properties
Kristinn Johnsen, Antti-Pekka Jauho
We theoretically study the effect of THz radiation on the linear optical absorption spectra of semiconductor structures. A general theoretical framework, based on non-equilibrium G…