Optimal control of quantum rings by terahertz laser pulses

E. Räsänen*, A. Castro, J. Werschnik, A. Rubio, E. K.U. Gross

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

98 Scopus citations


Complete control of single-electron states in a two-dimensional semiconductor quantum-ring model is established, opening a path into coherent laser-driven single-gate qubits. The control scheme is developed in the framework of optimal-control theory for laser pulses of two-component polarization. In terms of pulse lengths and target-state occupations, the scheme is shown to be superior to conventional control methods that exploit Rabi oscillations generated by uniform circularly polarized pulses. Current-carrying states in a quantum ring can be used to manipulate a two-level subsystem at the ring center. Combining our results, we propose a realistic approach to construct a laser-driven single-gate qubit that has switching times in the terahertz regime.

Original languageAmerican English
Article number157404
JournalPhysical Review Letters
Issue number15
StatePublished - 13 Apr 2007
Externally publishedYes


Dive into the research topics of 'Optimal control of quantum rings by terahertz laser pulses'. Together they form a unique fingerprint.

Cite this