Controlling Quantum Condensed Matter With Light

Margaret M. Murnane, Jun Ye

Controlling coherent light across a vast spectral range enables ultraprecise measurements and the quantum control of atomic, molecular, and condensed-matter systems.

Hermann Uys, Ismail Yunus Akhalwaya, N Botha +8 more

David W. Chandler

Mirco Kolarczik, Nina Owschimikow, Julian Korn +6 more

Coherence in light–matter interaction is a necessary ingredient if light is used to control the quantum state of a material system. Coherent effects are firmly associated with isolated systems kept at low temperature. The exceedingly fast dephasing in condensed matter environments, in particular at elevated temperatures, may well erase all coherent information in the material at timescales shorter than a laser excitation pulse. Here we show for an ensemble of semiconductor quantum dots that even in the presence of ultrafast dephasing, for suitably designed condensed matter systems quantum-coherent effects are robust enough to be observable at room temperature. Our conclusions are based on an analysis of the reshaping an ultrafast laser pulse undergoes on propagation through a semiconductor quantum dot amplifier. We show that this pulse modification contains the signature of coherent light–matter interaction and can be controlled by adjusting the population of the quantum dots via electrical injection. Quantum coherence effects are often only visible at low temperatures, where dephasing times are not too short. Here Kolarczik et al. show that quantum coherence effects can appear in the reshaping of ultrafast laser pulses passing through quantum dots even at room temperature.

Yaron R. Silberberg

Photons propagate in periodic and disordered lattices with minimal decoherence and with great control of initial states, displaying a rich spectrum of new phenomena and throwing light on a number of condensed matter effects.

Bertrand I. Halperin, Subir Sachdev A, Nathan Goldman +1 more