Abstract
Paul Eastham (Trinity College Dublin, Ireland)
Adiabatic control of many-particle states in coupled quantum dots
In collaboration with R. T. Brierley, C. Creatore, R. T. Phillips, P. B. Littlewood, University of Cambridge.
Precise control of the state of a quantum system is fundamental to
establishing methods of quantum information processing and studying
quantum dynamics. Excitons in semiconductor quantum dots are of
particular interest, since their coupling to light allows them to be
driven into particular states using laser pulses, and provides a
controllable interaction between them. While excitons are usually
created using incoherent excitation or precisely timed resonant pulses
(Rabi pulses), neither technique allow the creation of controlled
states in systems of many dots. Excitation with chirped laser pulses,
however, has been shown both theoretically [1] and experimentally [2]
to allow the creation of single excitons in quantum dots. Here I
consider the extension of this approach to the creation of more exotic
states in many-particle systems. I outline how it can be generalized
to generate entangled states in ensembles of pairwise-coupled quantum
dots. I also demonstrate how it can be used to populate specific
states in generic models models of interacting few-level systems such
as quantum dots, in particular one-dimensional and mean-field spin
models.
[1] P. R. Eastham and R. T. Phillips, Phys. Rev. B 79, 165303 (2009);
E. R. Schmigdall, P. R. Eastham, and R. T. Phillips, Phys. Rev. B. 81,
195306 (2010)
[2] Y. Wu, I. M. Piper, M. Ediger, P. Brereton, E. R. Schmigdall,
P. R. Eastham, M. Hugues, M. Hopkinson and R. T. Phillips,
Phys. Rev. Lett. 106, 067401 (2011)