arXiv:1808.07544 · Physical Review A

Pulse engineering for population control under dephasing and dissipation

Ivan Medina, F. L. Semião

Published Jul 2, 2019• 31 citations

Abstract

We apply reverse engineering to find electromagnetic pulses that allow for the control of populations in quantum systems under dephasing and thermal noises. In particular, we discuss two-level systems given their importance in the description of several molecular systems as well as quantum computing. Such an investigation naturally finds applications in a multitude of physical situations involving the control of quantum systems. We present an analytical description of the pulse which solves a constrained dynamics where the initial and final populations are fixed a priori. This constrained dynamics is sometimes impossible, and we precisely spot the conditions for that. One of our results is the presentation of analytical conditions for the establishment of steady states for finite coherence in the presence of noise. This might naturally find applications in quantum memories.

DOI: 10.1103/physreva.100.012103

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