Related papers: Optimized Steering: Quantum State Engineering and Exceptional Points

Optimized Steering: Quantum State Engineering and Exceptional Points

URL: http://arxiv.org/abs/2101.07284v4
Date: Tue, 18 Jan 2022 17:32:56 GMT
Title: Optimized Steering: Quantum State Engineering and Exceptional Points
Authors: Parveen Kumar, Kyrylo Snizhko, Yuval Gefen, and Bernd Rosenow
Abstract summary: We analyze the steering of a two-level system using the interplay of a system Hamiltonian and weak measurements. We show that the optimization of such a steering protocol is underlain by the presence of Liouvillian exceptional points.
Score: 1.4174475093445233
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Abstract: The state of a quantum system may be steered towards a predesignated target state, employing a sequence of weak $\textit{blind}$ measurements (where the detector's readouts are traced out). Here we analyze the steering of a two-level system using the interplay of a system Hamiltonian and weak measurements, and show that $\textit{any}$ pure or mixed state can be targeted. We show that the optimization of such a steering protocol is underlain by the presence of Liouvillian exceptional points. More specifically, for high purity target states, optimal steering implies purely relaxational dynamics marked by a second-order exceptional point, while for low purity target states, it implies an oscillatory approach to the target state. The dynamical phase transition between these two regimes is characterized by a third-order exceptional point.

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