Time-optimal control of quantum state preparation and entanglement
creation in two-qubit quantum system with bounded amplitude
- URL: http://arxiv.org/abs/2211.09323v1
- Date: Thu, 17 Nov 2022 03:55:50 GMT
- Title: Time-optimal control of quantum state preparation and entanglement
creation in two-qubit quantum system with bounded amplitude
- Authors: Xikun Li
- Abstract summary: We study the time-optimal control problem in a two-qubit system with bounded amplitude.
Two problems are considered: quantum state preparation and entanglement creation.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We study the time-optimal control problem in a two-qubit system with bounded
amplitude. Two problems are considered: quantum state preparation and
entanglement creation. Cost functions, fidelity and concurrence, are optimized
over bang-off controls for various values of the total duration. For quantum
state preparation problem, three critical time points are determined with high
precision, and optimal controls are obtained for different durations. A better
estimation of the quantum speed limit is obtained, so is the time-optimal
control. For entanglement creation problem, two critical time points are
determined, and the type of optimal controls found is found to be of special
type. In addition, from the numerical results we conjecture that unit
concurrence might be reached by infinite time-optimal controls with the same
minimal duration.
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