Driving at the Quantum Speed Limit: Optimal Control of a Two-Level System

作者:Hegerfeldt Gerhard C*
来源:Physical Review Letters, 2013, 111(26): 260501.
DOI:10.1103/PhysRevLett.111.260501

摘要

A remarkably simple result is derived for the minimal time T-min required to drive a general initial state to a final target state by a Landau-Zener-type Hamiltonian or, equivalently, by time-dependent laser driving. The associated protocol is also derived. A surprise arises for some states when the interaction strength is bounded by a constant c. Then, for large c, the optimal driving is of type bang-off-bang and for increasing c one recovers the unconstrained result. However, for smaller c the optimal driving can suddenly switch to bang-bang type. We discuss the notion of quantum speed limit time.

  • 出版日期2013-12-27