Institut für Theoretische Physik, Universität Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen, Germany.
Phys Rev Lett. 2013 Dec 27;111(26):260501. doi: 10.1103/PhysRevLett.111.260501.
A remarkably simple result is derived for the minimal time Tmin 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.
一个非常简单的结果被推导出来，用于通过 Landau-Zener 型哈密顿量或等效的时变激光驱动将一般初始态驱动到最终目标态所需的最小时间 Tmin。同时还推导出了相关的协议。当相互作用强度受到常数 c 的限制时，对于某些状态会出现一个惊喜。然后，对于大的 c，最优驱动是 bang-off-bang 型的，随着 c 的增加，就可以恢复到无约束的结果。然而，对于较小的 c，最优驱动可能会突然切换为 bang-bang 型。我们讨论了量子速度限制时间的概念。
