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arXiv · 1410.7106

Classical-driving-assisted quantum speed-up

Ying-Jie Zhang·Wei Han·Yun-Jie Xia·Jun-Peng Cao·Heng Fan
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Abstract

We propose a method of accelerating the speed of evolution of an open system by an external classical driving field for a qubit in a zero-temperature structured reservoir. It is shown that, with a judicious choice of the driving strength of the applied classical field, a speed-up evolution of an open system can be achieved in both the weak system-environment couplings and the strong system-environment couplings. By considering the relationship between non-Makovianity of environment and the classical field, we can drive the open system from the Markovian to the non-Markovian regime by manipulating the driving strength of classical field. That is the intrinsic physical reason that the classical field may induce the speed-up process. In addition, the roles of this classical field on the variation of quantum evolution speed in the whole decoherence process is discussed.

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Ying-Jie Zhang, Wei Han, Yun-Jie Xia, Jun-Peng Cao, Heng Fan. 2014-11-28. Classical-driving-assisted quantum speed-up. https://doi.org/10.1103/physreva.91.032112

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