Regular Article

Driving the quantum speed limit of a central spin model by pulse control

¹ Department of Information Engineering, Changzhou Vocational Institute of Light Industry, Changzhou 213164, P.R. China
² School of Physics, Beijing Institute of Technology, Beijing 100081, P.R. China

^a e-mail: hlukaoyan@163.com

Received: 14 March 2018
Received in final form: 7 May 2018
Published online: 5 July 2018

Abstract

We investigate the quantum speed limit (QSL) time of the central qubit coupled with a thermodynamic Ising spin chain. The external bang–bang (BB) pulse control is applied on the model. We show that the evolution speed of the central system can be enhanced by the BB pulse. Meanwhile, the influence from magnetic field and temperature of bath are also studied, and we find that for the situation of strong external field or low temperature the evolution speed of system can be accelerated. Besides these, the function of the sizes of environment is exhibited in our work and we discover the effect from the qubits numbers of bath on QSL time depends on the coupling strength between central system and bath spins.