Efficiency of quantum controlled non-Markovian thermalization

• Published in: New journal of physics Vol. 17; no. 6; pp. 63031 - 63040
• Main Authors: Mukherjee, V, Giovannetti, V, Fazio, R, Huelga, S F, Calarco, T, Montangero, S
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 23.06.2015
• Subjects: Damping; Markov analysis; non-Markovian dynamics; open quantum systems; Optimal control; optimal control of quantum systems; Optimization; Physics; quantum speed limit; Quantum theory; Qubits (quantum computing); Thermalization (energy absorption)
• ISSN: 1367-2630; 1367-2630
• DOI: 10.1088/1367-2630/17/6/063031

We study optimal control strategies to optimize the relaxation rate towards the fixed point of a quantum system in the presence of a non-Markovian (NM) dissipative bath. Contrary to naive expectations that suggest that memory effects might be exploited to improve optimal control effectiveness, NM effects influence the optimal strategy in a non trivial way: we present a necessary condition to be satisfied so that the effectiveness of optimal control is enhanced by NM subject to suitable unitary controls. For illustration, we specialize our findings for the case of the dynamics of single qubit amplitude damping channels. The optimal control strategy presented here can be used to implement optimal cooling processes in quantum technologies and may have implications in quantum thermodynamics when assessing the efficiency of thermal micro-machines.