Energy storage and coherence in closed and open quantum batteries

Abstract

We study the role of coherence in closed and open quantum batteries. We obtain upper bounds to the work performed or energy exchanged by both closed and open quantum batteries in terms of coherence. Specifically, we show that the energy storage can be bounded by the Hilbert-Schmidt coherence of the density matrix in the spectral basis of the unitary operator that encodes the evolution of the battery. We also show that an analogous bound can be obtained in terms of the battery's Hamiltonian coherence in the basis of the unitary operator by evaluating their commutator. We apply these bounds to a 4-state quantum system and the anisotropic XY Ising model in the closed system case, and the Spin-Boson model in the open case.

Enhancing coherent energy transfer between quantum devices via a mediator

“…[17], various theoretical proposals have been elaborated with the aim of realizing miniaturized devices able to exploit genuine quantum features to store and release energy in a controlled way. They can be implemented in set-ups conventionally used for quantum computation [18,19], in artificial atoms [20][21][22][23][24][25][26][27][28][29][30][31] and in the framework of cavity and circuit quantum electrodynamics [32][33][34][35][36]. These theoretical investigations represent a change of paradigm in the field of energy storage with respect to two centuries old electrochemical principles which are still at the core of nowadays technology.…”

Incoherent control of two-photon induced optical measurements in open quantum systems: quantum heat engine perspective

“…The ascent of quantum heat engines (QHEs) attracted a significant amount of attention in the last few decades and constitutes an important research direction within the quantum thermodynamics, both theoretically [5][6][7][8][9][10][11][12][13] and experimentally [14][15][16][17][18][19]. In addition to the diverse development of QHEs [20][21][22], it has intrinsic relationship with the real physical systems such as laser, solar cell [23,24], battery [25,26], light harvesting [27], etc. While some of the promising features of QHEs such as quantum coherence and entanglement [28][29][30][31] show a possibility for enhancing the maximum output power for resonantly driven systems [32], the significance of entanglement in optical measurements in open quantum systems from the QHE perspective has not been investigated so far.…”

Quantum battery in nonequilibrium reservoirs

“…Ever since the concept of quantum battery was proposed by Alicke and Fannes [1], several quantum battery models have been put forward in different physical systems, for example, the spin or resonator chain model [2][3][4][5][6][7][8][9][10][11][12][13][14][15], the Tavis-Cummings and Dicke model in quantum optics [16][17][18][19][20][21], Rydberg atom system [22]. In some of these systems, the Floquent technology has been used to enhance the performance of the quantum battery [23][24][25].…”