Quantum Energy Lines and the Optimal Output Ergotropy Problem

Materials and devices for fundamental quantum science and quantum technologies

“…Indeed, it is difficult to imagine a "quantum society" where computing, communications, and sensing will be carried out by relying on the principles of quantum mechanical laws while energy will be provided by systems ruled by standard electrochemical laws and 200-years old designs. There are three classes of energy-related quantum devices, which are currently being mainly studied by academia and that will need to gradually be evaluated and adopted by industry: i) quantum heat engines for energy production [187][188][189][190][191][192][193][194], ii) quantum batteries [195][196][197][198][199][200][201][202][203][204][205] and supercapacitors [206] for energy storage, and iii) quantum energy lines [207] for energy transfer. Research and development on all these aspects may lead to a profound "cultural" and technological revolution in how energy is produced, stored, and conveyed.…”

Quantum advantage in charging cavity and spin batteries by repeated interactions

“…In such collective processes, the role of dissipation [46][47][48][49][50][51][52], many-body interactions [44,[53][54][55][56][57][58][59][60][61][62][63], and energy fluctuations [64][65][66][67][68][69][70] has also been investigated. In parallel, various types of quantum systems have been considered as quantum batteries, ranging from qubit ensembles [42,[71][72][73][74][75][76][77][78] and ladder models [67,[79][80][81][82][83][84] to oscillators and flywheels [50,[85][86][87][88]. One of the prime candidates for experimental proofs-of-principle is the Dicke-model battery [71]…”

Quantum Work Capacitances

“…A similar endeavour was tackled in Ref. [22,23] and mimics the optimization problem one faces in quantum communication [24][25][26][27][28][29] when designing information encoding strategies that are capable of mitigating the detrimental effects of dissipation and decoherence.…”

“…As in [22,23] we leverage on a series of functionals which, depending on the resources that we're allowed to exploit for the task, have been introduced in the literature to quantify the maximum amount of useful energy (work) one can extract from a given state of a quantum system [30]. The simplest, most widely studied of these quantities is the ergotropy functional [31] which represents the maximum mean value of the extractable energy one can get from closed models where the only allowed operations are modulations of the system Hamiltonian (no interactions with external elements being allowed).…”