Quantum heat engine with long-range advantages

Abstract

The employment of long-range interactions in quantum devices provides a promising route towards enhancing their performance in quantum technology applications. Here, the presence of long-range interactions is shown to enhance the performances of a quantum heat engine featuring a many-body working substance. We focus on the paradigmatic example of a Kitaev chain undergoing a quantum Otto cycle and show that a substantial thermodynamic advantage may be achieved as the range of the interactions among its constituents increases. Interestingly, such an advantage is most significant for the realistic situation of a finite time cycle: the presence of long-range interactions reduces the non-adiabatic energy losses, by suppressing the detrimental effects of dynamically generated excitations. This effect allows mitigating the trade-off between power and efficiency, paving the way for a wide range of experimental and technological applications.

Logarithmic, fractal and volume-law entanglement in a Kitaev chain with long-range hopping and pairing

“…For the future, we intend to investigate these issues by performing quantum simulations of the model on actual quantum computers. This demands a careful engineering of the artificial non-local couplings on local quantum devices, a task which we are currently tackling on IBM Quantum devices [103].…”

“…An example of the rigidity of long-range interacting platforms against external drivings and of its utility for quantum technological applications is the possibility for such systems to host clean discrete Floquet time crystal phases [4][5][6][7]. Another example is the recently introduced advantage in the finite time performance of quantum heat-engines with a working substance hosting longrange couplings [8]. Moreover, this technological and theoretical interest is also supported from the experimental side by the possibility to implement long-range interacting systems in typical quantum simulation platforms, such as atomic molecular and optical (AMO) systems [9][10][11][12][13].…”

Many-body enhancement in a spin-chain quantum heat engine

“…The efficiency enhancement is largest for long-range interactions, which suppress occupation of energy levels beyond the first excited state. A performance enhancement due to long-range interactions has also been identified in Kitaev chains [92,93]. For diabatic engine operation, quantum friction degrades performance.…”

Spin-chain based quantum thermal machines

“…References [31,32] studied the case where the driven working fluid is a spin chain, and focussed on the possible impact of phase transitions on the engine performance. In the present paper we focus on a special type of models where the working fluid is represented by a many-body quantum system that is driven by a periodic sequence of operations (strokes) that either put it in thermal contact with one of the bath, or let it freely evolve under the action of its (local) Hamiltonian, that is, at variance with previous studies, e.g.…”

“…In the present paper we focus on a special type of models where the working fluid is represented by a many-body quantum system that is driven by a periodic sequence of operations (strokes) that either put it in thermal contact with one of the bath, or let it freely evolve under the action of its (local) Hamiltonian, that is, at variance with previous studies, e.g. [31,32], here the working fluid is not driven by external forces, except for turning on and off local couplings. In this setting, exploiting the quantum channel formalism [33], we show the emergence of limit cycles that force the system into out-of-equilibrium, metastable configurations characterized by oscillatory behaviours which depend on the details of the system Hamiltonain.…”