Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:2008.09327 · Quantum

Multi-spin counter-diabatic driving in many-body quantum Otto refrigerators

Andreas Hartmann, Victor Mukherjee, Glen Bigan Mbeng, Wolfgang Niedenzu, Wolfgang Lechner

Published Dec 24, 2020• 20 citations
arXivHTMLPDF

Abstract

Quantum refrigerators pump heat from a cold to a hot reservoir. In the few-particle regime, counter-diabatic (CD) driving of, originally adiabatic, work-exchange strokes is a promising candidate to overcome the bottleneck of vanishing cooling power. Here, we present a finite-time many-body quantum refrigerator that yields finite cooling power at high coefficient of performance, that considerably outperforms its non-adiabatic counterpart. We employ multi-spin CD driving and numerically investigate the scaling behavior of the refrigeration performance with system size. We further prove that optimal refrigeration via the exact CD protocol is a catalytic process.

DOI
10.22331/q-2020-12-24-377

Related papers

Shortcut-to-adiabaticity quantum Otto refrigerator

Obinna Abah, M Paternostro, E Lutz

We investigate the performance of a quantum Otto refrigerator operating in finite time and exploiting local counterdiabatic techniques. We evaluate its coefficient of performance and cooling power when the working medium consists of a quantum harmonic oscillator with a time-dependent frequency. We find that the quantum refrigerator outperforms its conventional counterpart, except for very short cycle times, even when the driving cost of the local counterdiabatic driving is included. We moreover derive upper bounds on the performance of the thermal machine based on quantum speed limits and show that they are tighter than the second law of thermodynamics.

•May 4, 2020•0 citations

Many-body quantum heat engines with shortcuts to adiabaticity

Andreas Hartmann, Victor Mukherjee, Wolfgang Niedenzu +1 more

The authors propose a many-body quantum heat engine (QHE) that efficiently operates at finite power. Due to the adiabatic theorem, efficient QHEs generally yield a vanishing power output. The method of shortcuts to adiabaticity is a promising candidate to overcome this bottleneck, but usually requires a-priori knowledge of the system's eigenstates at all times and is thus hard to implement for many-body systems. Here, the authors apply approximate local counter-diabatic protocols that are applicable in state-of-the-art experiments.

arXiv:1912.08689•Physical Review Research•May 8, 2020•67 citations

Optimal performance of a quantum Otto refrigerator

Obinna Abah, Eric Lutz

We consider a quantum Otto refrigerator cycle of a time-dependent harmonic oscillator. We investigate the coefficient of performance at maximum figure of merit for adiabatic and nonadiabatic frequency modulations. We obtain analytical expressions for the optimal performance both in the high-temperature (classical) regime and in the low-temperature (quantum) limit. We moreover analyze the breakdown of the cooling cycle for strongly nonadiabatic driving protocols and derive analytical estimates for the minimal driving time allowed for cooling.

arXiv:1601.04303•Europhysics Letters (EPL)•Mar 1, 2016•90 citations

Unlocking inaccessible performance of the quantum refrigerator with catalysts

Cong Fu, Ousi Pan, Zhiqiang Fan +4 more

Quantum thermal machines offer promising platforms for exploring the fundamental limits of thermodynamics at the microscopic scale. Building on majorization theory, we further extend the catalytic concept to a two-stroke quantum refrigerator via discrete strokes. The working medium consists of two two-level systems and two heat reservoirs at different temperatures and is assisted by an auxiliary system acting as a catalyst. We show that the presence of the catalyst leads to two significant enhancements: it enables the coefficient of performance and the cooling capacity to exceed the Otto bound and allows the refrigerator to operate in frequency and temperature regimes that are inaccessible without a catalyst. These results highlight the potential of catalytic mechanisms to broaden the operational capabilities of quantum thermal devices and to surpass conventional thermodynamic performance limits.

arXiv:2507.12016•Applied Physics Letters•Jan 19, 2026•1 citation

Shortcut-to-adiabaticity quantum tripartite Otto cycle

Lunan Li, Hai Li, Wen-Li Yu +3 more

Abstract For an Otto cycle there always exists a trade-off between the cycle efficiency and the output power due to the requirement of cycle length. The shortcut to adiabatic (STA) technology provides an effective way to deal with the difficulty of zero-output power in conventional Otto cycle. In this paper, the Otto cycle of three-qubit system as the working substance with counterdiabatic driving has been investigated. It is demonstrated that the tripartite Otto cycle as a universal machine, in the suitable regimes of external control parameter, could work as a quantum heat engine (QHE), refrigerator or heat pump. And, the performances of QHE and refrigerator with and without STA, such as the power and efficiency of QHE and the coefficient of performance (COP) and figure of merit (FOM) of refrigerator, have been investigated. It shows the application of STA scheme can lead to an effective enhancement in the performances of Otto cycle, including achievements of a high QHE’s/refrigerator’s power associated with a moderate QHE’s efficiency/COP of refrigerator. Especially, it is interesting that even in a short-time cycle the optimization of control parameters could arise a remarkable improvement in the efficiency (or COP) of STA QHE (refrigerator), approaching the ideal efficiency or COP of conventional Otto cycle with quasi-static process. Finally, with the aid of parameter optimization the trade-off regions between the efficiency and the power (the COP and the FOM) of STA Otto engine (refrigerator) have been advised.

Journal of Physics B Atomic Molecular and Optical Physics•Nov 3, 2021•8 citations

Otto refrigerator based on a superconducting qubit: Classical and quantum performance

Bayan Karimi, Jukka P Pekola

Experimental demonstration of a truly quantum mechanical solid-state heat engine or refrigerator remains elusive up to now. Here, a four-stroke quantum refrigerator that can be realized using a superconducting qubit coupled alternately to two resonators with embedded reservoirs is analyzed theoretically. Besides being a practically feasible thermal machine, this concept presents a number of fundamentally interesting features. At high frequencies, the system exhibits nearly coherent dynamics, leading to quantum oscillations in cooling power versus operation frequency. At intermediate frequencies, an ideal Otto cycle can be realized. In the nearly adiabatic regime, the cooling power is quadratic in frequency and can be separated to classical and quantum contributions. Interestingly, it is shown here that quantum coherence leads always to performance that is inferior as compared to that arising from purely classical dynamics. Furthermore, in the nearly adiabatic regime the efficiency of the refrigerator exceeds clearly that of the standard Otto cycle.

arXiv:1610.02776•Physical review. B./Physical review. B•Nov 9, 2016•150 citations
Quantum refrigerators pump heat from a cold to a hot reservoir. In the few-particle regime, counter-diabatic (CD) driving of, originally adiabatic, work-exchange strokes is a promising candidate to overcome the bottleneck of vanishing cooling power. Here, we present a finite-time many-body quantum refrigerator that yields finite cooling power at high coefficient of performance, that considerably outperforms its non-adiabatic counterpart. We employ multi-spin CD driving and numerically investigate the scaling behavior of the refrigeration performance with system size. We further prove that optimal refrigeration via the exact CD protocol is a catalytic process.
We investigate the performance of a quantum Otto refrigerator operating in finite time and exploiting local counterdiabatic techniques. We evaluate its coefficient of performance and cooling power when the working medium consists of a quantum harmonic oscillator with a time-dependent frequency. We find that the quantum refrigerator outperforms its conventional counterpart, except for very short cycle times, even when the driving cost of the local counterdiabatic driving is included. We moreover derive upper bounds on the performance of the thermal machine based on quantum speed limits and show that they are tighter than the second law of thermodynamics.
The authors propose a many-body quantum heat engine (QHE) that efficiently operates at finite power. Due to the adiabatic theorem, efficient QHEs generally yield a vanishing power output. The method of shortcuts to adiabaticity is a promising candidate to overcome this bottleneck, but usually requires a-priori knowledge of the system's eigenstates at all times and is thus hard to implement for many-body systems. Here, the authors apply approximate local counter-diabatic protocols that are applicable in state-of-the-art experiments.
We consider a quantum Otto refrigerator cycle of a time-dependent harmonic oscillator. We investigate the coefficient of performance at maximum figure of merit for adiabatic and nonadiabatic frequency modulations. We obtain analytical expressions for the optimal performance both in the high-temperature (classical) regime and in the low-temperature (quantum) limit. We moreover analyze the breakdown of the cooling cycle for strongly nonadiabatic driving protocols and derive analytical estimates for the minimal driving time allowed for cooling.
Quantum thermal machines offer promising platforms for exploring the fundamental limits of thermodynamics at the microscopic scale. Building on majorization theory, we further extend the catalytic concept to a two-stroke quantum refrigerator via discrete strokes. The working medium consists of two two-level systems and two heat reservoirs at different temperatures and is assisted by an auxiliary system acting as a catalyst. We show that the presence of the catalyst leads to two significant enhancements: it enables the coefficient of performance and the cooling capacity to exceed the Otto bound and allows the refrigerator to operate in frequency and temperature regimes that are inaccessible without a catalyst. These results highlight the potential of catalytic mechanisms to broaden the operational capabilities of quantum thermal devices and to surpass conventional thermodynamic performance limits.
Abstract For an Otto cycle there always exists a trade-off between the cycle efficiency and the output power due to the requirement of cycle length. The shortcut to adiabatic (STA) technology provides an effective way to deal with the difficulty of zero-output power in conventional Otto cycle. In this paper, the Otto cycle of three-qubit system as the working substance with counterdiabatic driving has been investigated. It is demonstrated that the tripartite Otto cycle as a universal machine, in the suitable regimes of external control parameter, could work as a quantum heat engine (QHE), refrigerator or heat pump. And, the performances of QHE and refrigerator with and without STA, such as the power and efficiency of QHE and the coefficient of performance (COP) and figure of merit (FOM) of refrigerator, have been investigated. It shows the application of STA scheme can lead to an effective enhancement in the performances of Otto cycle, including achievements of a high QHE’s/refrigerator’s power associated with a moderate QHE’s efficiency/COP of refrigerator. Especially, it is interesting that even in a short-time cycle the optimization of control parameters could arise a remarkable improvement in the efficiency (or COP) of STA QHE (refrigerator), approaching the ideal efficiency or COP of conventional Otto cycle with quasi-static process. Finally, with the aid of parameter optimization the trade-off regions between the efficiency and the power (the COP and the FOM) of STA Otto engine (refrigerator) have been advised.
Experimental demonstration of a truly quantum mechanical solid-state heat engine or refrigerator remains elusive up to now. Here, a four-stroke quantum refrigerator that can be realized using a superconducting qubit coupled alternately to two resonators with embedded reservoirs is analyzed theoretically. Besides being a practically feasible thermal machine, this concept presents a number of fundamentally interesting features. At high frequencies, the system exhibits nearly coherent dynamics, leading to quantum oscillations in cooling power versus operation frequency. At intermediate frequencies, an ideal Otto cycle can be realized. In the nearly adiabatic regime, the cooling power is quadratic in frequency and can be separated to classical and quantum contributions. Interestingly, it is shown here that quantum coherence leads always to performance that is inferior as compared to that arising from purely classical dynamics. Furthermore, in the nearly adiabatic regime the efficiency of the refrigerator exceeds clearly that of the standard Otto cycle.