Minimal two-body quantum absorption refrigerator

Journal Article · 22 August 2021 · Physical Review. B

DOI: https://doi.org/10.1103/physrevb.104.075442 · OSTI ID:1852441

Bhandari, Bibek  ^[1]; Jordan, Andrew N. ^[2]

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1. Univ. of Rochester, NY (United States); OSTI
2. Univ. of Rochester, NY (United States); Chapman Univ., Orange, CA (United States)

Here, we study the phenomenon of absorption refrigeration, where refrigeration is achieved by heating instead of work, in two different setups: a minimal set up based on coupled qubits and two nonlinearly coupled resonators. Considering ZZ interaction between the two qubits, we outline the basic ingredients required to achieve cooling. Using local as well as global master equations, we observe that inclusion of an XX type term in the qubit-qubit coupling is detrimental to cooling. We compare the cooling effect obtained in the qubit case with that of nonlinearly coupled resonators (multilevel system) where the ZZ interaction translates to a Kerr-type nonlinearity. For small to intermediate strengths of nonlinearity, we observe that multilevel quantum systems, for example qutrits, give better cooling effect compared to the qubits. Using Keldysh nonequilibrium Green's function formalism, we go beyond first order sequential tunneling processes and study the effect of higher order processes on refrigeration. We find a reduced cooling effect compared to the master equation calculations.

• Research Organization: Univ. of Rochester, NY (United States); University of Rochester, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: SC0017890
• OSTI ID: 1852441
• Journal Information: Physical Review. B, Journal Name: Physical Review. B Journal Issue: 7 Vol. 104; ISSN 2469-9950
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English