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Magnetically controlled quantum thermal devices via three nearest-neighbor coupled spin-1/2 systems
Yi-Jia Yang1, Yu-Qiang Liu1, Zheng Liu1
1School of Physics, Dalian University of Technology, Dalian 116024, China.
Physical Review. E
|February 17, 2024
Summary
This study proposes a quantum thermal device using coupled spin systems. Magnetic fields control heat current, enabling perfect thermal modulation and enhanced transistor amplification.
Area of Science:
- Quantum thermodynamics
- Condensed matter physics
- Spin systems
Background:
- Quantum thermal devices offer novel ways to control energy transport.
- Spin-1/2 systems provide a platform for quantum information and thermodynamics.
Purpose of the Study:
- To propose and analyze a quantum thermal device based on three coupled spin-1/2 systems.
- To investigate the device's steady-state thermal behaviors and control capabilities.
- To explore its potential as a thermal modulator and transistor.
Main Methods:
- Theoretical modeling of a three-spin system coupled to thermal reservoirs.
- Analysis of steady-state heat current under magnetic field control.
- Investigation of system behavior with longitudinal and transverse magnetic fields.
Main Results:
- The system acts as a perfect thermal modulator, blocking heat current with a longitudinal magnetic field.
- Thermal modulation is achievable even with a third reservoir perturbing the middle spin.
- A transverse field allows control over heat current by separating the system into subspaces.
- Enhanced transistor amplification behaviors are observed with magnetic field control.
Conclusions:
- The proposed quantum thermal device offers versatile control over heat current.
- Magnetic field manipulation enables perfect thermal modulation and transistor functionalities.
- This work opens avenues for advanced quantum thermal management and devices.
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