Cooling a long-range interacting system faster via applying an external magnetic field

If a mean-field spin ring interact with a cold external thermal reservoir, the system might first evolve to the paramagnetic metastable state along the paramagnetic path, and then fluctuate around the metastable state for a long period due to an energy barrier. The spin system must absorb sufficient energy from the thermal reservoir to achieve a phase transition to the final ferromagnetic equilibrium state. However, if an external magnetic field is applied to the system, the energy barrier becomes smaller, which can reduce the relaxation time of the system significantly. Moreover, if the magnetic intensity is strong enough, the energy barrier vanishes and the system evolves directly to the equilibrium state.

Automated summary

When a mean-field spin ring interacts with a cold external thermal reservoir, the system first evolves to the paramagnetic metastable state along the paramagnetic path and then fluctuates around the metastable state for a long time due to an energy barrier. To achieve a phase transition to the final ferromagnetic equilibrium state, the spin system needs to absorb enough energy from the thermal reservoir. However, applying an external magnetic field to the system reduces the energy barrier, significantly reducing the relaxation time. Furthermore, if the magnetic intensity is strong enough, the energy barrier disappears and the system evolves directly to the equilibrium state.