An Exponential Bound in the Quest for Absolute Zero
For researchers in quantum thermodynamics and low-temperature physics, this work offers a fundamentally improved scaling law that could guide future experimental efforts toward reaching absolute zero.
The authors show that the minimum achievable temperature in a quantum parametric oscillator scales exponentially with process duration, an exponential improvement over the typical power-law scaling. This result provides a new theoretical bound for cooling to absolute zero.
In most studies for the quantification of the third thermodynamic law, the minimum temperature which can be achieved with a long but finite-time process scales as a negative power of the process duration. In this article, we use our recent complete solution for the optimal control problem of the quantum parametric oscillator to show that the minimum temperature which can be obtained in this system scales exponentially with the available time. The present work is expected to motivate further research in the active quest for absolute zero.