Rotational Quantum Friction via Spontaneous Decay

TL;DR

This paper explores rotational quantum friction acting on a diatomic polar molecule in free space, revealing a persistent zero-temperature friction torque and its dependence on rotational speed and quantum number.

Contribution

It introduces a quantized model of rotational quantum friction, analyzing dissipation due to spontaneous decay in both Markovian and non-Markovian regimes.

Findings

Friction torque scales as Ω^3 in the Markovian regime.

A linear Ω dependence of friction is observed in the non-Markovian short-time regime.

Friction persists at zero temperature, aligning with classical results for large quantum numbers.

Abstract

A fascinating effect belonging to the field of vacuum forces and fluctuations is that of quantum friction. It refers to the prediction of a dissipative force acting on a moving object due to the quantum vacuum field. In this work, we investigate rotational quantum friction where a diatomic polar molecule rotates around its own center of mass in free space. We quantize the rotational motion and investigate the resulting dissipation due to spontaneous decay. We find in the Markovian regime that a friction torque $\propto \Omega^3$ persists even for zero temperature, and in agreement with the classical result in the limit of large rotational quantum number $l$. Within the non-Markovian short-time regime we find a friction $\propto\Omega$.