Precision Enhancement in Transient Quantum Thermometry:Cold-Probe Bias and Its Removal

Abstract

We unveil a temperature bias of the probe in transient quantum thermometry under Markovian dynamics. Specifically, for qubit thermometers evolving under Markovian dynamics, we show that enhanced precision beyond the steady state limit can be achieved if and only if the probe is initially colder than the thermal state corresponding to the bath temperature to be estimated. In contrast, this temperature bias can be lifted when the probe dynamics is non-Markovian. In the non-Markovian regime, both hot and cold probes can simultaneously attain the same transient maximum precision, well above the steady-state value.