Modern quantum sensors on the basis of ultra-cold atoms allow for an unprecedented experimental accuracy and have shown to be useful in fundamental science and real-world applications alike. With the advent of integration and miniaturization of such systems, the shrinking dimension of the setup leads to an increasing impact of the environment on the atoms’ dynamics.
To name only a few examples, thermal and quantum fluctuations, fluctuating-near-fields in the vicinity of a surface, or decoherence due to system+bath coupling will fundamentally limit the uncertainty of the experiment.
We explore the use of stochastic methods, i.e. the quantum Langevin equation, to describe the fundamental uncertainties in nonequilibrium atom-field interactions. To this end, we determine thermodynamic quantities such as dissipated power or the density matrix of the evolving system which can ultimately lead to a concise quantification of fundamental uncertainties. Our approach can be of use in the design and interpretation of future generations of quantum sensors.
D. Reiche, F. Intravaia, and K. Busch, APL Photonics 7, 030902 (2022).