Two-tooth bosonic quantum comb for temporal-correlation sensing

Abstract:We characterize the causal structure of coherence transport in open bosonic systems using a two-tooth quantum comb. We show that, by mapping sequential interactions between a structured bosonic absorber and a long-lived coherent probe onto a process-tensor description, the probe functions as a temporal interferometer for environmental two-time correlations. We derive closed-form expressions for a nonmonotonic memory response arising from a competition between instantaneous thermal responsivity and the delay-dependent evolution of absorber correlations. By tuning the intertooth delay, the comb can enhance or suppress the net temperature imprint, providing direct access to population correlators and enabling discrimination of spectrally structured non-Markovian fluctuations from effective thermal noise. The protocol provides an explicit bosonic implementation of two-time thermal-correlation sensing, complementary to prior studies of memory effects in noisy quantum metrology.

arXiv:2601.10916 [quant-ph]

(or arXiv:2601.10916v3 [quant-ph] for this version)

https://doi.org/10.48550/arXiv.2601.10916 Focus to learn more arXiv-issued DOI via DataCite

arXivLabs is a framework that allows collaborators to develop and share new arXiv features directly on our website.

Both individuals and organizations that work with arXivLabs have embraced and accepted our values of openness, community, excellence, and user data privacy. arXiv is committed to these values and only works with partners that adhere to them.

Have an idea for a project that will add value for arXiv's community? Learn more about arXivLabs.