Intrinsic and induced quantum quenches for enhancing qubit-based quantum noise spectroscopy.

ABSTRACT: Quantum sensing protocols that exploit the dephasing of a probe qubit are powerful and ubiquitous methods for interrogating an unknown environment. They have a variety of applications, ranging from noise mitigation in quantum processors, to the study of correlated electron states. Here, we discuss a simple strategy for enhancing these methods, based on the fact that they often give rise to an inadvertent quench of the probed system: there is an effective sudden change in the environmental Hamiltonian at the start of the sensing protocol. These quenches are extremely sensitive to the initial environmental state, and lead to observable changes in the sensor qubit evolution. We show how these new features give access to environmental response properties. This enables methods for direct measur

SUBMITTER: Wang YX 

PROVIDER: S-EPMC8586144 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature