Enhanced precision of low-temperature quantum thermometry via dynamical con- trol

VICTOR MUKHERJEE; ANALIA ZWICK; ARNAB GHOSH; XI CHEN; GERSHON KURIZKI

Communications Physics

Nature

Lugar: London; Año: 2019 vol. 2

2399-3650

We consider a thermometer modelled by a dynamically-controlled multilevel quantum probe incontact with a bath. Dynamical control in the form of periodic modulation of the energy-levelspacings of the quantum probe can dramatically increase the maximum accuracy bound of low-temperatures estimation, by maximizing the relevant quantum Fisher information. As opposedto the diverging relative error bound at low temperatures in conventional quantum thermome-try, periodic modulation of the probe allows for low-temperature thermometry with temperature-independent relative error bound. The proposed approach may find diverse applications related toprecise probing of the temperature of many-body quantum systems in condensed matter and ultra-cold gases, as well as in different branches of quantum metrology beyond thermometry, for examplein precise probing of different Hamiltonian parameters in many-body quantum critical systems.