Nanoscale cryogenic thermometry via electron-phonon interaction in a dual quantum dot setup

Nanoscale cryogenic thermometry has gained particular concern owing to the rising demand for a few Kelvin applications. Temperature-controlled electronic transport is employed in nanoscale thermoelectric engines, refrigerators, transistors, and rectifiers. Similarly, electronic thermometry can be achieved via temperature-induced controlled electron flow. Here, we adopt a novel cryogenic thermometer setup compiled with an array of dual quantum dots. These dots share a stair-like ground state configuration triggering inelastic process-assisted tunneling in the system. The phonon scattering phenomenon gives rise to temperature-controlled thermometry in the setup. Further, we performed the thermometry analysis with the quantum master equation (QME) approach in a sequential tunneling limit. The analysis shows that the setup can manifest maximum temperature sensitivity and efficiency in the low temperature (a few Kelvin) regimes. Therefore, this dual quantum dot structure may become suitable for future realistic cryogenic thermometers coupled with high-performance temperature sensors at the nanoscale.