Harnessing thermal gradients in silicon quantum dots

Thermal gradients are common in semiconductor devices operated at cryogenic temperatures due to reduced thermal conductivity and weak electron-phonon coupling inhibiting thermalization. In quantum-dot systems, these gradients often appear unintentionally, for example through voltage pulses or currents. In this talk, we demonstrate that thermal gradients in a Si/SiGe quantum dot device can be harnessed to operate a charge sensor without an applied electric bias. We show that thermally biased charge sensors enable the measurement of both steady-state and instantaneous charge states, and we model our results using a Pauli master equation approach. Our results signify the potential for incorporating useful nanoscale thermal machines in complex quantum devices.