Published in PRR: Microkelvin electronics on a pulse-tube cryostat with a gate Coulomb-blockade thermometer

CBT220uK

Pushing the limits of on-chip temperatures deep into the microkelvin regime would open the door to unprecedented quantum coherence, novel quantum states of matter, and also the discovery of unexpected phenomena. Here, we present a pulse-tube compatible microkelvin sample holder with on-board demagnetization cooling and microwave filtering and introduce a new type of temperature sensor, the gate Coulomb blockade thermometer (gCBT), working deep into the microkelvin regime. Using on- and off-chip demagnetizaion cooling, we demonstrate electronic temperatures as low as 224±7 μK, remaining below 300 μK for 27 hours, thus providing sufficient time for measurements. Finally, we give an outlook for cooling below 50 μK for a new generation of microkelvin transport experiments.

Read more: UniNews: Ultracold circuits (Sept 22, 2022)

Samani, Scheller, Sharifi et. al., Phys. Rev. Research 4, 033225 (Sept 19, 2022), manuscript pdf