Superconducting platinum silicide for electron cooling in silicon

We demonstrate electron cooling in silicon using platinum silicide as a superconductor contact to selectively remove the highest energy electrons. The superconducting critical temperature of bulk PtSi is reduced from around 1 K to 0.79 K using a thin film (10 nm) of PtSi, which enhances cooling performance at lower temperatures and enables electron cooling to be demonstrated from 100 mK to 50 mK.