Thermovoltaic Evidence for Electronic Knudsen Flow through Silicon Microcontacts

Abstract

Asymmetric heat generation is detected by Seebeck-voltage measurements in currentcarrying microcontacts, produced by adjoining two wedges of $n$-type silicon in ultrahigh vacuum. Decreasing the contact dimensions increases this asymmetry, which arises in the Knudsen regime of ballistic electron transport when the geometric dimensions of the contacts are sufficiently reduced to become comparable to the electron mean free path.