Low temperature refrigeration by electron emission in a crossed-field gap

A method of refrigeration using thermal-field electron emission from nanoscale emitters of arbitrary work function in a vacuum crossed-field gap is proposed. With an external crossed magnetic field, an additional potential barrier near the anode is created to restrict the tunneling of low-energy electrons (below the Fermi energy) and thus provids a versatile cooling capability from 300 down to 10 K. Optimal conditions are determined numerically and analytically, which give local cooling power densities (per emitter) of about 600 kW/cm(2) (at 300 K), 2.7 kW/cm(2) (at 50 K), and 20 W/cm(2) (at 10 K). (c) 2006 American Institute of Physics.