Field emission from Dirac and Weyl semimetals

Based on theoretical investigation on characteristics of the field emission current of Dirac/Weyl semimetals, the dependence of the field emission current on the applied bias is deduced and studied. This theoretical study demonstrates that the field emission current of a Dirac semimetal is much smaller than that of a conventional material when they have similar carrier parameters. This makes Dirac semimetal a better candidate for gate/base electrode material than gold and other conventional metals for an ultra-thin gate oxide metal–oxide–semiconductor field effect transistor. The field emission current of a Dirac semimetal decreases with the effective electron mass, while it increases for a conventional material. This implies that such an effective mass dependence can be used as a simple criterion to probe a Dirac semimetal in practice.