  Weyl semimetals are characterized by their bulk Weyl points -- conical band
touching points that carry a topological monopole charge -- and Fermi arc
states that span between the Weyl points on the surface of the material.
Recently, significant progress has been made towards understanding and
measuring the physical properties of Weyl semimetals. Yet, potential
applications remain relatively sparse. Here, we propose Weyl semimetal
nanowires as field-effect transistors, dubbed WEYLFETs. Specifically, applying
gradient gate voltage along the nanowire, an electrical field is generated that
effectively tilts the open surfaces, thus, varying the relative orientation
between Fermi arcs on different surfaces. As a result, perfect negative
refraction between adjacent surfaces can occur and longitudinal conductance
along the wire is suppressed. The WEYLFET offers a high on/off ratio with low
power consumption. Adverse effects due to dispersive Fermi arcs and surface
disorder are studied.
