Characterization of a Weyl semimetal using a unique feature of surface plasmon polaritons
Kota Tsuchikawa, Satoru Konabe, Takahiro Yamamoto, Shiro Kawabata
Abstract
We theoretically investigate the decay constant of surface plasmon polaritons in a Weyl semimetal and propose an experimental method for detecting Weyl semimetals. It is revealed that the surface plasmon polariton in a Weyl semimetal exhibits various characteristics depending on the plasmon wave vector. It can be a pure surface wave, a pseudosurface wave that couples with a bulk plasmon, or a generalized surface wave with complex decay constants. Such diverse surface plasmon characteristics are peculiar to Weyl semimetals that obey axion electrodynamics. The results suggest that the measurement of the decay length, the inverse of the decay constant, can be a powerful experimental probe for identifying Weyl semimetals.