Microwave electrodynamics of WP₂

We report on measurements of the microwave conductivity of WP₂ from 0.5 to 20 GHz and at low temperatures by way of bolometric broadband microwave spectroscopy. WP₂ is a recently discovered type-II Weyl semimetal that has been reported to host several anomalous transport properties, including a record-high residual resistivity ratio and magnetoresistance. Recent studies of the temperature-dependent electrical and thermal conductivities of WP₂ show that, at certain temperatures, electronic transport is in the hydrodynamic regime – in stark contrast to the diffusive transport found in most metals. Identification of the various scattering rates has thus far relied on measurement of DC quantities, whereas key signatures of charge dynamics are also manifested in the frequency dependence of these quantities. We will discuss our measurements of the microwave-frequency electrical conductivity in the context of hydrodynamic electronic transport in WP₂.