Large magnetoresistance and unexpected low thermal conductivity in topological semimetal CrP4 single crystal.

We fabricate CrP₄ single crystal under high pressure and high temperature at 5 GPa and 1373 K. The comprehensive physical properties including electronic transport, magnetic properties, specific heat, Hall, thermal Seebeck and thermal conductivity are reported here. The resistivity shows a good metallic conductivity and T^2.7 law relation in the low temperature, which indicates a weak correlation of electrons. It is interesting to note that CrP₄ shows large magnetoresistance (MR) of 500% under T = 2 K and B = 9 T, and the MR does not reach saturation until 9 T. The mechanism of large MR in CrP₄ is interpreted as the Fermi surface anisotropy. The Hall measurement shows that there is only one single type of carriers in CrP₄ with holes. CrP₄ exhibits paramagnetic behavior observed from the magnetic susceptibility measurement. Though CrP₄ exhibits high electrical conductivity, unexpected low thermal conductivity is observed at low temperature, which is due to the zigzag chain of CrP₆ octahedra along the c-axis. Low thermal conductivity is useful to design thermoelectric materials or devices by properly doping in CrP₄. [ABSTRACT FROM AUTHOR]