Magnetic, electronic and transport properties of high-pressure-synthesized chiralmagnets Mn${}_{1-x}$Rh${}_x$Ge (B20)

Abstract

We report on structural, magnetic and transport properties of a new set of the high-pressuresynthesized compounds Mn${}_{1-x}$Rh$x$Ge ($0\le x\le 1$) with the chiral magnetic ordering. The magnetic and transport properties depend substantially on the concentration of rhodium (x) and the pressure. The saturation magnetic moment corresponds to a known high-spin value for pristine MnGe (x = 0) and decreases almost linearly with increasing concentration $x$. In addition, XMCD spectra taken at 10 K and 2 T indicate magnetic polarization of the Rh 4d electron states and Ge $4p$ states, which decreases with $x$, too. In rhodium rich compounds ($x\ge 0.5$) the temperature of the magnetic ordering increases significantly with pressure, whereas in manganese rich compounds ($x<0.5$) the temperature decreases. Three different tendencies are also found for several structural and transport properties. In the intermediate range ($0.3\le x\le 0.7$) samples are semiconducting in the paramagnetic phase, but become metallic in the magnetically ordered state. We carried out ab initio density-functional calculations of Mn${}_{1-x}$Rh${}_x$Ge at various concentrations $x$ and traced the evolution of electronic and magnetic properties. The calculation results are in good agreement with the measured magnetic moments and qualitatively explain the observed trends in transport properties.

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Cited by in corpus (4)

• Helicity-tunable spin Hall and spin Nernst effects in unconventional chiral fermion semimetals XY (X=Co, Rh; Y=Si, Ge)
• Theoretical and experimental study of high-pressure synthesized B20-type compounds Mn${}_{1-x}$(Co,Rh)${}_x$Ge
• Electronic and dynamical properties of cobalt monogermanide CoGe phases under pressure
• Ab initio study of noncentrosymmetric transition-metal monogermanide B20-RhGe synthesized at high temperature and pressure