Raman Study of the Temperature and Magnetic-Field Dependence of the Electronic and Lattice Properties of {{MnSi}}

The temperature and magnetic-field dependence of lattice and carrier excitations in MnSi is studied in detail using inelastic light scattering. The pure symmetry components of the electronic response are derived from the polarization-dependent spectra. The E and T2 responses agree by and large with longitudinal and optical transport data. However, an anomaly is observed right above the magnetic ordering temperature TC=29 K that is associated with the fluctuations that drive the transition into the helimagnetic phase first order. The T1 spectra, reflecting mostly chiral spin excitations, have a temperature dependence similar to that of the E and T2 symmetries. The response in the fully symmetric A1 representation has a considerably weaker temperature dependence than that in the other symmetries. All nine Raman active phonon lines can be resolved at low temperature. The positions and linewidths of the strongest four lines in E and T2 symmetry are analyzed in the temperature range 4     «

The temperature and magnetic-field dependence of lattice and carrier excitations in MnSi is studied in detail using inelastic light scattering. The pure symmetry components of the electronic response are derived from the polarization-dependent spectra. The E and T2 responses agree by and large with longitudinal and optical transport data. However, an anomaly is observed right above the magnetic ordering temperature TC=29 K that is associated with the fluctuations that drive the transition into t...     »