Dynamical conductivity of boron carbide: heavily damped plasma vibrations

作者：Werheit Helmut^*; Gerlach Guido

来源：Journal of Physics: Condensed Matter , 2014, 26(42): 425801.

DOI：10.1088/0953-8984/26/42/425801

• Boron carbide
• electronic transport
• dynamical conductivity
• plasma vibrations
• FIR reflectivity
• structural defects

The FIR reflectivity spectra of boron carbide, measured down to omega similar to 10 cm(-1) between 100 and 800 K, are essentially determined by heavily damped plasma vibrations. The spectra are fitted applying the classical Drude-Lorentz theory of free carriers. The fitting Parameter Pi = omega(p)/omega(tau) yields the carrier densities, which are immediately correlated with the concentration of structural defects in the homogeneity range. This correlation is proved for band-type and hopping conductivity. The effective mass of free holes in the valence band is estimated at mm(e) similar to 2.5. The mean free path of the free holes has the order of the cell parameters.

• 出版日期2014-10-22