Magnetic breakdown and the de Haas–van Alphen effect inHg1−xFexSe

Abstract

Measurements of the de Haas–van Alphen oscillations at T=0.55 K as a function of magnetic field direction in single crystal ${\mathrm{Hg}}_{1\mathrm{-}\mathrm{x}}$ ${\mathrm{Fe}}_{\mathrm{x}}$Se are reported. Spectral analysis using discrete Fourier transforms reveals the presence of up to six closely spaced frequency components. The angular dependence of the spectral content of the oscillations can be understood with a closed-orbit magnetic breakdown model. Using this model, the first and second harmonics of the de Haas–van Alphen signal for H?[111] can be fitted quantitatively. Estimates of the energy difference between the spin-split conduction bands are extracted from this analysis.