Stereoscopic study of the angle-dependent magnetoresistance oscillations across the charge-density-wave transition of the organic conductor α-(BEDT-TTF)₂KHg(SCN)₄

The stereoscopic angle-dependent magnetoresistance oscillations (AMRO) in an organic conductor α-(BEDT-TTF)₂KHg(SCN)₄ were measured across the temperature-pressure boundary that separates the charge-density-wave state from the metallic state. The gnomonic projections of the data clearly resolved the contributions from different parts of the Fermi surfaces. The temperature and pressure dependencies of the AMRO results revealed the progressive formation of a quasi-one-dimensional orbit in the charge-density-wave state. The AMRO measurements at ambient pressures and at low temperatures revealed the presence of two sets of quasi-one-dimensional Fermi surfaces. Additional evidence for multiple quasi-one-dimensional orbits was obtained from the data collected in conjunction with the in-plane field rotations.