Shubnikov - de Haas measurements of highly pressurized (ET)2TlHg(SCN)4

Abstract We have measured the change in the fundamental Shubnikov-de Haas (SdH) frequency of (ET) 2 TlHg(SCN) 4 in the pressure range 0–5.0 GPa. We find that the SdH frequency increases linearly in the pressure range 0–3.0 GPa with dF dP = 110±20 T/GPa ; at pressures above 3.0 GPa, however, the fundamental frequency drops drastically — roughly by a factor of three — suggesting that a pressure induced change in the bandstructure has occurred.