We present first de Haas-van Alphen (dHvA) experiments on the quasi-two-dimensional (quasi-2D) organic metals α-(ET)2MHg(SeCN)4 (M = Tl or K) and compare the results with dHvA data of the isostructural organic superconductor α-(ET)2NH4Hg(SCN)4. The angular dependences of the single found dHvA frequency and the field-independent effective cyclotron mass, mc, perfectly follow the 2D 1/cos Θ behavior. From the observed spin-splitting zeros we unambiguously could extract the values of gμb. Comparison with mc strongly suggests a reduced electron-phonon coupling constant in the non-superconducting salts.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Materials Science(all)
- Condensed Matter Physics