Competition between Pauli and orbital effects in a charge-density-wave system

Abstract

We present angular-dependent magnetotransport and magnetization measurements on $\ensuremath{\alpha}\ensuremath{-}(\mathrm{ET}{)}_{2}\mathrm{MHg}(\mathrm{SCN}{)}_{4}$ compounds at high magnetic fields and low temperatures. We find that the low-temperature ground state undergoes two subsequent field-induced density-wave-type phase transitions above a critical angle of the magnetic field with respect to the crystallographic axes. This new phase diagram may be qualitatively described assuming a charge-density-wave ground state which undergoes field-induced transitions due to the interplay of Pauli and orbital effects.