Magnetic-field-induced superconductivity in layered organic molecular crystals with localized magnetic moments -: art. no. 100502

lambda-( BETS)(2)FeCl4 undergoes transitions from an antiferromagnetic insulator to a metal and then to a superconductor as a magnetic field is increased. We use a Hubbard-Kondo model to clarify the role of the Fe3+ magnetic ions in these phase transitions. In the high-field regime, the magnetic field acting on the electron spins is compensated by the exchange field H-e due to the magnetic ions. We show how H-e can be extracted from the observed splitting of the Shubnikov-de Haas frequencies. We predict the field range for field-induced superconductivity in other materials.