Spin-thermo-electronic oscillator based on inverse giant   magnetoresistance
  A spin-thermo-electronic valve with the free layer of exchange-spring type and inverse magnetoresistance is investigated. The structure has S-shaped current-voltage characteristics and can exhibit spontaneous oscillations when integrated with a conventional capacitor within a resonator circuit. The frequency of the oscillations can be controlled from essentially dc to the GHz range by the circuit capacitance. 
A. M. Kadigrobov, S. Andersson, Hee Chul Park, D. Radic, R. I.   Shekhter, M. Jonson, V. Korenivski
cond-mat.mes-hall