What is Gunn Effect in Gunn Diode?

In some materials (III-V compounds such as GaAs and InP), after an electric field in the material reaches a threshold level, the mobility of electrons decrease as the electric field is increased, thereby producing negative resistance.



The I-V curves of a Gunn diode will help explain the effect. For low voltages (up to 1 volt perhaps), the Gunn diode behaves nearly as a linear resistor. Then