On fluctuations about non-equilibrium steady states near Gunn instability

Fluctuations about homogeneous and inhomogeneous non-equilibrium steady states near Gunn instability are studied. Density and electric field autocorrelation functions in Fourier and real spaces are calculated in the framework of generalized Landau-Lifshitz fluctuating hydrodynamics. Some properties of correlation functions as critical slowing down and long-range behaviour, common for systems away from equilibrium, are obtained. Critical behaviour is also investigated.