Numerical simulations of low-frequency noise in RuO_2-glass films

摘要

The paper deals with low-frequency noise in RuO_2-glass thick resistive films at low temperatures. Careful measurements performed with ac technique reveal that below liquid helium temperature and in the low frequency limit excess noise of the films is a pure resistance noise for low bias voltage, but at larger voltages depends sublinearly on voltage square. The model is proposed which shows that the observed noise suppression is due to inhomogeneous heating of devices under test. In this model conduction is via hopping and the noise is due to fluctuation of activation energies of the inter-site conductances. Numerical simulations show that there is an interesting scaling of noise that can be used to identify the local (microscopic) mechanism of heat transfer from electron to phonon systems.