Nonequilibrium 1/f noise in low-doped manganite single crystals

作者：Wu X D^*; Dolgin B; Jung G; Markovich V; Yuzhelevski Y; Belogolovskii M; Mukovskii Ya M

来源：Applied Physics Letters, 2007, 90(24): 242110.

DOI：10.1063/1.2748083

1/f noise in current biased La0.82Ca0.18MnO3 crystals has been investigated. The temperature dependence of the noise follows the resistivity changes with temperature, suggesting that resistivity fluctuations constitute a fixed fraction of the total resistivity, independently of the dissipation mechanism and magnetic state of the system. The noise scales as a square of the current as expected for equilibrium resistivity fluctuations. However, at 77 K at bias exceeding some threshold, the noise intensity starts to decrease with increasing bias. The appearance of nonequilibrium noise is interpreted in terms of bias dependent multistep indirect tunneling.

• 出版日期2007-6-11