R(T) curves of a LSMO microbridge measured at two different fields (H = 0 and H = 50 kOe). Inset: Temperature dependence of the magnetization of LSMO samples.
(a) Picture of the microcircuit used for electronic transport measurements. (b) I-V characteristic curve measured at TBase = 182 K showing thenon-linear character and the existence of irreversibility as well as the change of the temperature of the LSMO microbridge while measuring the I-V curve.
(a) Dependence of the I-V characteristic curves on the TBase. (b) Differential conductivity (dI/dV) obtained from I-V curves at several TBase to illustrate the existence of negative differential conductivity around the jump in resistance in I-V curves.
(a) Variation of the microbridge resistance (R = V/I) obtained from I-V curves at TBase = 100 K. The arrows and numbers indicate the sense and order in which I-V curves have been scanned. The figure clearly shows that irreversibility appears when Vmax increases, i.e., current density rises up. (b) Variation of the actual temperature of the LSMO microbridge while measuring the I-V curves shown in (a). Inset: Variation of the actual temperature of the microbridge while measuring the I-V curves as a function of the power dissipated.
Resistance (R = V/I) of the LSMO microbridge obtained at a different TBase in the low voltage regime (|Vmax| ≤ 5 V) and replotted at the actual temperature of the microbidge in comparison with the R(T) curve obtained at low current, i.e., in thermal equilibrium. Inset: I-V curves at several TBase. Note that at low temperature measurements are made in current-limited mode to avoid sample damage, therefore, the power compliance of the measuring system is reached before arriving at the voltage bias limit.
R(T) measurements in constant current mode in the low current regime after scanning I-V curves in the high voltage regime (|Vmax| ≤ 10 V). Irreversible changes have occurred in the samples with a strong increase of the resistance and notorious decrease of TC.
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