Negative differential resistance and hysteresis in Au/MoO_3−δ/Au devices

Abstract

Metal/oxide/metal thin devices may exhibit hysteresis and negative differential resistance (NDR) under time-varying voltage at low temperatures that strongly depend on the frequency of the applied voltage.

Dynamic Current–Voltage Analysis of Oxygen Vacancy Mobility in Praseodymium‐Doped Ceria over Wide Temperature Limits

“…For a very high sweep rate of 10 V s −1 , the device response is ohmic, but for lower frequencies, the I–V curves become nonlinear, exhibiting hysteresis, a current peak and a negative differential resistance. If the frequency is reduced further, the I–V response (not shown here) remains nonlinear, but the hysteresis and the current peak disappear . An inset in Figure b shows a plot of reciprocal sweep rate, , versus time‐to‐current‐peak parameter squared, , for some of the shown I–V responses.…”

“…This was confirmed by reproducibility of the I–V response for multiple cycles. For less stable materials, the method can be applied by selecting lower triangular voltage amplitudes as was demonstrated previously . For a very high sweep rate of 10 V s −1 , the device response is ohmic, but for lower frequencies, the I–V curves become nonlinear, exhibiting hysteresis, a current peak and a negative differential resistance.…”

“…In the following, we provide a short review of the dynamic I – V analysis method and the assumptions made in its application. In general, the I–V relations (where the applied voltage, for instance, is a periodic triangular waveform) of a thin mixed ionic–electronic conductor placed between two ion blocking and electronically conducting electrodes are nonlinear if an applied voltage has a sufficiently high amplitude and low frequency . In that case, the I–V curve has a characteristic hysteretic shape, exhibiting a peak current followed by a region with a dynamic negative differential resistance (e.g., see Figure b).…”

“…In general, the I-V relations (where the applied voltage, for instance, is a periodic triangular waveform) of a thin mixed ionic-electronic conductor placed between two ion blocking and electronically conducting electrodes are nonlinear if an applied voltage has a sufficiently high amplitude and low frequency. [24,30] In that case, the I-V curve has a characteristic hysteretic shape, exhibiting a peak current followed by a region with a dynamic negative differential resistance (e.g., see Figure 3b). The hysteretic shape and peak current occur due to resistance changes induced by the drift and redistribution of the positively charged oxygen vacancies, and in turn, the electronic species, driven by the applied electrical field.…”

“…This approach is reviewed and further developed in the methods section below. The method was previously successfully applied in measuring oxygen vacancy mobilities in reduced molybdenum trioxide thin films at near ambient temperatures . Here, we use the dynamic I–V analysis to measure oxygen vacancy mobilities in ten percent praseodymium‐doped ceria, Pr 0.1 Ce 0.9 O 2− δ (PCO), MIEC thin films of interest as a cathode model material in SOFCs at elevated temperatures and for room temperatures nanoelectronic applications .…”