Photoinduced Negative Differential Resistivity and Gunn Oscillations in SrTiO3

Abstract

SrTiO3, a perovskite oxide, holds significant potential for application in the field of oxide electronics. Notably, its photoelectric activity in the low temperature regime, which overlaps with the quantum paraelectric state, exhibits remarkable characteristics. In this study, it is demonstrated that when photo‐excited with above band gap energy photons, SrTiO3 exhibits non‐linear transport of photocarriers and voltage‐controlled negative resistance, resulting from an intervalley transfer of photo‐induced electrons. As a consequence of the negative resistance, the photocurrent becomes unstable and spontaneously gives rise to low frequency Gunn‐like oscillations.

Heterostructure of Reduced Titanium Dioxide Nanorods and Small Molecules Leads to Photo‐Induced Negative Differential Resistance Behaviors

“…[9,10] Recently, photoinduced NDR devices have emerged, where these devices exhibit typical diode characteristics in the dark state but demonstrate light-sensitive behavior with the emergence of NDR phenomena only when exposed to light. [11,12] Meanwhile, oblique angle deposition (OAD) is a deposition method employed in the production of nanostructured thin films tailored for cutting-edge optical nanodevices. [13] The concept of OAD possesses the alignment of source particles, which evaporate and deposit onto a substrate at a specific angle due to the shadowing effect and substrate rotation to precisely govern the formation of columnar and helical nanostructures within these thin films.…”