Soleimany Mehrzad, Alexe Marin
Department of Physics, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK.
Department of Materials and Earth Sciences, Technical University of Darmstadt, 64287, Darmstadt, Germany.
Adv Sci (Weinh). 2023 Dec;10(35):e2306420. doi: 10.1002/advs.202306420. Epub 2023 Oct 23.
SrTiO , 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, SrTiO 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.
钛酸锶（SrTiO₃）是一种钙钛矿氧化物，在氧化物电子学领域具有巨大的应用潜力。值得注意的是，它在低温区域的光电活性与量子顺电态重叠，呈现出显著的特性。在本研究中，结果表明，当用高于带隙能量的光子进行光激发时，钛酸锶（SrTiO₃）会出现光载流子的非线性传输和压控负电阻，这是由光致电子的谷间转移引起的。由于负电阻的存在，光电流变得不稳定，并自发产生低频耿氏（Gunn）样振荡。
