摘要
We report on the photodetector structures based on perovskite manganite La0.67Ca0.33MnO3 thin films on tilted SrTiO3 (001) substrates. The photovoltaic effect has been observed in response to excitation by 308 nm ultraviolet laser pulse irradiation in duration of 20 ns at room temperature. The outputs ob- tained required no amplification. To reduce the deformation of the signal detected, a series of testing measurements were made to investigate the impedance effect. When the impedance at the oscilloscope end matched to the co-axis cable, the signal trace was almost triangular and symmetrical, with re- sponse time equal to the excitation laser. In addation, the response linearly depends on the irradiated area for low on-sample energy. The devices work well under unbiased conditions and so are simple to configure for practical applications.
We report on the photodetector structures based on perovskite manganite La0.67Ca0.33MnO3 thin films on tilted SrTiO3 （001） substrates. The photovoltaic effect has been observed in response to excitation by 308 nm ultraviolet laser pulse irradiation in duration of 20 ns at room temperature. The outputs obtained required no amplification. To reduce the deformation of the signal detected, a series of testing measurements were made to investigate the impedance effect. When the impedance at the oscilloscope end matched to the co-axis cable, the signal trace was almost triangular and symmetrical, with response time equal to the excitation laser. In addation, the response linearly depends on the irradiated area for low on-sample energy. The devices work well under unbiased conditions and so are simple to configure for practical applications.
基金
the National Natural Science Foundation of China (Grant Nos. 50672132, 60576015 and 60778034)
the Key Project of the Ministry of Educa-tion of China (Grant No. 107020)
关键词
水锰矿
光电探测器
薄膜
阻抗效应
manganite, photodetector, thin film, impedance effect
