Acceptor Concentration Effects on Photovoltaic Response in the La_1-xSr_xMnO₃/SrNb_yTi_1-yO₃ Heterojunction

Photovoltaic response in the heterojunction of La_1-xSr_xMnO₃/SrNb_yTi_1-yO₃ (LSMO/SNTO) is analyzed theoretically based on the drift-diffusion model. It is found that the decrease of acceptor concentration in the La_1-xSr_xMnO₃ layer of heterojunction can increase the peak value of photovoltaic signal and the speed of photovoltaic response, whereas the changing of donor concentration in the SrNb_yTi_1-yO₃ layer has no such evident effect. Furthermore, the result also indicates that the modulation of Sr doping in La_1-xSr_xMnO₃ is an effective method to accommodate the sensitivity and the speed of photovoltaic response for LSMO/SNTO photoelectric devices.