High-sensitivity photovoltaic responses in manganite-based heterojunctions on Si substrates for weak light detection

摘要

We have fabricated and characterized a weak light photodetector in a heterojunction composed of manganite La_(0.4)Ca_(0.6)MnO_(3) and n-type Si. High-sensitivity photoresponse properties were investigated. The responsivities of open-circuit photovoltage and short-circuit photocurrent reach approx1000 V/mJ and approx30 A/mJ, respectively, without any amplification bias under irradiation by 20-ps-wide and 355, 532, and 1064-nm-wavelength laser pulses in nanojoule to microjoule order. The present results demonstrate that the manganite-based heterojunction on Si substrate has potential applications in weak light detection from ultraviolet to near-infrared light.