title: Photocurrent Mapping in Single-Crystal Methylammonium Lead Iodide Perovskite Nanostructures.
abstract: We investigate solution-grown single-crystal methylammonium lead iodide (MAPbI3) nanowires and nanoplates with spatially resolved photocurrent mapping. Sensitive perovskite photodetectors with Schottky contacts are fabricated by directly transferring the nanostructures on top of prepatterned gold electrodes. Scanning photocurrent microscopy (SPCM) measurements on these single-crystal nanostructures reveal a minority charge carrier diffusion length up to 21 μm, which is significantly longer than the values observed in polycrystalline MAPbI3thin films. When the excitation energy is close to the bandgap, the photocurrent becomes substantially stronger at the edges of nanostructures, which can be understood by the enhancement of light coupling to the nanostructures. These perovskite nanostructures with long carrier diffusion lengths and strong photonic enhancement not only provide an excellent platform for studying their intrinsic properties but may also boost the performance of perovskite-based optoelectronic devices.
authors.affiliation: Department of Physics, University of California , 1 Shields Avenue, Davis, California 95616, United States.
authors.forename: Rui
authors.initials: R
authors.lastname: Xiao
authors.affiliation: Department of Physics, University of California , 1 Shields Avenue, Davis, California 95616, United States.
authors.forename: Yasen
authors.initials: Y
authors.lastname: Hou
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States.
authors.forename: Yongping
authors.initials: Y
authors.lastname: Fu
authors.affiliation: Department of Physics, University of California , 1 Shields Avenue, Davis, California 95616, United States.
authors.forename: Xingyue
authors.initials: X
authors.lastname: Peng
authors.affiliation: Department of Physics, University of California , 1 Shields Avenue, Davis, California 95616, United States.
authors.forename: Qi
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Physics, California State University , 5500 University Parkway, San Bernardino, California 92407, United States.
authors.forename: Eliovardo
authors.initials: E
authors.lastname: Gonzalez
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706, United States.
authors.forename: Song
authors.initials: S
authors.lastname: Jin
authors.affiliation: Department of Physics, University of California , 1 Shields Avenue, Davis, California 95616, United States.
authors.forename: Dong
authors.initials: D
authors.lastname: Yu
keywords: Lead halide perovskite; carrier diffusion length; nanostructures; photocurrent; photonics; scanning photocurrent microscopy