Transient Rayleigh Spectroscopy measure of Carrier Dynamics in Wurtzite and Zincblende InP nanowires

ORAL

Abstract

Pump-probe two color transient Rayleigh spectroscopy is used to study the carrier dynamics of the WZ and ZB InP nanowires. Both nanowires were grown by MOCVD with both diameters $\sim$100nm. Utilizing wavelength-tunable pulse laser generated by super-continuum fiber excited with Ti-Sapphire Laser and a time delay line adjusting the time difference between the pump and probe pulse, the change of the reflectivity as a function of excitation energy and time delay after pump can be measured from a single nanowire. The results are fitted based on the absorption coefficient calculated by a band to band transition model and index of refraction correlated by the Kramer-Kronig relation. The temperature of the electron-hole plasma(EHP) is cooled by the interaction with LO phonons and Acoustic phonons. The EHP-LO phonon cooling mechanism is dominating at early times from 0 to 200ps(ZB) and 500ps(WZ), after which the EHP-acoustic phonon interactions begin to contribute more. The carrier relaxation time constants were also fitted for different bands. The conduction bands of ZB and WZ InP show lifetimes of 1500ps and 2000ps, respectively. Both the Split-Off band in ZB InP and C band in WZ InP show slow relaxation time constants compared to the rest of the valence bands by a factor of 2-3.

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Authors

  • Yuda Wang

    Univ. of Cincinnati

  • John Royston

    Ball State University, Naval Research Laboratory, Washington, DC 20375, USA, Univ of Cincinnati, KITP China, U.C. Berkeley, FNAL, Cornell, West Virginia University, University of Pittsburgh, The Ohio State University, Carnegie Mellon University, Miami University, University of Notre Dame, University of Nebraska-Lincoln, Miami Univ, Australia National Univ., Miami Univ., Univ. of Cincinnati, Physics and Astronomy Department, Ohio University, Athens, OH 45701, Australian National University, University of Toledo, The University of Toledo, University of Toledo, Wright Center for Photovoltaics Innovation and Commercialization, University of Cincinnati, University of California, Davis

  • John Royston

    Ball State University, Naval Research Laboratory, Washington, DC 20375, USA, Univ of Cincinnati, KITP China, U.C. Berkeley, FNAL, Cornell, West Virginia University, University of Pittsburgh, The Ohio State University, Carnegie Mellon University, Miami University, University of Notre Dame, University of Nebraska-Lincoln, Miami Univ, Australia National Univ., Miami Univ., Univ. of Cincinnati, Physics and Astronomy Department, Ohio University, Athens, OH 45701, Australian National University, University of Toledo, The University of Toledo, University of Toledo, Wright Center for Photovoltaics Innovation and Commercialization, University of Cincinnati, University of California, Davis

  • John Royston

    Ball State University, Naval Research Laboratory, Washington, DC 20375, USA, Univ of Cincinnati, KITP China, U.C. Berkeley, FNAL, Cornell, West Virginia University, University of Pittsburgh, The Ohio State University, Carnegie Mellon University, Miami University, University of Notre Dame, University of Nebraska-Lincoln, Miami Univ, Australia National Univ., Miami Univ., Univ. of Cincinnati, Physics and Astronomy Department, Ohio University, Athens, OH 45701, Australian National University, University of Toledo, The University of Toledo, University of Toledo, Wright Center for Photovoltaics Innovation and Commercialization, University of Cincinnati, University of California, Davis

  • John Royston

    Ball State University, Naval Research Laboratory, Washington, DC 20375, USA, Univ of Cincinnati, KITP China, U.C. Berkeley, FNAL, Cornell, West Virginia University, University of Pittsburgh, The Ohio State University, Carnegie Mellon University, Miami University, University of Notre Dame, University of Nebraska-Lincoln, Miami Univ, Australia National Univ., Miami Univ., Univ. of Cincinnati, Physics and Astronomy Department, Ohio University, Athens, OH 45701, Australian National University, University of Toledo, The University of Toledo, University of Toledo, Wright Center for Photovoltaics Innovation and Commercialization, University of Cincinnati, University of California, Davis

  • John Royston

    Ball State University, Naval Research Laboratory, Washington, DC 20375, USA, Univ of Cincinnati, KITP China, U.C. Berkeley, FNAL, Cornell, West Virginia University, University of Pittsburgh, The Ohio State University, Carnegie Mellon University, Miami University, University of Notre Dame, University of Nebraska-Lincoln, Miami Univ, Australia National Univ., Miami Univ., Univ. of Cincinnati, Physics and Astronomy Department, Ohio University, Athens, OH 45701, Australian National University, University of Toledo, The University of Toledo, University of Toledo, Wright Center for Photovoltaics Innovation and Commercialization, University of Cincinnati, University of California, Davis

  • John Royston

    Ball State University, Naval Research Laboratory, Washington, DC 20375, USA, Univ of Cincinnati, KITP China, U.C. Berkeley, FNAL, Cornell, West Virginia University, University of Pittsburgh, The Ohio State University, Carnegie Mellon University, Miami University, University of Notre Dame, University of Nebraska-Lincoln, Miami Univ, Australia National Univ., Miami Univ., Univ. of Cincinnati, Physics and Astronomy Department, Ohio University, Athens, OH 45701, Australian National University, University of Toledo, The University of Toledo, University of Toledo, Wright Center for Photovoltaics Innovation and Commercialization, University of Cincinnati, University of California, Davis