Carrier Dynamics and Band Structure in InGaAs and InGaAs/InP Nanowires

ORAL

Abstract

We use transient Rayleigh scattering (TRS) measurements to explore the electronic energy structure of wurtzite InGaAs nanowires. We studied single core-only InGaAs nanowires as well as strained core-shell InGaAs-InP heterostructures at 300 K and 10 K, with probe photon energies in the near-infrared from 0.79 to 1.16 eV. We report a factor of four enhancement of the typical lifetime of excited states in the core-shell nanowires (~500 ps) when compared to the core-only nanowires (~125 ps). We observe a clear band-edge-like structure in the core-shell wires at energies of 0.98 eV at 10 K and 0.88 eV at 300 K. In both cases, this structure is at a significantly higher energy than the reported bandgap of bulk zincblende InGaAs of the same nominal composition as our nanowires. We also present a phenomenological fitting model of our TRS spectra which provides insight into the cooling dynamics of the electron-hole plasma within a single photo-excited nanowire.

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Authors

  • Samuel Linser

    Department of Physics, University of Cincinnati, Cincinati, OH, Department of Physics, University of Cincinnati, Cincinnati, OH

  • Iraj Shojaei

    Department of Physics, University of Cincinnati, Cincinati, OH, Department of Physics, University of Cincinnati, Cincinnati, OH

  • Giriraj Jnawali

    Department of Physics, University of Cincinnati, Cincinnati, OH, Department of Physics, University of Cincinnati, Cincinati, OH

  • Nadeeka Wickramasuriya

    Department of Physics, University of Cincinnati, Cincinati, OH, Department of Physics, University of Cincinnati, Cincinnati, OH

  • Howard Jackson

    Department of Physics, University of Cincinnati, Cincinnati, OH, Department of Physics, University of Cincinnati, Cincinati, OH

  • Leigh Smith

    Department of Physics, University of Cincinnati, Cincinnati, OH, Department of Physics, University of Cincinnati, Cincinati, OH

  • Amira Ameruddin

    Department of Electronic and Materials Engineering, Australian National University, Canberra, Australia

  • Philippe Caroff

    Department of Electronic and Materials Engineering, Australian National University, Canberra, Australia

  • Hoe Tan

    Department of Electronic and Materials Engineering, Australian National University, Canberra, Australia

  • Chennupati Jagadish

    Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, Australia, Department of Electronic and Materials Engineering, Australian National University, Canberra, Australia