skip to main content

SciTech ConnectSciTech Connect

Title: Ultrafast free-carrier dynamics in Cu{sub 2}ZnSnS{sub 4} single crystals studied using femtosecond time-resolved optical spectroscopy

We studied the dynamics of photogenerated carriers in Cu{sub 2}ZnSnS{sub 4} (CZTS) single crystals using femtosecond transient reflectivity (TR) and optical pump-THz probe transient absorption (THz-TA) spectroscopy. The TR and THz-TA decay dynamics consistently showed that free carriers have long lifetimes of up to a few nanoseconds. The excitation-photon-energy-dependent TR measurements revealed a slow picosecond energy relaxation of free carriers to the band edge in CZTS. The relaxation and recombination dynamics of free carriers were affected by nonradiative recombinations at the surface. Our results revealed a global feature of energy relaxation and recombination processes of free carriers in CZTS single crystals.
Authors:
;  [1] ;  [2] ; ;  [1] ; ; ; ;  [3] ;  [4] ;  [2] ;  [5]
  1. Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan)
  2. (Japan)
  3. Graduate School of Engineering Science, Osaka University, Osaka 560-8531 (Japan)
  4. Department of Materials Science and Engineering, Kyoto University, Kyoto 606-8501 (Japan)
  5. Department of Applied Physics and Electronic Engineering, University of Miyazaki, Miyazaki 889-2192 (Japan)
Publication Date:
OSTI Identifier:
22395460
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 23; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION SPECTROSCOPY; CHARGE CARRIERS; COPPER COMPOUNDS; ENERGY DEPENDENCE; EXCITATION; LIFETIME; MONOCRYSTALS; PHOTONS; PROBES; RECOMBINATION; REFLECTIVITY; RELAXATION; SURFACES; THZ RANGE; TIME RESOLUTION; TIN SULFIDES; TRANSIENTS; ZINC COMPOUNDS