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Title: Sub-millisecond response time in a photorefractive composite operating under CW conditions

Extensive study of photorefractive polymeric composites photosensitized with semiconductor nanocrystals has yielded data indicating that the inclusion of such nanocrystals enhances the charge-carrier mobility, and subsequently leads to a reduction in the photorefractive response time. Unfortunately, the included nanocrystals may also act as a source of deep traps, resulting in diminished diffraction efficiencies as well as reduced two beam coupling gain coefficients. Nonetheless, previous studies indicate that this problem is mitigated through the inclusion of semiconductor nanocrystals possessing a relatively narrow band-gap. Here, we fully exploit this property by doping PbS nanocrystals into a newly formulated photorefractive composite based on molecular triphenyldiamine photosensitized with C 60. Through this approach, response times of 399 μs are observed, opening the door for video and other high-speed applications. It is further demonstrated that this improvement in response time occurs with little sacrifice in photorefractive efficiency, with internal diffraction efficiencies of 72% and two-beam-coupling gain coefficients of 500 cm –1 being measured. A thorough analysis of the experimental data is presented, supporting the hypothesized mechanism of enhanced charge mobility without the accompaniment of superfluous traps. As a result, it is anticipated that this approach can play a significant role in the eventual commercialization ofmore » this class of materials.« less
 [1] ;  [2] ;  [2] ;  [2] ;  [3] ;  [3] ;  [4]
  1. Missouri Univ. of Science and Technology, Rolla, MO (United States); Pusan National Univ., Busan (Korea)
  2. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
  3. Pusan National Univ., Busan (Korea)
  4. Missouri Univ. of Science and Technology, Rolla, MO (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 2045-2322; 647132
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 6; Journal ID: ISSN 2045-2322
Research Org:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
OSTI Identifier: