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European Biophysics Journal

, Volume 35, Issue 3, pp 190–195 | Cite as

Study of optical properties of electropolymerized melanin films by photopyroelectric spectroscopy

  • José Eduardo de Albuquerque
  • Clare Giacomantonio
  • Andrew G. White
  • Paul Meredith
Article

Abstract

Photopyroelectric (PPE) spectroscopy, in the 350–1,075 nm wavelength range, was used to study the optical properties of electropolymerized melanin films on indium tin oxide (ITO) coated glass. The PPE intensity signal as a function of the wavelength λ, V n(λ) and its phase F n(λ) were independently measured. Using the PPE signal intensity and the thermal and optical properties of the pyroelectric detector, we were able to calculate the optical absorption coefficient β of melanin in the solid-state. We believe this to be the first such measurement of its kind on this material. Additionally, we found an optical gap in these melanin films at 1.70 eV.

Keywords

Melanin Photopyroelectric spectroscopy Optical properties 

Notes

Acknowledgements

J. E. de Albuquerque acknowledges UFV for sabbatical leave. This work was partially funded by the Australian Research Council (DP0345309) and by the MURI Center for Photonic Quantum Information Systems, ARO/ARDA Program No. DAAD19-03-1-0199.

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Copyright information

© EBSA 2005

Authors and Affiliations

  • José Eduardo de Albuquerque
    • 1
  • Clare Giacomantonio
    • 2
  • Andrew G. White
    • 2
  • Paul Meredith
    • 2
  1. 1.Departamento de FísicaUniversidade Federal de ViçosaViçosaBrazil
  2. 2.Soft Condensed Matter Physics Group, School of Physical SciencesUniversity of QueenslandBrisbaneAustralia

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