Advertisement

Graphite as a Picosecond Laser Activated Opening Switch

  • E. A. Chauchard
  • Chi H. Lee
  • C. Y. Huang
  • A. M. Malvezzi
Conference paper
Part of the Springer Series in Electronics and Photonics book series (SSEP, volume 24)

Abstract

In a recent experiment, HUANG et al. [l] have observed a large decrease in the reflectivity of a semimetallic sample of highly oriented pyrolytic graphite (HOPG) as it is illuminated by an intense picosecond laser pulse when the fluence is above a well-defined threshold of 140 mJ/cm2 at 566 nm. They have found that the imaginary part of the refractive index reaches lower than 0.5 at 566 nm. This unexpected result indicates that a phase transformation occurs and that the high-temperature phase, which they believe to be liquid, is non-metallic. This experimental observation is consistent with the result of the recent pseudo-potential calculation that there is an energy gap in “isotropic” carbon [2]. The time-resolved experiments [l] also show that the phase transformation is completed in time scales as short as ~ 10 ps and that the new phase lasts for approximately 3 ns. In the work presented here, we directly assess the change of resistivity of a HOPG sample used as a laser-activated switch. We confirm the results reported in [l] by observing a large increase in the sample’s resistivity under intense picosecond laser illumination. This unique property could allow one to use graphite as an opening switch since its conductivity in the c-plane, in the dark state (σ ≅ 105 (Ohm.Cm)-1) is almost as good as that of pure copper. It could then be compared with semiconductor optoelectronic switches, noting that its operation is exactly inverse: it is conductive in the dark and its resistance increases when illuminated above the threshold.

Keywords

Transmission Line Switch Resistance Highly Orient Pyrolytic Graphite 2Los Alamos National Laboratory Picosecond Laser 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    C.Y. Huang, A.M. Malvezzi, N. Bloembergen and J.M. Lin: In Mat. Res. Symp. Proc. 51, 245 (1986); A.M. Malvezzi, N. Boembergen and C.Y. Huang: Phys. Rev. Lett. 57, 146–149 (1986).CrossRefGoogle Scholar
  2. 2.
    S. Fahy, S.G. Louie and M.L. Cohen: preprint.Google Scholar
  3. 3.
    K.H.. Schoenback, M. Kristiansen and G. Shoefer: Proc. IEEE 72, 8 (1984).Google Scholar
  4. 4.
    E.A. Chauchard, M.J. Rhee and Chi H. Lee: Appl. Phys. Lett. 47, 12 (1985).CrossRefGoogle Scholar
  5. 5.
    E.A. Chauchard, C.C. Kung, M.J. Rhee, Chi H. Lee and V. Diadiuk: Proc. of the Conference On Lasers and Electrooptics, ( San Francisco, CA 1986 ).Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1987

Authors and Affiliations

  • E. A. Chauchard
    • 1
  • Chi H. Lee
    • 1
  • C. Y. Huang
    • 2
  • A. M. Malvezzi
    • 3
  1. 1.Department of Electrical EngineeringUniversity of MarylandCollege ParkUSA
  2. 2.Los Alamos National LaboratoryLos AlamosUSA
  3. 3.Gordon McKay LaboratoryHarvard UniversityCambridgeUSA

Personalised recommendations