P. A. Shields

Publications (3)7.37 Total impact

• Source

  Available from: arxiv.org

  Article: Superlattice Magnetophonon Resonances in Strongly Coupled InAs/GaSb Superlattices

  R. S. Deacon, A. B. Henriques, R. J. Nicholas, P. A. Shields
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  ABSTRACT: We report an experimental study of miniband magnetoconduction in semiconducting InAs/GaSb superlattices. For samples with miniband widths below the longitudinal optical phonon energy we identify a new superlattice magnetophonon resonance (SLMPR) caused by resonant scattering of electrons across the mini-Brillouin zone. This new resonant feature arises directly from the drift velocity characteristics of the superlattice dispersion and total magnetic quantisation of the superlattice Landau level minibands. Comment: 9 pages, 8 figures, submitted to Phys. Rev. B
  01/2007;
• Article: Stark magnetophonon resonances in Wannier-Stark localized InAs/GaSb superlattices

  R. S. Deacon, R. J. Nicholas, P. A. Shields
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  ABSTRACT: We report an experimental study of high electric field magnetoconduction in semiconducting InAs/GaSb superlattices. This demonstrates that total quantization of the electronic states leads to conduction dominated by a combination of interwell and intrawell processes. The strongest conduction occurs for the triple Stark magnetophonon resonance where resonant interwell tunnelling coincides with (multiple) intrawell longitudinal optical phonon emission.
  Physical review. B, Condensed matter 08/2006; 74(12):121306.
• Source

  Available from: sinica.edu.tw

  Article: Chirality assignment of single-walled carbon nanotubes with strain.

  Lain-Jong Li, R J Nicholas, R S Deacon, P A Shields
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  ABSTRACT: Strain-induced band gap shifts that depend strongly on the chiral angle have been observed by optical spectroscopy in single-walled carbon nanotubes (SWCNTs). Uniaxial and torsional strains are generated by changing the environment surrounding the SWCNTs, using the surrounding D2O ice temperature or the hydration state of a wrapping polymer. These methods are used as diagnostic tools to determine the quantum number q and examine chiral vector indices for specific nanotubes.
  Physical Review Letters 11/2004; 93(15):156104. · 7.37 Impact Factor