Alloys & Semiconductor Systems

Reflection Anisotropy Spectroscopy (RAS)

Long Term


Peter Weightman and Trevor Farrell

Research Overview

The primary aims of my research programme are:

  1. To determine the physical principles which control the behaviour of metals, alloys and semiconductors and their surfaces and interfaces.
  2. To determine the physical principles which control the molecular assembly of DNA and protein systems at metal/liquid interfaces on the nanoscale.
  3. To test theoretical ideas on the mechanisms of biological organisation.

The benefits of achieving these aims would include:

  • The design of alloys with desirable properties from first principles.
  • The control of band offsets in semiconductor devices.
  • The controlled structuring of surfaces for the assembly of nanostructures.
  • The assembly of DNA templates for fabrication and assembly of nanoscale systems.
  • The development of methods for rapid screening of DNA-DNA and DNA-protein interactions. This would remove a major limitation on the exploitation of the results of the human genome project in the development of pharmaceuticals.
  • Advances in the engineering of functionalisation of surfaces on the nanoscale for applications in clinical engineering.
  • An advance in our ability to exploit the self-assembly of biological molecules and insight into the development of disease.

I am currently concentrating on the development and application of Reflection Anisotropy Spectroscopy (RAS) for the study of biological systems and of a terahertz beamline and tissue culture facility on the ALICE accelerator at Daresbury for the study of biological systems. My research is set in the context of collaborations with other members of the Condensed Matter Group and the surface science research centre.

Selected Publications

            "Auger Vacancy Satellite Structure in the L3M4,5M4,5  Auger Spectra of Copper"
             E.D. Roberts, P. Weightman and C.E. Johnson, J.Phys. C 8 L301-4 (1975)

             "The M4,5N4,5 N4,5   Auger Spectra of Ag, Cd, In and Sn"
               A.C. Parry-Jones, P. Weightman and P. Andrews, J.Phys. C 12 1587-600 (1979)

             "The Influence of the 4d Bandwidth on the M4,5N4,5N4,5  Auger Spectra of Ag in MgAg and AlAg Alloys"
                P. Weightman and P.T. Andrews, J.Phys. C 13 3529-46 (1980)

             "The Pd Auger Spectra of Mg75Pd25, Al80Pd20 and Pd and their Dependence on Band Structure"
               P. Weightman and P.T. Andrews, J.Phys. C 13 L815-19 (1980)

             "The Pd M4,5N4,5N4,5  Auger Spectra of AgPd Alloys"
               P. Weightman and P.T. Andrews, J.Phys. C 13 L821-5 (1980)

             "Localised States in Molecular Auger Spectra"
              T.D. Thomas and P. Weightman, Chem. Phys. Lett. 81 325-9 (1981)

             "KVV Auger Spectrum of F2: The Importance of Hole-Hole Correlations"
               P. Weightman, T.D. Thomas and D.R. Jennison, J. Chem. Phys. 78  
1652-62 (1983)

             "Valence Electronic Structure of AuZn and AuMg Alloys Derived from a new way of analysing Auger
               parameter shifts"
               T.D. Thomas and P. Weightman, Phys. Rev. B 33 5406-13 (1986)

             "Experimental Determination of the Pd and Cu Densities of States in Cu75Pd25"
               H. Wright, P. Weightman, P. Andrews, W. Folkerts, C.F.J. Flipse,  G.A. Sawatzky,  D. Norman and H. Padmore,                                                                                                                                                  

               Phys. Rev. B 35 519-23 (1987)

             "Local Lattice Expansion Around Pd Impurities in Cu and its influence on the Pd
               Density of States:  An EXAFS and Auger Study"
               P. Weightman, H. Wright, S.D. Waddington, D. van der Marel, G.A. Sawatzky, G.P. Diakun and D. Norman,
               Phys. Rev. B 36 9098-106 (1987)

             "Charge transfer and core-hole screening in PbTe."
              S.D. Waddington, P. Weightman, J.A.D. Matthew and A.D.C. Grassie. Phys. Rev.B 39
10,239-45 (1989).

             "Off site contribution to electron correlation; an extension to the Hubbard model studied by Auger spectroscopy."
               C. Verdozzi, M. Cini, J.A. Evans, R.J. Cole, A.D. Laine, P.S. Fowles, L. Duo and P. Weightman.
               Europhys. Lett. 16
743-9 (1991).

             "A new high sensitivity Auger spectrometer."
               P. Weightman. Physica. Scripta. T41
277-80  (1992).

             “Nucleation and evolution of the Au-induced 5x2 structure on vicinal Si(111).”  
               J.D. O ’Mahony, J.F. McGilp, C.F.J. Flipse, P. Weightman and F.M. Leibsle. Phys. Rev. B 49 2527-35 (1994).

             “Madelung Potentials and Disorder Broadening of Core Photoemission Spectra in Random Alloys.”
               R.J. Cole, N.J. Brooks and P. Weightman,  Phys. Rev. Lett. 78   3777-80 (1997)

             “Sensitivity of Reflectance Anisotropy Spectroscopy to the Orientation of Ge  Dimers on Vicinal Si(001)”
               J.R. Power, P. Weightman, S. Bose, A.I. Shkrebtii and R. Del Sole, Phys. Rev. Lett. 80 3133-6 (1998).

             “Adsorbate azimuthal orientation from reflectance anisotropy spectroscopy.”  
               B.G. Frederick, J.R. Power, R.J. Cole, C.C. Perry, Q. Chen, S.Haq, Th. Bertrams, N.V. Richardson 
              and P. Weightman. Phys. Rev. Lett. 80 4490-3 (1998).

             “Reflection anisotropy spectroscopy: a new probe for the solid-liquid interface.”
               B. Sheriden, D.S. Martin, J.R. Power, S.D. Barrett, C.I. Smith, C.A. Lucas, R.J. Nichols
               and  P. Weightman, Phys. Rev. Lett. 85  4618-21 (2000).

             “A rapid reflectance anisotropy spectrometer.”
               P. Harrison, T. Farrell, A. Maunder, C.I. Smith and P. Weightman, Meas. Sci. Technol. 12 2185-91 (2001)

             “Auger Energy Shifts in fcc AgPd Random Alloys from Complete Screening Picture and Experiment.”
               W. Olovsson, I.A. Abrikosov, B. Johansson, A. Newton, R.J. Cole and P. Weightman,
               Phys. Rev. Lett. 92
226406-4 (2004)

             "Unoccupied states in the band gap of d-doped Si in GaAs probed by Auger resonance spectroscopy."                              
               M.D. Jackson, J.M.C. Thornton, D. Lewis, A. Robinson, M. Fahy, A. Aviary and P. Weightman
               Phys. Rev. B 71
75313 (2005)

             "Reflectance anisotropy spectra of the diamond (100) 2x1 surface: evidence of strongly bound surface state excitons."
               M. Palummo, O. Pulci, R. Del Sole, A. Marina, M. Schwitters, S.R. Haines, K.H. Williams, D.S. Martin,
               P. Weightman and J.E. Butler, Phys. Rev. Lett. 94
87404 (2005)

             "Orientation of ordered structures of cytosine and cytidine 5'-monophosphate adsorbed at Au(110)/liquid interfaces."
               P. Weightman, G.J. Dolan, C.I. Smith, M.C. Cuquerella, N.J. Almond, T. Farrell, D.G. Fernig, C. Edwards and          
               D.S. Martin, Phys. Rev. Lett. 96
86102 1-4 (2006) 

             "Reflection anisotropy spectroscopy study of the adsorption of sulfur-containing amino acids at the
               Au(110)/electrolyte interface."
               R.LeParc, C.I. Smith, M.C. Cuquerella, R.L. Williams, D.G. Fernig, C. Edwards, D.S. Martin and P. Weightman,
               Langmuir 22
3413-20 (2006)

             "Adsorption of Calf Thymus DNA on Au(110) studied by Reflection Anisotropy Spectroscopy."
               M.C. Cuquerella, C.I. Smith, D.G. Fernig, C. Edwards and P. Weightman,
               Langmuir 23
2078-82 (2007)

             "Evidence for protein conformational change at a Au(110)/protein interface."                                                                                                                                                                  

              H.L. Messiha, C.I. Smith, N.S. Scrutton and P. Weightman  Euro. Phys. Lett. 83 18004 1-5 (2008)


             "Azimuthal dependent reflection anisotropy spectroscopy of Ag(110) near the plasmon resonance energy."

            T. Farrell, P. Harrison, C.I. Smith, D.S. Martin and P. Weightman  Applied Physics Letters 93 191102 (2008


           "Detection of DNA hybridisation on a functionalised diamond surface using reflection anisotropy spectroscopy"

            C.I. Smith, A. Bowfield, M.C. Cuquerella, C.P. Mansley, T. Farrell, P. Harrison, D.S. Martin, D.G. Fernig, C. Edwards,

            J.E. Butler, R.J. Hammers, B. Sun, X. Wang and P. Weightman   Euro. Phys. Letters 85 18006 (2009)


            "A new uv reflection anisotropy spectroscopy spectrometer and its application to the Au(110) electrolyte surface"

            C.P. Mansley, T. Farrell, C.I. Smith, P. Harrison, A. Bowfield and P. Weightman   J. Phys. D: Applied Physics 42 115303 1-5 (2009)