Cormac Mc Guinness
Assistant Professor, Physics

Biography

Born in Dublin. Schooled at Oatlands College CBS Stillorgan. Educated in UCD. Obtained Doctorate in UCD. Postdoctoral research in DCU and UCD. Lecturing position in UCD. Postdoctoral research in Boston University. Research Associate Professor in Boston University. Appointed Lecturer in TCD. Married with two daughters.

Publications and Further Research Outputs

Peer-Reviewed Publications

E. Norton, L. Farrell, S. D. Callaghan, C. McGuinness, I. V. Shvets and K. Fleischer, X-ray spectroscopic studies of the electronic structure of chromium-based p-type transparent conducting oxides, Physical Review B, 93, 2016, p115302- Journal Article, 2016 URL TARA - Full Text

Pokle A, Coelho J, Macguire E, Downing C, Casey P, Park S.H, McGuinness C, Nicolosi V, EELS probing of lithium based 2-D battery compounds processed by liquid phase exfoliation, Nano Energy, 30, 2016, p18 - 26 Journal Article, 2016 URL DOI

Duignan, M.J., Cunniffe, J.P., Glans, P.-A., (...), Mcguinness, C., Mcgilp, J.F. , Temperature dependent studies of capped magnetic nanowires using XMCD, physica status solidi (b), 253, (2), 2016, p241-246 Journal Article, 2016 DOI

de Pedro, B., Parrondo, J., Meskell, C., Oro, J.F., CFD modelling of the cross-flow through normal triangular tube arrays with one tube undergoing forced vibrations or fluidelastic instability, Journal of Fluids and Structures, 64, 2016, p67-86 Journal Article, 2016 DOI

Barrier, E., Braz Fernandes, F.M., Bujan, M., (...), Stangl, J., Zanotti, G., The benefit of the European User Community from transnational access to national radiation facilities, Journal of Synchrotron Radiation, 21, (3), 2014, p638-639 Journal Article, 2014 TARA - Full Text DOI

Nolan H, McEvoy N, Keeley GP, Callaghan SD, McGuinness C, Duesberg GS, Nitrogen-doped pyrolytic carbon films as highly electrochemically active electrodes., Physical chemistry chemical physics : PCCP, 15, (42), 2013, p18688-18693 Journal Article, 2013 TARA - Full Text DOI

Krishnamurthy, S., Kennedy, B., Mcgee, F., Venkatesan, M., Coey, J.M.D., Lunney, J.G., Learmonth, T., (...), Mcguinness, C., Resonant soft X-ray emission and X-ray absorption studies on Ga1-xMnxN grown by pulsed laser deposition, Physica Status Solidi (C) Current Topics in Solid State Physics, 8, (5), 2011, p1608-1610 Journal Article, 2011 DOI

L. F. J. Piper, S. W. Cho, Y. Zhang, A. DeMasi, K. E. Smith, A. Y. Matsuura and C. McGuinness, Soft x-ray spectroscopy study of the element and orbital contributions to the electronic structure of copper hexadecafluoro-phthalocyanine, Physical Review B: Condensed Matter and Materials Physics, 81, (4), 2010, p045201:1 - 045201:13 Journal Article, 2010 URL TARA - Full Text

J. P. Cunniffe, D. E. McNally, M. Liberati, E. Arenholz, C. McGuinness, and J. F. McGilp, X-ray magnetic circular dichroism and reflection anisotropy spectroscopy Kerr effect studies of capped magnetic nanowires, Physica Status Solidi B, 247, (8), 2010, p2108 - 2112 Journal Article, 2010

T. Learmonth, C. McGuinness, P.-A. Glans, B. Kennedy, J. St.John, J.-H. Guo, M. Greenblatt, K. E. Smith, Resonant Soft X-Ray Inelastic Scattering and Soft X-Ray Emission Study of the Electronic Structure of alpha-MoO3, Physical Review B: Condensed Matter and Materials Physics, 79, 2009, p035110 - 035110-8 Journal Article, 2009 TARA - Full Text DOI

B. N. Holland, N. Peltekis, T. Farrelly, R. G. Wilks, G. Gavrila, D. R. T. Zahn, C. McGuinness, I. T. McGovern, NEXAFS studies of copper phthaloyanine on Ge(001)-2 × 1 and Ge(111)-c(2 × 8) surfaces, physica status solidi (b), 246, (7), 2009, p1546 - 1551 Journal Article, 2009

B. Arnold, S. Krishnamurthy, B. Kennedy, D. Cockburn, D. McNally, J. G. Lunney, R. Gunning, M. Venkatesan, J Alaria, J. M. D. Coey and C. McGuinness, Growth and characterisation of Al1-xCrxN thin fims by RF plasma assisted pulsed laser deposition., e-Journal of Surface Science and Nanotechnology, The 14th International Conference on Solid Films and Surfaces , April 4, 7, 2009, pp497-502 Conference Paper, 2009 DOI

B. N. Holland, G. Gavrila, D. R. T. Zahn, A A Cafolla, C. McGuinness, and I. T. McGovern, Adsorption of lead phthalocyanine on the hydrogen-passivated Ge(001)-2x1 surface, physica status solidi (c), 7, (2), 2009, p218 - 221 Journal Article, 2009 DOI

A. DeMasi, L. F. J. Piper, Y. Zhang, I. Reid, S. Wang, K. E. Smith, J. E. Downes, N. Peltekis, C. McGuinness, A. Matsuura, Electronic Structure of the Organic Semiconductor Alq3 (aluminum tris-8-hydroxyquinoline) from Soft X-ray Spectroscopies and Density Functional Theory Calculations, Journal of Chemical Physics, 129, 2008, p224705 - 224705-7 Journal Article, 2008

B.N. Holland, G. Cabailh, N. Peltekis, C. McGuinness, A.A. Cafolla, I.T. McGovern, Arrangement of metal phthalocyanines on Ge (0 0 1) 2 x 1 surfaces, Applied Surface Science, 255, (3), 2008, p775 - 777 Journal Article, 2008

C. Banahan, C. McGuinness, J. T. Costello, D. Kilbane, J. P. Mosnier, E. T. Kennedy, G. O'Sullivan, P. van Kampen, The 5d photoabsorption spectra of Pb III and Bi IV, Journal of Physics B-Atomic Molecular and Optical Physics, 41, (20), 2008, p205001 - 205001-9 Journal Article, 2008

N. Peltekis, B. N. Holland, S. Krishnamurthy, I. T. McGovern, N. R. J. Poolton, S. Patel, and C. McGuinness, Electronic and Optical Properties of Magnesium Phthalocyanine (MgPc) Solid Films Studied by Soft X-Ray Excited Optical Luminescence and X-Ray Absorption Spectroscopies, Journal of American Chemical Society, 130, (39), 2008, p13008 - 13012 Journal Article, 2008

B N Holland, G Cabailh, N Peltekis, C McGuinness, A A Cafolla, and I T McGovern, Arrangement of metal phthalocyanines on Ge 2x1 surfaces, Applied Surface Science , 255, (3), 2008, p775 - 777 Journal Article, 2008 DOI

T. Learmonth, P.-A. Glans, C. McGuinness, L. Plucinski, Y. Zhang, J.-H. Guo, M. Greenblatt, K. E. Smith, Electronic structure of the 1D conductor K0.3MoO3 studied using resonant inelastic x-ray scattering and soft x-ray emission spectroscopy, Journal of Physics: Condensed Matter, 20, 2008, p415219 - 415219-6 Journal Article, 2008

N. Peltekis, B.N. Holland, L.F.J. Piper, A. DeMasi, K.E. Smith, J.E. Downes, I.T. McGovern, C. McGuinness, The local electronic structure of tin phthalocyanine studied by resonant soft X-ray emission spectroscopies, Applied Surface Science, 255, (3), 2008, p764 - 766 Journal Article, 2008

T. Learmonth, C. McGuinness, P.-A. Glans, J. E. Downes, T. Schmitt, L.-C. Duda, J.-H. Guo, F. C. Chou and K. E. Smith, Observation of multiple Zhang-Rice excitations in a correlated solid: Resonant inelastic X-ray scattering study of Li2CuO2, Euro Physics Letters, 79, (4), 2007, p47012 - 47017 Journal Article, 2007

Y. Zhang, J. E. Downes, S. Wang, T. Learmonth, L. Plucinski, A. Y. Matsuura, C. McGuinness, P.A. Glans, S. Bernardis, C. O'Donnell and K. E. Smith, Electronic structure in thin film organic semiconductors studied using soft x-ray emission and resonant inelastic x-ray scattering, Thin Solid Films, 515, (2), 2006, p394 - 400 Journal Article, 2006

G. Cabailh, B.N. Holland, C. Stephens, I.T. McGovern, C. McGuinness, A. Cafolla, A.R. Vearey-Roberts and D.A. Evans, Soft X-ray photoelectron spectroscopy of metal-phthalocyanines on the (001) surface of GaAs and Ge, Journal de Physique IV, 132, 2006, p11 - 15 Journal Article, 2006 URL

S. Krishnamurthy, C. McGuinness, L. S. Dorneles, M. Venkatesan, J. M. D. Coey, J. G. Lunney, C. H. Patterson, K. E. Smith, T. Learmonth, P.A. Glans, T. Schmitt, J.-H. Guo, Soft x-ray spectroscopic investigation of ferromagnetic Co-doped ZnO, Journal of Applied Physics, 99, (08M111), 2006, p1 - 3 Journal Article, 2006 TARA - Full Text DOI

Nicolosi V, Vrbanic D, Mrzel A, McCauley J, O'Flaherty S, McGuinness C, Compagnini G, Mihailovic D, Blau WJ, Coleman JN, Solubility of Mo6S4.5I4.5 nanowires in common solvents: A sedimentation study, The Journal of Physical Chemistry B, 109, (15), 2005, p7124 - 7133 Journal Article, 2005 DOI

Cormac McGuinness, James E. Downes, Paul Sheridan, P.-A. Glans, Kevin E. Smith, W. Si, Peter D. Johnson, X-ray spectroscopic study of the electronic structure of the high-dielectric-constant material CaCu3Ti4O12, Physical Review B, 71, (19), 2005, p195111 - 195111-9 Journal Article, 2005 TARA - Full Text URL

Downes, J. E., McGuinness, C., Glans, P.-A., Learmonth, T., Fu, D., Sheridan, P. and Smith, K. E., Electronic structure near the Fermi level of the organic semiconductor copper phthalocyanine, Chemical Physics Letters, 390, 2004, p203 - 207 Journal Article, 2004

Glans PA, Learmonth T, McGuinness C, Smith KE, Guo JH, Walsh A, Watson GW, Egdell RG, On the involvement of the shallow core 5d level in the bonding in HgO, CHEMICAL PHYSICS LETTERS, 399, (1-3), 2004, p98 - 101 Journal Article, 2004

Valla, T., Fedorov, A. V., Johnson, P. D., Glans, P. A., McGuinness, C., Smith, K. E. and Berger, H., Quasiparticle spectra, charge-density-wave, superconductivity and electron-phonon coupling in 2H-NbSe2, Physical Review Letters, 92, (8), 2004, p086401 - 1:086401-4 Journal Article, 2004

McGuinness, C., Stagarescu, C.B., Ryan, P.J., Downes, J.E., Fu, D., Smith, K. E. and Egdell, R.G., Influence of shallow core-level hybridization on the electronic structure of post-transition-metal oxides studied using soft x-ray emission and absorption, Physical Review B: Condensed Matter and Materials Physics, 68, (16), 2003, p165104 - 1:165104-9 Journal Article, 2003

McGuinness, C., Fu, D., Downes, J. E., Smith, K. E., Hughes, G. and Roche J., Electronic structure of thin film silicon oxynitrides measured using soft x-ray emission and absorption, Journal of Applied Physics, 94, (6), 2003, p3919 - 3922 Journal Article, 2003

Smith, K. E., McGuinness, C., Downes, J. E., Ryan, P., Fu, D., Hulbert, S.L., Honig, J.M. and Egdell, R.G., Soft x-ray emission and resonant inelastic x-ray scattering studies of transition metal oxides, Materials Research Society Symposium Proceedings, Boston, USA, December 2002, 755, Materials Research Society, 2003, ppDD1.1.1 - DD1.1.10 Conference Paper, 2003

C. McGuinness, J. E. Downes, P. Ryan, K. E. Smith, D. Doppalapudi and T. D. Moustakas, X-ray spectroscopic studies of the bulk electronic structure of InxGa1-xN alloys, Materials Research Society Symposium Proceedings, Boston, USA, December 2002, 743, Materials Research Society , 2003, ppL10.11.1 - L10.11.6 Conference Paper, 2003

Ryan, P., McGuinness, C., Downes, J. E., Smith, K. E., Doppalapudi D. and Moustakas, T. D., Band-gap evolution, hybridization and thermal stability of In1-xGaxN alloys measured by soft x-ray emission and absorption, Physical Review B: Condensed Matter and Materials Physics, 65, 2002, p205201 - 1:205201-7 Journal Article, 2002

Kilbane, D., Cummings, A., McGuinness, C., Murphy N. and O'Sullivan G., 4f collapse, level density inflation and the emergence of 'compound-like' atomic states in rare earth ions, Journal of Physics B: Atomic, Molecular and Optical Physics, 35, (2), 2002, p309 - 321 Journal Article, 2002

Schmitt, T., Duda, L.-C., Augustsson, A., Guo, J.-H., Nordgren, J., Downes, J. E., McGuinness, C., Smith, K. E., Dhalenne, G., Revcolevschi, A., Klemm, M. and Horn S, Resonant soft x-ray emission spectroscopy of V2O3, VO2 and NaV2O5, Surface Review Letters, 9, (2), 2002, p1369 - 1374 Journal Article, 2002

Neogi, A., Martins, M., McGuinness, C., O'Sullivan, G., Kennedy, E. T., Mosnier, J. P., Van Kampen P. and Costello, J. T., Vacuum-ultraviolet absorption spectrum of the Rb2+ ion in a laser generated plasma, Journal of Physics B: Atomic, Molecular and Optical Physics, 35, (5), 2002, p1329 - 1335 Journal Article, 2002

Neogi, A., Kennedy, E.T., Mosnier, J.-P., van Kampen, P., Costello, J.T., McGuinness, C. and O'Sullivan, G., Vacuum-UV absorption spectrum of the Rb+ ion in a laser generated plasma, Journal of Physics B: Atomic, Molecular and Optical Physics, 34, (20), 2001, p651 - L656 Journal Article, 2001

Cummings, A. , McGuinness, C., O'Sullivan, G., Costello, J.T., Mosnier, J.P., Kennedy, E.T., Wave-function collapse with increasing ionization: 4d photoabsorption of Cs through Cs4+, Physical Review A: Atomic, Molecular and Optical Physics, 63, 2001, p022702 - 2711 Journal Article, 2001

Guinness, C. Mc, Smith, K E., Butorin, S.M., Guo, J. H., Nordgren, J., Vogt, T., Schneider, G., Reilly, J., Tu, J. J., Johnson, P. D. and Shuh, D. K., High-resolution X-ray emission and absorption study of the B 2p valence band electronic structure of MgB2, EuroPhysics Letters, 56, (1), 2001, p112 - 118 Journal Article, 2001

Ryan, P., Chao, Y.C., Downes, J.E., McGuinness, C., Smith, K.E., Sampath, A.V., Moustakas, T.D., Surface electronic structure of p-type GaN(0001), Surface Science Letters, 467, (1-3), 2000, pL827 - L833 Journal Article, 2000

Duda, L.C., Downes, J.E., McGuinness, C., Schmitt, T., Augustsson, A., Smith, K.E., Dhalenne G. and Revcolevschi, A., Bandlike and excitonic states of oxygen in CuGeO3: Observation using polarized resonant soft x-ray emission spectroscopy, Physical Review B: Condensed Matter and Materials Physics, 61, ( 6), 2000, p4186 - 4189 Journal Article, 2000

The evolution of 4d photoabsorption in Sb with increasing ionization, D'Arcy, R., Costello, J. T., Kennedy, E. T., McGuinness, C., Mosnier, J. P. and O'Sullivan, G., Journal of Physics B: Atomic, Molecular and Optical Physics, 33, (7), 2000, p1383 - 1401 Journal Article, 2000

McGuinness, C., Martins, M., van Kampen, P. Hirsch, J., Kennedy, E.T., Mosnier, J.P., Whitty, W.W. and Costello, J.T., Vacuum UV absorption spectrum of a chromium laser produced plasma: 3p subshell photoabsorption by Cr2+ atoms, Journal of Physics B: Atomic, Molecular and Optical Physics, 33, (22), 2000, p5077 - 5090 Journal Article, 2000

Meighan, O., Danson, C., Dardis, L., Lewis, C. L. S., MacPhee, A., McGuinness, C., O'Rourke, R., Shaikh, W., Turcu, I. C. E., Costello, J. T., Application of a picosecond laser plasma continuum light source to a dual laser-plasma photoabsorption experiment, Journal of Physics B: Atomic, Molecular and Optical Physics, 33, (6), 2000, p1159 - 1168 Journal Article, 2000

O'Sullivan, G., Carroll, P. K., Dunne, P., Faulkner, R., McGuinness C. and Murphy N., Supercomplex spectra and continuum emission from rare-earth ions; Sm- a case study, Journal of Physics B: Atomic, Molecular and Optical Physics, 32, (8), 1999, p1893 - 1922 Journal Article, 1999

Obst,B., Benten, W., von dem Borne, A., Costello, J.T., Dardis, L., Gerth, Ch., Glatzel, P., Gray, A., Hansen, J. E., Meighan, O., Kennedy, E.T., McGuinness, C., Sonntag, B.F., Verweyen, A., Wernet Ph. and Zimmerman P., High resolution spectroscopy of 2p6-2p53d resonantly excited atomic Ca, Journal of Electron Spectroscopy and Related Phenomena, 101-103, 1999, p39 - 42 Journal Article, 1999

McGuinness, C., Martins, M., Wernet, Ph., Sonntag, B. F., van Kampen, P., Mosnier, J. P., Kennedy, E. T. and Costello J.T., Metastable state contributions to the measured 3p photoabsorption spectrum of Cr+ ions in a laser produced plasma, Journal of Physics B: Atomic, Molecular and Optical Physics, 32, (20), 1999, pL583 - L591 Journal Article, 1999

D'Arcy, R., Costello, J. T., McGuinness, C. and O'Sullivan, G. , Discrete structure in the 4d photoabsorption spectrum of antimony and its ions, Journal of Physics B: Atomic Molecular and Optical Physics, 32, (20), 1999, p4859 - 4876 Journal Article, 1999

Murphy, N., Costello, J. T., McGuinness, C., Kennedy, E. T., Mosnier, J.-P., Weinmann, B. and. O'Sullivan, G, Discrete structure in the 4d photoabsorption spectrum of tellurium and its ions, Journal of Physics B: Atomic, Molecular and Optical Physics, 32, (15), 1999, p3905 - 3922 Journal Article, 1999

McGuinness, C. and Murphy, N., The role of compound states in the continuum emission from moderately ionized rare-earth plasmas , New Directions in Atomic Physics [Proc. Int. Conf.], New York, edited by C. Whelan, R. M. Dreizler, J. H. Macek, H. R. J. Walters , Kluwer Academic/Plenum Press, 1999, pp191 - 195 Conference Paper, 1999

Kennedy, E.T., Costello, J.T., Gray, A., McGuinness, C., Mosnier J.P. and van Kampen P. , New dual laser plasma investigations of inner-shell excitations, Journal of Electron Spectroscopy and Related Phenomena, 101-103,, 1999, p161 - 166 Journal Article, 1999

Costello, J. T., Kennedy, E. T., Mosnier, J.-P., Sayyad, M. H. and McGuinness C., Extreme-UV photoabsorption spectrum of a laser produced silicon plasma: evidence for metastable Si* ions, Journal of Physics B: Atomic, Molecular and Optical Physics, 31, (Number 13), 1998, p547 - 552 Journal Article, 1998

MCGUINNESS, C, K-SHELL PHOTOIONIZATION CROSS SECTION OF CARBON IV, JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS, 30, 1997, p59 - 67 Journal Article, 1997

Berg, L.-E., Ekvall, K., Hishikawa, A., Kelly, S. and McGuinness, C., Laser Spectroscopy of SrH. Time-resolved measurements of the A 2Pi State, Chemical Physics Letters, 255, (Numbers 4-6), 1996, p419 - 424 Journal Article, 1996

O'Sullivan, G., Dunne, P., Cummings, A., Costello, J. T., Kennedy, E. T., McGuinness, C., O'Reilly, F., van Kampen P. and Weinmann B., Inner Shell Photoabsorption of Ions with the Dual Laser Produced Plasma (DLP) method, Autoionization Phenomena in Atoms, 5th International Workshop, Dubna, Russia, 1995, (ISBN 077(02)-96), Moscow University Press, 1996 Conference Paper, 1996

MCGUINNESS, C, OSULLIVAN, G, CARROLL, PK, AUDLEY, D, MANSFIELD, MWD, 3D ABSORPTION-SPECTRA OF SR-I THROUGH SR-IV, PHYSICAL REVIEW A, 51, 1995, p2053 - 2062 Journal Article, 1995

OSULLIVAN, G, CARROLL, PK, CONWAY, J, DUNNE, P, FAULKNER, R, MCCORMACK, T, MCGUINNESS, C, VANKAMPEN, P, WEINMANN, B, EXTREME-ULTRAVIOLET CONTINUUM EMISSION FROM LASER-GENERATED PLASMAS AND APPLICATIONS TO SPECTROSCOPY, OPTICAL ENGINEERING, 33, 1994, p3993 - 3998 Journal Article, 1994

Research Expertise

Description

I am interested in the application of x-ray spectroscopic techniques to the investigation of the electronic structure of materials. Materials studied range from organic semiconductors, wide bandgap nitride semiconductors, wide band gap oxide semiconductors, doped magnetic semiconductors, transition metal oxides and highly correlated electron systems exhibiting metal-insulator transitions and superconductivity as well as capped magnetic atomic nanowires.
More specifically my current research has a number of distinct strands. The first and second strands of research are the measuring of site-specific, symmetry-, state- and polarisation-dependent electronic structure of transition metal oxides, specifically the study of chemical bonding in rutile type transition metal oxides. and secondly the investigation of electronic structure in organic molecular semiconductors such as the phthalocyanine family of compounds.
For both of these strands I am also interested in the simulation of the electronic structure of these materials and the RXES and XAS via density-functional theory (DFT) methods employing Wien2K and StoBe codes; as well as atomic-multiplet methods for resonant inelastic x-ray scattering (RIXS);
The third strand of my research concerns the magnetic behaviour of low-dimensional atomic nanowires; the growth of low-dimensional several-atom-width nanowires on stepped vivinal single crystal metal surfaces and their characterisation by x-ray magnetic circular dichroism (XMCD), element-specific hysteresis loops and magneto-optic spectroscopies.
An earlier strand was the investigation of electronic structure of doped magnetic semiconductor materials.
These investigations all use high-brightness synchrotron x-ray sources such as MAX-lab (Swedish National Synchrotron facility), the NSLS (National Synchrotron Light Source, New York), the ALS (Advanced Light Source, California) and the SLS (Swiss Light Source) and ELettra (Italy). The techniques used are soft x-ray absorption spectroscopy (XAS), soft x-ray emission spectroscopy (XES), soft x-ray photoemission spectroscopy (XPS) and x-ray magnetic circular dichroism (XMCD). These techniques reveal detailed information about the conduction band structure, the valence band structure and the core-level structure of the material respectively. Further, through the use of resonant soft x-ray emission (RXES) the low-energy electronic excitations in a material can be directly probed leading to a resonant inelastic x-ray scattering (RIXS) spectrum, or chemical site dependent XES spectra can be obtained, particularly in the case of organic compounds.

Projects

  • Title
    • Novel element-selective symmetry, polarisation and state resolved investigations of chemical bonding
  • Summary
    • No topic is more fundamental to Chemistry than the nature of the chemical bond. In crystalline solids, the chemical bond gives rise to the electronic bandstructure of the material, this then determines whether the material is a metal, semiconductor, semi-metal, etc.; it determines the optical characteristics, the transport properties and the usefulness of any given crystalline solid. Novel x-ray spectroscopic techniques are now available to probe the electronic structure of crystalline solids, element-by-element and even state-by-state. These synchrotron radiation based methods will be applied to a particular class of crystalline solids to study more fully their basic electronic structure. The electronic structure of a class of crystalline solids will be investigated through a novel application of polarisation dependent synchrotron radiation based resonant soft x-ray emission spectroscopy and x-ray absorption spectroscopies to obtain element specific, symmetry and state selective measurements of the occupied partial density of states or occupied molecular orbitals of these solids. Systematic investigations of the chemical bonding in these rutile systems can thus be carried out and compared to electronic bandstructure calculations. Opportunities then exist to examine the bonding within these systems to alternative transition metals substitutionally doped onto the cation sites in these rutile systems. This project is in collaboration with Prof. Graeme Watson of the School of Chemistry and Prof. Russell Egdell, of the Chemistry Department, University of Oxford.
  • Funding Agency
    • Science Foundation Ireland
  • Date From
    • September 2007
  • Date To
    • August 2010
  • Title
    • X-ray magnetic dichroism of nanoscale magnetism in atomic wires protected by capping layers
  • Summary
    • Progress in ICT is driven by making electronic and magnetic devices with ever smaller active regions producing faster, more efficient devices. Single atomic wires of cobalt, possessing unusual magnetic properties, have been successfully grown on single crystal platinum surfaces. To be useful, these nanowires must be capped by ultra-thin films protecting them from contamination. The interfacial region formed by capping these nanoscale magnetic structures can enhance their magnetic properties, as measured by optical laser-interface interactions. These enhanced magnetic properties will be studied by x-ray based magnetic-spectroscopic imaging techniques and will allow for magnetic tuning of devices based on these wires. Atomic wires of cobalt, possessing unusual magnetic properties, have been successfully grown on platinum single crystal surfaces but, to be useful, such nanowires must be capped by ultra-thin films to protect them from contamination. The interfacial region formed by capping will affect the properties of these nanoscale magnetic structures; for certain capping layers and thicknesses enhanced Curie temperatures are expected. X-ray magnetic circular dichroism spectromicroscopy will be used to probe the magnetisation of these atomic wires on an element and electronic orbital specific basis, to complement and extend new non-linear magneto-optic studies of the same advanced materials. This project is in collaboration with John McGilp of the School of Physics
  • Funding Agency
    • Science Foundation Ireland
  • Date From
    • September 2007
  • Date To
    • August 2010
  • Title
    • Synchrotron X-ray Spectroscopic Investigations of Electronic Structure in Organic Semiconductors
  • Summary
    • Organic molecular semiconductor materials are of increasing technological importance. Ultrathin pure films of organic molecular semiconductors can be created by organic molecular beam deposition. The electronic structure of organic molecular semiconductors is generally studied by photoemission spectroscopy, especially using synchrotron radiation. Additionally, synchrotron based soft x-ray emission spectroscopy and its resonant counterpart provides another powerful investigative tool. It is proposed to combine these two regimes in a multi-technique, multi-theme investigation of the metal-phthalocyanine family of organic semiconductors. The themes include, energetics, beam damage, growth modes and interfacial reaction/interaction. Specific attention is paid to a comparison of electron-emission and photon-absorption/emission methods. This project is in collaborations with Prof. I. T. McGovern of the School of Physics.
  • Funding Agency
    • Science Foundation Ireland
  • Date From
    • October 2004
  • Date To
    • October 2007
  • Title
    • Soft x-ray spectroscopic investigations of dilute magnetic semiconductors
  • Summary
    • Dilute magnetic semiconductor (DMS) materials for use in functional room temperature magnetic semiconductor devices are being actively developed. Detailed knowledge of their electronic and magnetic structure is urgently needed. This can be obtained through the use of soft x-ray synchrotron radiation based spectroscopic techniques which are especially useful due to their elemental selectivity. The proposal seeks to apply these techniques to a number of DMS materials, specifically transition metal doped semiconductor oxides and nitrides such as Co-doped ZnO, Co-doped SnO2 and Mn-doped GaN and AlN. Thin films of these DMS materials are being grown by pulsed laser deposition. The quality and observed ferromagnetic moments of these films are critically sensitive to growth conditions during deposition, as is the observed electronic structure. In Co-doped ZnO these phenomena, including magnetism, are directly linked to oxygen vacancies. This can be verified by studying their electronic structure by element-specific soft x-ray spectroscopy. Correlation between observed electronic structure, measured magnetic moment & growth conditions will give insight into producing better thin film ferromagnetic semiconductors. Further, the application of these techniques may help address the question of the detailed physical origin of magnetism in these dilute magnetic semiconductors, a matter of some controversy.
  • Funding Agency
    • Enterprise Ireland
  • Date From
    • 01-05-2006
  • Date To
    • 30-04-2007
  • Title
    • Soft x-ray spectroscopic investigations of transition metal oxide and nitride magnetic semiconductors
  • Summary
    • Candidate materials for functional room temperature magnetic semiconductor devices are currently being actively developed and detailed knowledge of the electronic and magnetic structure of these candidate materials is needed. This information can be obtained through the use of spectroscopic techniques where synchrotron radiation based techniques are especially useful due to their elemental selectivity. This proposed collaboration seeks to apply these synchrotron radiation based techniques to a number of these materials, specifically transition metal doped semiconductor oxides such as Co-doped ZnO and Co-doped SnO2. Two other materials, HfO2 and CaB6, will also be targeted as thin films of these materials unexpectedly exhibit magnetic behaviour even though nominally they are d0 materials. The techniques applied to investigate these materials will be soft x-ray emission spectroscopy, x-ray absorption spectroscopy and x-ray photoemission spectroscopy and their resonant counterparts to elucidate the electronic structure. It is anticipated that x-ray magnetic circular dichroism will also be applied to measure the spin and orbital moments of the constituent elements within the materials. Information obtained from such measurements will help confirm theoretical models and also elucidate current questions regarding the roles of dopants and non-magnetic elements in their magnetic behaviour. This project is a collaborative investigation with Prof. K. E. Smith of Boston University.
  • Funding Agency
    • Enterprise Ireland
  • Date From
    • June 2005
  • Date To
    • April 2006
  • Title
    • Soft x-ray emission studies of transition metal oxides and organic semiconductors
  • Summary
    • We propose to use synchrotron radiation based soft x-ray emission (SXE) spectroscopy to investigate the valence band electronic structure of two materials: Li2CuO2 and copper-phthalocyanine (Cu-Pc). The transition metal oxide, Li2CuO2, is an edge-sharing 1D chain compound, with many properties in common with other Cu-O compounds. These systems exhibit low energy electronic excitations in which there is currently great interest. Their excitation spectrum can be probed through application of resonant SXE to obtain the resonant inelastic x-ray scattering spectrum revealing d-d and Zhang-Rice singlet excitations. This can provide more information on Zhang-Rice singlets which are an important exchange mechanism within Cu-O systems. Secondly, application of the techniques of resonant SXE and soft x-ray absorption to organic semiconductor systems can yield detailed information on their highest occupied (HOMO) and lowest unoccupied (LUMO) molecular orbitals respectively. Fundamental information concerning the HOMO and LUMO of organic semiconductors is often either absent or incomplete and yet they determine the usefulness of a given material as an organic based electronic device. Undoped and doped Cu-Pc with other phthalocyanine organic semiconductors will be studied by this programme to provide such information. This is a collaboration with Prof. K. E. Smith of Boston University
  • Funding Agency
    • Enterprise Ireland
  • Date From
    • July 2004
  • Date To
    • May 2005

Keywords

Condensed Matter; Experimental Physics; Magnetism and spin electronics; Molecular electronics; Organic Coatings; PHOTOELECTRON-SPECTROSCOPY; Resonant Inelastic X-ray Scattering; Solid State Physics; Spectroscopy; Surface and interface physics; Surface Physics; Surface Science; Synchrotron Radiation; Theory and computational physics; Thin Film, Technology and Applications; Vacuum Science; X-ray Emission Spectroscopy; X-RAY FLUORESCENCE; X-ray Magnetic Circular Dichroism; X-RAY PHOTOEMISSION; X-Ray Spectroscopy; X-RAY-ABSORPTION; X-RAY-SCATTERING; XANES; XPS; ZNO FILMS

Recognition

Representations

Irish user representative on the European Synchrotron Users Organisation (ESUO). November 2010

Awards and Honours

European Presidency Postdoctoral Fellowship

Nevin Medal - Experimental Physics, UCD

Memberships

Institute of Physics July 2006 – present

American Physical Society – present