We are studying the electronic structures of new and advanced materials. We are using synchrotron radiation to perform soft x-ray emission and absorption spectroscopy of systems like biomaterials, superconductors and transition metal compounds.

Brett Leedahl

Brett Leedahl

Education

  • University of Saskatchewan
    Saskatoon, Saskatchewan
    B.Sc. (Honours) Physics
    May 2013
  • University of Saskatchewan
    Saskatoon, Saskatchewan
    M. Sc. Physics
    Started May 2013
  • University of Saskatchewan
    Saskatoon, Saskatchewan
    Ph. D. Physics
    Transferred from M. Sc. May 2014

brett.leedahl@usask.ca


Research Projects

Dilute Magnetic Semiconductors

Dilute magnetic semiconductors are standard semiconducting materials that have been doped with magnetic atoms to give them properties which can be utilized most notably in areas of spintronics and photocatalysis. My goal is to study these transition metal doped semiconductors experimentally and analyze the results using calculations based on the Anderson Impurity Model. This will provide an in depth understanding of how the dopants interact with the semiconductor to modify the electronic and magnetic properties.

Maximum Entropy Deconvolution

Broadening of spectra due to limitations in experimental equipment is generally the convolution of the true underlying signal and some point spread function, this function is roughly a Gaussian for spectrometer broadening. During my NSERC Undergraduate Summer Research position I developed an algorithm, based on the maximum entropy method in information theory, which can deconvolve experimental spectra that have been broadened due to the limitations in instrumental resolution. This purely mathematical approach allows a significant improvement of experimental resolution of spectroscopic data taken at synchrotrons with very low computational cost. This deconvolution algorithm is of particular interest to resonant X-ray emission and scattering techniques due to the broadening being dominated by instrumental factors rather than the more complicated lifetime broadening, which is due to quantum mechanical effects.

Awards

  • Saskatchewan Innovation and Opportunity Scholarship (2015)
  • Saskatchewan Innovation and Opportunity Scholarship (2014)
  • Department of Physics and Engineering Physics Scholarship (2013)
  • NSERC Undergraduate Summer Research Award (2012)
  • James F. Mathison Memorial Scholarship (2012)
  • Jennette Gertrude Traynor Award (2011)

Publications

  • B. Leedahl, A. V. Korolev, I. S. Zhidkov, S. L. Skornyakov, V. I. Anisimov, A. S. Belozerov, A. I. Kukharenko, E. Z. Kurmaev, V. I. Grokhovskii S. O. Cholakhd and A. Moewesa
    Searching for pure iron in nature: the Chelyabinsk meteorite
    RSC Advances, (6), 85844 (2016).

  • K. Bouras, G. Schmerber, D. Aureau, H. Rinnert, G. Ferblantier, T. Fix, S. Colis, P. Bazylewski, B. Leedahl, A. Etcheberry, G. S. Chang, A. Dinia and A. Slaoui
    Insight into photon conversion of Nd3+ doped low temperature grown p and n type tin oxide thin films
    RSC Advances, (6), 67157 (2016).

  • T. M. Tolhurst, B. Leedahl, J. L. Andrews, P. M. Marley, S. Banerjeeb and A. Moewes
    Contrasting 1D tunnel-structured and 2D layered polymorphs of V2O5: relating crystal structure and bonding to band gaps and electronic structure
    Journal of Physical Chemistry Chemical Physics, (18), 15798 (2016).

  • P.. Bazylewski, V. L. Nguyen, R. P.C. Bauer, A. H. Hunt, E. J. G. McDermott, B. Leedahl, A. I. Kukharenko, S. O. Cholakh, E. Z. Kurmaev, P. Blaha, A. Moewes, Y. H. Lee & G. S. Chang
    Selective Area Band Engineering of Graphene using Cobalt-Mediated Oxidation
    Scientific Reports, (5), 15380 (2015).

  • R. J. Green, T. Z. Regier, B. Leedahl, J. A. McLeod, X. H. Xu, G. S. Chang, E. Z. Kurmaev, and A. Moewes
    Adjacent Fe-Vacancy Interactions as the Origin of Room Temperature Ferromagnetism in (In1−xFex)2O3
    Physical Review Letters, (115), 167401 (2015).

  • B. Leedahl, D. A. Zatsepin, D. W. Boukhvalov, E. Z. Kurmaev, R. J. Green, I. S. Zhidkov, S. S. Kim, L. Cui, N. V. Gavrilov, S. O. Cholakh, and A. Moewes
    Study of the Structural Characteristics of 3d Metals Cr, Mn, Fe, Co, Ni, and Cu Implanted in ZnO and TiO2—Experiment and Theory
    Journal of Physical Chemistry C, (118), 28143 (2014).

  • B. Leedahl, D. A. Zatsepin, D. W. Boukhvalov, R. J. Green, J. A. McLeod, S. S. Kim, E. Z. Kurmaev, I. S. Zhidkov, N. V. Gavrilov, S. O. Cholakh, and A. Moewes,
    Structural defects induced by Fe-ion implantation in TiO2
    Journal of Applied Physics, (115), 053711 (2014).

  • J. A. McLeod, D. W. Boukhvalov, D. A. Zatsepin, R. J. Green, B. Leedahl, L. Cui, E. Z. Kurmaev, I. S. Zhidkov, L. Finkelstein, N. V. Gavrilov, S. O. Cholakh, and A. Moewes,
    Local structure of Fe impurity atoms in ZnO: bulk versus surface
    Journal of Physical Chemistry C (118), 5336-5345 (2014).