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Research Interests
Professor Eskildsen
is interested in studies of superconductivity, especially in the
vortices induced in type-II superconductors by an applied magnetic
field. Such vortices consist of a core region in which supercondcutivity
is suppressed. Outside the core, the superconducting state recovers
over a characteristic lengthscale - the coherence length. Furthermore,
supercurrents circulating around the vortex screens the magnetic
field and confines it to the vicinity of the vortex. The screening
length, which is usually called the penetration depth, is the second
characteristic lengthscale of a superconductor.
Two complimentary experimental techniques are used to study the
vortices: The first is a low-temperature scanning tunneling microscope
(STM) capable of measuring the quasiparticle density of states or
spectrum, and hence distinguish between the normal cores and the
surrounding superconducting regions on an atomic scale. This so-called
scanning tunneling spectroscopy (STS) allows a direct imaging of
the vortices. Secondly, since the vortices in general arrange themselves
in an ordered array leading to a periodic magnetic field modulation,
the structure and symmetry of this vortex-lattice can be studies
by small-angle magnetic neutron scattering (SANS). Such experiments
are performed at large national or international facilities such
as for example the Institut Laue-Langevin (Grenoble, France).
Selected Publications
"Hexagonal and Square Flux Line Lattices in CeCoIn5," M.R. Eskildsen,
C.D. Dewhurst, B.W. Hoogenboom, C. Petrovic and P.C. Canfield,
Phys. Rev. Lett. 90, 187001 (2003).
"Scanning Tunneling Spectroscopy on Single
Crystal MgB2," M.R. Eskildsen, M.
Kugler, G. Levy, S. Tanaka, J. Jun, S.M. Kazakov, J. Karpinski
and Ø. Fischer, Physica C 385, 169-176 (2003).
"Vortex Imaging in the Band of Magnesium Diboride," M.R. Eskildsen, M.
Kugler, S. Tanaka, J. Jun, S.M. Kazakov, J. Karpinski and Ø.
Fischer, Phys.
Rev. Lett. 89, 187003 (2002).
"Interdependence of Magnetism and
Superconductivity in the Borocarbide TmNi2B2C," K. Nørgaard,
M.R. Eskildsen, N.H. Andersen, J. Jensen, P. Hedegård, S.N. Klausen and P.C. Canfield, Phys. Rev. Lett. 84, 4982-4985 (2000).
"Intertwined symmetry of the magnetic
modulation and the flux line lattice in the superconducting state
of TmNi2B2C," M.R. Eskildsen, K.
Harada, P.L. Gammel, A.B. Abrahamsen, N.H. Andersen, G. Ernst,
A.P. Ramirez, D.J. Bishop, K. Mortensen, D.R. Naugle, K.D.D.
Rathnayaka and P.C. Canfield, Nature 393, 242-245 (1998).
"Observation of a Field-Driven Structural
Phase Transition in the Flux Line Lattice in ErNi2B2C," M.R. Eskildsen, P.L. Gammel, B.P. Barber, U. Yaron, A.P. Ramirez, D.A. Huse, D.J. Bishop, C. Bolle, C.M. Lieber, S. Oxx, S. Sridhar, N.H. Andersen,
K. Mortensen and P.C. Canfield, Phys. Rev.
Lett. 78, 1968-1971 (1997).
Full curriculum vitae (pdf)
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