590 research outputs found
Local density of states and superconducting gap in the iron chalcogenide superconductor FeSeTe observed by scanning tunneling spectroscopy
We report on the first investigation of the quasiparticle local density of
states and superconducting gap in the iron chalcogenide superconductor
FeSeTe ( K). The surface of
a cleaved crystal revealed an atomic square lattice, superimposed on the
inhomogeneous background, with a lattice constant of \AA without any
reconstruction. Tunneling spectra measured at 4.2 K exhibit the superconducting
gap, which completely disappears at 18 K, with a magnitude of meV,
corresponding to .In stark contrast
to the cuprate superconductors, the value of the observed superconducting gap
is relatively homogeneous, following a sharp distribution with a small standard
deviation of 0.23 meV. Conversely, the normal-state local density of states
observed above shows spatial variation over a wide energy
range of more than 1 eV, probably due to the excess iron present in the
crystal.Comment: 4 pages, 5 figure
Novel slow dynamics of phase transition in the partially ordered frustrated magnet DyRu2Si2
DyRu2Si2 is a frustrated magnet to exhibit multiple magnetic phase transition
in zero and finite magnetic fields. We investigated and characterized the phase
transition between the partially-ordered antiferromagnetic phases at zero field
by ac susceptibility measurements. Detailed ac susceptibility measurements
reveal the novel critical dynamics of the phase transition; extremely slow
dynamics with the relaxation time in the order of 10-100 msec, speed-up of the
dynamics on cooling indicating its non-thermally activated origin and growing
of the ferromagnetic correlations towards the phase transition temperature. On
the basis of these findings, we propose the novel phase transition process,
namely, the spontaneous striped-arrangement of the precedently emergent
"belt-like" ferromagnetic spin texture.Comment: Accepted by JPSJ
URL:https://journals.jps.jp/doi/10.7566/JPSJ.92.09470
Doping Dependence of the in-Plane Transition in CoSnS
In CoSnS two transitions are observed, the main one to a
ferromagnetic state at K and the second one, involving in-plane
components at K. We follow their doping dependence as Sn is
replaced with In, which causes a reduction of and . Importantly,
both transitions follow the same doping dependence, indicating a single energy
scale involved with both processes.Comment: accepted as a short note in JPSJ; a continuation of work published in
arXiv:2211.01483 and https://doi.org/10.1103/PhysRevB.106.L18040
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