16 research outputs found
High-field irreversible moment reorientation in the antiferromagnet FeTe
Magnetization measurements have been performed on single-crystalline
FeTe in pulsed magnetic fields up to 53 T
and temperatures from 4.2 to 65 K. At K, a non-reversible reorientation
of the antiferromagnetic moments is observed at T as the pulsed
field is on the rise. No anomaly is observed at during the fall of the
field and, as long as the temperature is unchanged, during both rises and falls
of additional field pulses. The transition at is reactivated if the
sample is warmed up above the N\'{e}el temperature K and cooled
down again. The magnetic field-temperature phase diagram of FeTe in
is also investigated. We present the temperature
dependence of , as well as that of the antiferromagnetic-to-paramagnetic
borderline in temperatures above 40 K.Comment: 5 pages, 4 figure
A 31T split-pair pulsed magnet for single crystal x-ray diffraction at low temperature
We have developed a pulsed magnet system with panoramic access for
synchrotron x-ray diffraction in magnetic fields up to 31T and at low
temperature down to 1.5 K. The apparatus consists of a split-pair magnet, a
liquid nitrogen bath to cool the pulsed coil, and a helium cryostat allowing
sample temperatures from 1.5 up to 250 K. Using a 1.15MJ mobile generator,
magnetic field pulses of 60 ms length were generated in the magnet, with a rise
time of 16.5 ms and a repetition rate of 2 pulses/hour at 31 T. The setup was
validated for single crystal diffraction on the ESRF beamline ID06
Collective magnetism at multiferroic vortex domain walls
Topological defects have been playgrounds for many emergent phenomena in
complex matter such as superfluids, liquid crystals, and early universe.
Recently, vortex-like topological defects with six interlocked structural
antiphase and ferroelectric domains merging into a vortex core were revealed in
multiferroic hexagonal manganites. Numerous vortices are found to form an
intriguing self-organized network. Thus, it is imperative to find out the
magnetic nature of these vortices. Using cryogenic magnetic force microscopy,
we discovered unprecedented alternating net moments at domain walls around
vortices that can correlate over the entire vortex network in hexagonal ErMnO3
The collective nature of domain wall magnetism originates from the
uncompensated Er3+ moments and the correlated organization of the vortex
network. Furthermore, our proposed model indicates a fascinating phenomenon of
field-controllable spin chirality. Our results demonstrate a new route to
achieving magnetoelectric coupling at domain walls in single-phase
multiferroics, which may be harnessed for nanoscale multifunctional devices.Comment: 18 pages, 10 figure