3,851 research outputs found
Buffer-Enhanced Electrical-Pulse-Induced-Resistive Memory Effect in Thin Film Perovskites
A multilayer perovskite thin film resistive memory device has been developed
comprised of: a Pr0.7Ca0.3MnO3 (PCMO) perovskite oxide epitaxial layer on a
YBCO bottom thin film electrode; a thin yttria stabilized zirconia (YSZ) buffer
layer grown on the PCMO layer, and a gold thin film top electrode. The
multi-layer thin film lattice structure has been characterized by XRD and TEM
analyses showing a high quality heterostructure. I-AFM analysis indicated nano
granular conductivity distributed uniformly throughout the PCMO film surface.
With the addition of the YSZ buffer layer, the pulse voltage needed to switch
the device is significantly reduced and the resistance-switching ratio is
increased compared to a non-buffered resistance memory device, which is very
important for the device fabrication. The magnetic field effect on the
multilayer structure resistance at various temperatures shows CMR behavior for
both high and low resistance states implying a bulk material component to the
switch behavior.Comment: 16 pages, 4 figure
Two-dimensional hourglass Weyl nodal loop in monolayer Pb(ClO) and Sr(ClO)
The hourglass fermions in solid-state materials have been attracting
significant interest recently. However, realistic two-dimensional (2D)
materials with hourglass-shaped band structures are still very scarce. Here,
through the first-principles calculations, we identify the monolayer
Pb(ClO) and Sr(ClO) materials as the new realistic
materials platform to realize 2D hourglass Weyl nodal loop. We show that these
monolayer materials possess an hourglass Weyl nodal loop circling around the
point and Weyl nodal line on the Brillouin zone (BZ) boundary in the
absence of spin-orbit coupling (SOC). Through the symmetry analysis, we
demonstrate that the hourglass Weyl nodal loop and Weyl nodal line are
protected by the nonsymmorphic symmetries, and are robust under the biaxial
strains. When we include the SOC, a tiny gap will be opened in the hourglass
nodal loop and nodal line, and the nodal line can be transformed into the
spin-orbit Dirac points. Our results provide a new realistic material platform
for studying the intriguing physics associated with the 2D hourglass Weyl nodal
loop and spin-orbit Dirac points.Comment: 10 pages, 7 figures, Accepted for publication in New Journal of
Physic
Recommended from our members
Pollinator limitation causes sexual reproductive failure in ex situ populations of self-compatible Iris ensata
- …