3 research outputs found
Template Synthesis of MoN Superconducting Nanowires
We have demonstrated a new facile method for the controllable synthesis of high quality single-phase MoN nanowires with Tc 10.5 K from Mo6S2I8 nanowires templates. The MoN nanowire diameters were controlled exclusively by the Mo6S2I8 nanowires template diameters, which were in the range between several tens and several hundreds of nanometers in this study. Furthermore, we have demonstrated that Ohmic contacts can be prepared on δ3-MoN nanowires with ion beam induced platinum deposition using an FIB, allowing detailed characterization of the superconducting and transport properties of MoN nanowires. In addition, we have demonstrated straightforward synthesis of porous δ3-MoN nanowires and nanotubes from MoS2 nanotubes. X-ray diffraction, scanning electron microscopy with wave dispersive analysis, transmission electron microscopy, four probe electrical transport measurements and SQUID were used to characterize the starting nanowires and nanotubes and the final products
ESR of MnO embedded in silica nanoporous matrices with different topologies
Electron spin resonance (ESR) experiments were performed with
antiferromagnetic MnO confined within a porous vycor-type glass and within
MCM-type channel matrices. A signal from confined MnO shows two components from
crystallized and amorphous MnO and depends on the pore topology. Crystallized
MnO within a porous glass shows a behavior having many similarities to the
bulk. In contrast with the bulk the strong ESR signal due to disordered
"surface" spins is observed below the magnetic transition. With the decrease of
channel diameter the fraction of amorphous MnO increases while the amount of
crystallized MnO decreases. The mutual influence of amorphous and crystalline
MnO is observed in the matrices with a larger channel diameter. In the matrices
with a smaller channel diameter the ESR signal mainly originates from amorphous
MnO and its behavior is typical for the highly disordered magnetic system.Comment: 7 pages pdf file, 5 figure
Ultrafast photoinduced reflectivity transients in
The temperature dependence of ultrafast photoinduced reflectivity transients
is reported in NdSrMnO thin film. The photoinduced
reflectivity shows a complex response with very different temperature
dependences on different timescales. The response on the sub-ps timescale
appears to be only weakly sensitive to the 270K-metal-insulator phase
transition. Below K the sub-ps response displays a two component
behavior indicating inhomogeneity of the film resulting from the substrate
induced strain. On the other hand, the slower response on the 10-100 ps
timescale is sensitive only to the metal-insulator phase transition and is in
agreement with some previously published results. The difference in the
temperature dependences of the responses on nanosecond and s timescales
indicates that thermal equilibrium between the different degrees of fredom is
established relatively slowly - on a nanosecond timescale