4 research outputs found
Multiple-magnon excitations shape the spin spectrum of cuprate parent compounds
Thanks to high resolution and polarization analysis, resonant inelastic x-ray
scattering (RIXS) magnetic spectra of La2CuO4, Sr2CuO2Cl2 and CaCuO2 reveal a
rich set of properties of the spin 1/2 antiferromagnetic square lattice of
cuprates. The leading single-magnon peak energy dispersion is in excellent
agreement with the corresponding inelastic neutron scattering measurements.
However, the RIXS data unveil an asymmetric lineshape possibly due to odd
higher order terms. Moreover, a sharp bimagnon feature emerges from the
continuum at (1/2,0), coincident in energy with the bimagnon peak detected in
optical spectroscopy. These findings show that the inherently complex spin
spectra of cuprates, an exquisite manifestation of quantum magnetism, can be
effectively explored by exploiting the richness of RIXS cross sections.Comment: 7 pages, 3 figure
Discovery of Superconductivity and Electron-Phonon Drag in the Non-Centrosymmetric Semimetal LaRhGe
We present a comprehensive study of the non-centrosymmetric semimetal
LaRhGe. Our transport measurements reveal evidence for electron-hole
compensation at low temperatures, resulting in a large magnetoresistance of
3000% at 1.8 K and 14 T. The carrier concentration is on the order of
, higher than typical semimetals. We predict theoretically
the existence of Weyl nodal lines that are protected
by the tetragonal space group. We discover superconductivity for the first time
in this compound with a of 0.39(1) K and of
2.1(1) mT, with evidence from specific heat and transverse-field muon spin
relaxation (). LaRhGe is a weakly-coupled type-I
superconductor, and we find no evidence for time-reversal symmetry breaking in
our zero-field . We study the electrical transport in the normal
state and find an unusual dependence at low temperature while
Seebeck coefficient and thermal conductivity measurements reveal a peak in the
same temperature range. We conclude that the transport properties of LaRhGe
in its normal state are strongly influenced by electron-phonon interactions.
Furthermore, we examine the temperature dependent Raman spectra of LaRhGe
and find that the lifetime of the lowest energy phonon is dominated by
phonon-electron scattering instead of anharmonic decay
Recommended from our members
Photoinduced changes of reflectivity in single crystals of YBa2Cu3O6.5 (Ortho II)
We report measurements of the photoinduced change in reflectivity of an untwinned single crystal of YBa2Cu3O6.5 in the ortho II structure. The decay rate of the transient change in reflectivity is found to decrease rapidly with decreasing temperature and, below Tc, with decreasing laser intensity. We interpret the decay as a process of thermalization of antinodal quasiparticles, with a rate determined by inelastic scattering of quasiparticle pairs
Improving Accessibility to Intangible Cultural Heritage Preservation using Virtual Reality.
Presentations of virtual Cultural Heritage artifacts are often communicated via the medium of interactive digital storytelling. The synergy of a storied narrative embedded within a 3D virtual reconstruction context have high consumer appeal and edutainment value. We investigate if 360â—¦ videos presented through virtual reality further contribute to user immersion for the application of preserving Intangible Cultural Heritage. A case study then analyses whether conventional desktop media is significantly different than virtual reality as a medium for immersion in intangible heritage contexts. The case study describes bridge diving at Stari Most, the old bridge in Mostar Bosnia. This application aims to present and preserve the bridge diving tradition at this site. The project describes the site and history along with cultural connections, a series of quiz questions are presented after viewing all of the materials. Successful completion of the quiz allows a user to participate in a virtual bridge dive. The subjective evaluation provided evidence to suggest that our method is successful in preserving intangible heritage and communicating ideas in key areas of concern for this heritage that can be used to develop a preservation framework in the future. It was also possible to conclude that experience within the VR framework did not affect Effort Expectancy for the web application, but the same experience made a significant influence for the Performance Expectancy construct