arXiv subjects

J. S. Claydon

Publications and source records attributed to J. S. Claydon.

3 recordsLinked to original sources

arXiv2023

Observation of Anomalous Josephson Effect in Nonequilibrium Andreev Interferometers

The first evidence of anomalous Josephson effect is reported in mesoscopic superconductor-normal metal-superconductor (SNS) junctions forming a crosslike Andreev Interferometer in the absence of magnetic and spin-orbit interactions normally required to break time-reversal and inversion symmetries. From conductance measurements of the out-of-equilibrium weak link, we determine a voltage-controlled spontaneous phase that resembles a $φ_0$-junction. The temperature and voltage dependences together with a dissipative term in the current-phase relation strongly suggest that the mechanism underlying the observed phenomenon relies on electron-hole asymmetries.

cond-mat.supr-con↗

arXiv2014

Observation of a temperature dependent asymmetry in the domain structure of a Pd doped FeRh epilayer

Using X-ray photoelectron emission microscopy we have observed the coexistence of ferromagnetic and antiferromagnetic phases in a (3 at.%)Pd-doped FeRh epilayer. By quantitatively analyzing the resultant images we observe that as the epilayer transforms there is a change in magnetic domain symmetry from predominantly twofold at lower temperatures through to an equally weighted combination of both four and twofold symmetries at higher temperature. It is postulated that the lowered symmetry Ising-like nematic phase resides at the near-surface of the epilayer. This behavior is different to that of undoped FeRh suggesting that the variation in symmetry is driven by the competing structural and electronic interactions in the nanoscale FeRh film coupled with the effect of the chemical doping disorder.

cond-mat.mtrl-sci↗

arXiv2008

Determination of the single-ion anisotropy energy in a S = 5/2 kagome antiferromagnet using X-ray absorption spectroscopy

We report x-ray absorption and x-ray linear dichroism measurements at the Fe L2,3 edges of the geometrically frustrated systems of potassium and hydronium iron jarosite. Comparison with simulated spectra, involving ligand-field multiplet calculations modelling the 3d-2p hybridization between the iron ion and the oxygen ligands, has yielded accurate estimates for the ligand metal-ion hybridization and the resulting single-ion crystal field anisotropy energy. Using this method we provide an experimentally verified scenario for the appearance of a single-ion anisotropy in this nominally high-spin 3d5 orbital singlet 6S system, which accounts for features of the spin-wave dispersion in the long-range ordered ground state of potassium iron jarosite.

cond-mat.str-el↗