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Zang, J.

Publications and source records attributed to Zang, J..

Nature of the ferromagnetic-antiferromagnetic transition in Y 1- x La x TiO 3

In this work, we explore the magnetically ordered ground state of the isovalently substituted Mott insulator Y 1- x La x TiO 3 for x≤ 0.3 via single-crystal growth, magnetometry, neutron diffraction, x-ray magnetic circular dichroism, muon spin rotation, and small-angle neutron scattering (SANS). We find that the decrease in the magnetic transition temperature on approaching the ferromagnetic-antiferromagnetic phase boundary at the La concentration xc ≈ 0.3 is accompanied by a strong suppression of both bulk and local ordered magnetic moments, along with a volume wise separation into magnetically ordered and paramagnetic regions. The thermal phase transition does not show conventional second-order behavior since neither a clear signature of dynamic critical behavior nor a power-law divergence of the magnetic correlation length is found for the studied substitution range; this finding becomes increasingly obvious with increasing La substitution. We find no evidence for a spin-glass phase. Finally, from SANS and magnetometry measurements, we discern a crossover from easy-axis to easy-plane magnetocrystalline anisotropy with increasing La substitution. These results indicate complex changes in magnetic structure upon approaching the phase boundary.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

OMI/TROPOMI Data Support from GES DISC

The NASA GES DISC has been the official archive center for data from the Ozone Monitoring Instrument (OMI) aboard NASA's Aura mission since 2004. In recent years, the GES DISC has been evolving and improving its data management and services in order to promote its data to be easily discovered and accessed, as well as to facilitate data "interoperability". This presentation will summarize metrics collected of OMI data usage and GES DISC data services. In order to support the recently released Sentinel-5P/TROPOMI data from ESA at the NASA GES DISC, a new End User License Agreement (EULA) has been implemented for users accessing these data from the GES DISC.

Johnson, J.↗