QUIC-Fire_GUI
O5080 - QUIC-Fire GUI ment to run QUIC-Fire and other applications
Oliveto, Julia [Los Alamos National Laboratory]↗
Engineering topics
Nguyen, Quynh
Publications and source records attributed to Nguyen, Quynh.
Observation of time-reversal symmetry breaking in the band structure of altermagnetic RuO 2
Altermagnets are an emerging elementary class of collinear magnets. Unlike ferromagnets, their distinct crystal symmetries inhibit magnetization while, unlike antiferromagnets, they promote strong spin polarization in the band structure. The corresponding unconventional mechanism of time-reversal symmetry breaking without magnetization in the electronic spectra has been regarded as a primary signature of altermagnetism but has not been experimentally visualized to date. We directly observe strong time-reversal symmetry breaking in the band structure of altermagnetic RuO 2 by detecting magnetic circular dichroism in angle-resolved photoemission spectra. Our experimental results, supported by ab initio calculations, establish the microscopic electronic structure basis for a family of interesting phenomena and functionalities in fields ranging from topological matter to spintronics, which are based on the unconventional time-reversal symmetry breaking in altermagnets.
36 MATERIALS SCIENCE↗
Orbital-engineered anomalous Hall conductivity in stable full Heusler compounds: a pathway to optimized spintronics
Through high-throughput DFT, we explore AHC in 2904 full Heusler compounds, identifying several with superior AHC values, emphasizing the impact of valence electrons and electronegativity, and revealing their potential for spintronic applications.
Materials Science↗
Discovery of Giant, Non-saturating Thermopower in Topological Semimetal at Quantum Limit
Thermoelectrics are promising by directly generating electricity from waste heat. However, (sub-) room-temperature thermoelectrics have been a long-standing challenge, due to the vanishing electronic entropy at low temperature. Topological materials offer a new avenue for energy harvesting applications. Recent theories predicted that topological Weyl semimetals (WSMs) at the quantum limit can lead to a non-saturating longitudinal thermopower, as well as a quantized thermoelectric Hall conductivity approaching to a universal value. Here, we experimentally demonstrate the non-saturating thermopower and the signature of quantized thermoelectric Hall conductivity in WSM tantalum phosphide (TaP). An ultrahigh longitudinal thermopower Sxx = 1.1x10 3 muV/K, along with a power factor ~500 muW/cm/K 2 , are observed ~40K. Moreover, the thermoelectric Hall conductivity develops a plateau at high-fields and low temperatures, which further collapses onto a single curve determined by universal constants. Our work highlights the unique WSM electronic structure and topological protection of Weyl nodes toward low-temperature energy harvesting applications.
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗