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At least 541 records · Page 30

La 2 ⁢O 3 ⁢Mn 2 ⁢Se 2 : A correlated insulating layered d-wave altermagnet

Altermagnets represent a new class of magnetic phases without net magnetization, invariant under a combination of rotation and time reversal. Unlike conventional collinear antiferromagnets (AFM), altermagnets could lead to new correlated states and important material properties deriving from their nonrelativistic spin-split band structure. Indeed, they serve as the magnetic analogue of unconventional superconductors and can yield spin-polarized electrical currents in the absence of external magnetic fields, making them promising candidates for next-generation spintronics. Here, we report altermagnetism in the correlated insulator, magnetically ordered tetragonal oxychalcogenide, L⁢a 2 ⁢O 3⁢ M⁢n 2 ⁢S⁢e 2 . Symmetry analysis reveals a 𝑑 𝑥 2 −𝑦 2 -wave-like spin-momentum locking arising from the M⁢n 2 ⁢O Lieb lattice, supported by density functional theory (DFT) calculations. Magnetic measurements confirm the AFM transition below ∼166K while neutron pair distribution function analysis reveals a 2D short-range magnetic order that persists above the Néel temperature. Single crystals are grown and characterized using x-ray diffraction, optical and electron microscopy, and micro-Raman spectroscopy to confirm the crystal structure, stoichiometry, and uniformity. Furthermore, our findings establish L⁢a 2⁢ O 3 ⁢M⁢n 2⁢ S⁢e 2 as a model altermagnetic system realized on a Lieb lattice.

36 MATERIALS SCIENCE↗

Capacity Expansion Planning for LA Basin: the Role of Energy Storage

The paper evaluates the deployment of energy storage to support equitable energy outcomes and the clean energy transition in the Los Angeles Basin (LAB). The deployment of energy storage is considered in a 10 zone capacity expansion planning model from 2022-2045. The model is based on the California Public Utility Commission’s 7 zone RESOLVE model but has been modified to give greater spatial granularity in the LAB area by addig 3 new zones representing the Eastern Los Angeles, Western Los Angeles and the El Nido subzones. Three different scenarios are studied in this work; a base case with no natural gas retirements in the LAB, and two cases exploring extreme natural gas retirements, where the 8GW of natural gas belonging to the LAB are retired by 2045. Study results indicate that storage can play a significant role in helping the LAB meeting its energy requirements. However, when considering extreme retirement scenarios, either new generation (such as solar) or capacity (such as new import capacity via transmission lines) will likely be needed to serve projected system loads.

Maloney, Patrick R.↗

Detonation Wave Profile (update of LA-UR-15-29498-rev1)

The Zel’dovich-von Neumann-Doering (ZND) profile of a detonation wave is derived. Two basic material properties are required: i. An equation of state (EOS) for a partly burned explosive; P(V, e, λ). ii. A burn rate for the reaction progress variable; d/dtλ = R(V, e, λ). For a steady planar detonation wave the reactive flow PDEs can be reduced to ODEs. The detonation wave profile can be determined from an ODE plus algebraic equations for points on the partly burned detonation loci with a specified wave speed. Furthermore, for the CJ detonation speed, the end of the reaction zone is sonic. A solution to the reactive flow equations can be constructed with a rarefaction wave following the detonation wave profile. This corresponds to an underdriven detonation wave, and the rarefaction is know as a Taylor wave.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗

Understanding Building Energy Use in Eau Claire, La Crosse, Rochester, and Wausau: Basic Building Stock Characterization

This report is part of a publication series that focuses on approximately 100 different local geographies, or "clusters." Each report provides commercial and multifamily building characteristic and energy data for a local geography, with the intention of helping policymakers at the city, county and state levels better understand building energy use. Specifically, this report breaks down the building stock in the counties shown in Figure 1 by building type, size, energy consumption, and emissions.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗