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  1. Abstract The SuperCDMS SNOLAB dark matter search experiment aims to be sensitive to energy depositions down to 𝒪(1 eV). This imposes requirements on the resolution, signal efficiency, and noise rejection of the trigger system. To accomplish this, the SuperCDMS level-1 trigger system is implemented in an FPGA on a custom PCB. A time-domain optimal filter algorithm realized as a finite impulse response filter provides a baseline resolution of 0.38 times the standard deviation of the noise, σ n , and a 99.9% trigger efficiency for signal amplitudes of 1.1 σ n in typical noise conditions. Embedded in a modular architecture, flexible trigger logic enables reliable triggering and vetoing in a dead-time-free manner for a variety of purposes and run conditions. The trigger architecture and performance are detailed in this article.
    Free, publicly-accessible full text available July 1, 2023
  2. Free, publicly-accessible full text available January 1, 2023
  3. Free, publicly-accessible full text available January 1, 2023
  4. Garoufallou, E ; Ovalle-Perandones, M.A. (Ed.)
    This paper introduces Helping Interdisciplinary Vocabulary Engineering for Materials Science (HIVE-4-MAT), an automatic linked data ontology application. The paper provides contextual background for materials science, shared ontology infrastructures, and knowledge extraction applications. HIVE-4-MAT's three key features are reviewed: 1) Vocabulary browsing, 2) Term search and selection, and 3) Knowledge Extraction/Indexing, as well as the basics of named entity recognition (NER). The discussion elaborates on the importance of ontology infrastructures and steps taken to enhance knowledge extraction. The conclusion highlights next steps surveying the ontology landscape, including NER work as a step toward relation extraction (RE), and support for better ontologies.
  5. Metamaterials represent a class of artificially engineered materials, which exhibit unprecedented properties enabled by their constituent subwavelength unit cells. The effective properties of metamaterials may be dynamically controlled by driving unit cells via different approaches, including photo-doping, electrical gating, or mechanical actuation. With such dynamical tuning mechanisms, the propagation modality of electromagnetic waves may be modulated to achieve functional devices for modulation, beam steering, focusing, and polarization control, among others. In addition, the perfect absorption and near field effect enabled by metamaterials may be used in electromagnetic detectors across the frequency spectrum. Microsystem technology provides a platform to achieve functional metamaterial devices by covering all requisite processes, including fabrication, packaging, and system integration. We report our progress in constructing functional devices by integrating metamaterials with microsystems technology and discuss remaining challenges and the future direction of metamaterial devices.
  6. Abstract A recent focus of quantum spin liquid (QSL) studies is how disorder/randomness in a QSL candidate affects its true magnetic ground state. The ultimate question is whether the QSL survives disorder or the disorder leads to a “spin-liquid-like” state, such as the proposed random-singlet (RS) state. Since disorder is a standard feature of most QSL candidates, this question represents a major challenge for QSL candidates. YbMgGaO 4 , a triangular lattice antiferromagnet with effective spin-1/2 Yb 3+ ions, is an ideal system to address this question, since it shows no long-range magnetic ordering with Mg/Ga site disorder. Despite the intensive study, it remains unresolved as to whether YbMgGaO 4 is a QSL or in the RS state. Here, through ultralow-temperature thermal conductivity and magnetic torque measurements, plus specific heat and DC magnetization data, we observed a residual κ 0 / T term and series of quantum spin state transitions in the zero temperature limit for YbMgGaO 4 . These observations strongly suggest that a QSL state with itinerant excitations and quantum spin fluctuations survives disorder in YbMgGaO 4 .
    Free, publicly-accessible full text available December 1, 2022