@article{sun_wang_bloom_comstock_yang_mcconnell_clever_molitoris_lamont_cheng_et al._2024, title={Colossal anisotropic absorption of spin currents induced by chirality}, volume={10}, ISSN={["2375-2548"]}, DOI={10.1126/sciadv.adn3240}, abstractNote={The chiral induced spin selectivity (CISS) effect, in which the structural chirality of a material determines the preference for the transmission of electrons with one spin orientation over that of the other, is emerging as a design principle for creating next-generation spintronic devices. CISS implies that the spin preference of chiral structures persists upon injection of pure spin currents and can act as a spin analyzer without the need for a ferromagnet. Here, we report an anomalous spin current absorption in chiral metal oxides that manifests a colossal anisotropic nonlocal Gilbert damping with a maximum-to-minimum ratio of up to 1000%. A twofold symmetry of the damping is shown to result from differential spin transmission and backscattering that arise from chirality-induced spin splitting along the chiral axis. These studies reveal the rich interplay of chirality and spin dynamics and identify how chiral materials can be implemented to direct the transport of spin current.}, number={18}, journal={SCIENCE ADVANCES}, author={Sun, Rui and Wang, Ziqi and Bloom, Brian P. and Comstock, Andrew H. and Yang, Cong and McConnell, Aeron and Clever, Caleb and Molitoris, Mary and Lamont, Daniel and Cheng, Zhao-Hua and et al.}, year={2024}, month={May} }
 @article{xiong_christy_dong_comstock_sun_li_cahoon_yang_zhang_2024, title={Combinatorial split-ring and spiral metaresonator for efficient magnon-photon coupling}, volume={21}, ISSN={["2331-7019"]}, DOI={10.1103/PhysRevApplied.21.034034}, abstractNote={Developing hybrid materials and structures for electromagnetic wave engineering has been a promising route towards novel functionalities and tunabilities in many modern applications. Despite its established success in engineering optical light and terahertz waves, the implementation of metaresonators operating in the microwave band is still emerging, especially the implementation of metaresonators that allow on-chip integration and size miniaturization, which is crucial for developing hybrid quantum systems in the microwave band. In this work, we present a microwave metaresonator consisting of split-ring and spiral resonators, and implement it for the investigation of photon-magnon coupling for hybrid magnonic applications. We observe broadened bandwidth of the split-ring modes augmented by the additional spiral resonator, and, by coupling the modes to a magnetic sample, the resultant photon-magnon coupling can be significantly enhanced by more than tenfold. Our work suggests that combinatorial, hybrid microwave resonators may be a promising approach towards future development and implementation of photon-magnon coupling in hybrid magnonic systems.}, number={3}, journal={PHYSICAL REVIEW APPLIED}, author={Xiong, Yuzan and Christy, Andrew and Dong, Yun and Comstock, Andrew H. and Sun, Dali and Li, Yi and Cahoon, James F. and Yang, Binbin and Zhang, Wei}, year={2024}, month={Mar} }
 @article{montoya_grimley_aykol_ophus_sternlicht_savitzky_minor_torrisi_goedjen_chung_et al._2024, title={How the AI-assisted discovery and synthesis of a ternary oxide highlights capability gaps in materials science}, ISSN={["2041-6539"]}, DOI={10.1039/d3sc04823c}, abstractNote={Exploratory synthesis has been the main generator of new inorganic materials for decades. AI-assisted discovery is possible, but human-AI collaboration should be refined according to their respective strengths.}, journal={CHEMICAL SCIENCE}, author={Montoya, Joseph H. and Grimley, Carolyn and Aykol, Muratahan and Ophus, Colin and Sternlicht, Hadas and Savitzky, Benjamin H. and Minor, Andrew M. and Torrisi, Steven B. and Goedjen, Jackson and Chung, Ching-Chang and et al.}, year={2024}, month={Mar} }
 @article{sun_park_comstock_mcconnell_chen_zhang_beratan_you_hoffmann_yu_et al._2024, title={Inverse chirality-induced spin selectivity effect in chiral assemblies of <i>π</i>-conjugated polymers}, volume={3}, ISSN={["1476-4660"]}, DOI={10.1038/s41563-024-01838-8}, journal={NATURE MATERIALS}, author={Sun, Rui and Park, Kyung Sun and Comstock, Andrew H. and Mcconnell, Aeron and Chen, Yen-Chi and Zhang, Peng and Beratan, David and You, Wei and Hoffmann, Axel and Yu, Zhi-Gang and et al.}, year={2024}, month={Mar} }
 @article{yang_qiu_li_xue_liu_sun_yang_gai_wei_comstock_et al._2023, title={Anisotropic Nonlocal Damping in Ferromagnet/α -GeTe Bilayers Enabled by Splitting Energy Bands}, volume={131}, ISSN={["1079-7114"]}, DOI={10.1103/PhysRevLett.131.186703}, abstractNote={The understanding and manipulation of anisotropic Gilbert damping is crucial for both fundamental research and versatile engineering and optimization. Although several works on anisotropic damping have been reported, no direct relationship between the band structure and anisotropic damping was established. Here, we observed an anisotropic damping in Fe/GeTe manipulated by the symmetric band structures of GeTe via angle-resolved photoemission spectroscopy. Moreover, the anisotropic damping can be modified by the symmetry of band structures. Our Letter provides insightful understandings of the anisotropic Gilbert damping in ferromagnets interfaced with Rashba semiconductors and suggests the possibility of manipulating the Gilbert damping by band engineering.}, number={18}, journal={PHYSICAL REVIEW LETTERS}, author={Yang, Xu and Qiu, Liang and Li, Yan and Xue, Hao-Pu and Liu, Jia-Nan and Sun, Rui and Yang, Qing-Lin and Gai, Xue-Song and Wei, Yan-Sheng and Comstock, Andrew H. and et al.}, year={2023}, month={Nov} }
 @article{kim_vetter_yan_yang_wang_sun_yang_comstock_li_zhou_et al._2023, title={Chiral-phonon-activated spin Seebeck effect}, volume={2}, ISSN={["1476-4660"]}, url={http://dx.doi.org/10.1038/s41563-023-01473-9}, DOI={10.1038/s41563-023-01473-9}, abstractNote={Utilization of the interaction between spin and heat currents is the central focus of the field of spin caloritronics. Chiral phonons possessing angular momentum arising from the broken symmetry of a non-magnetic material create the potential for generating spin currents at room temperature in response to a thermal gradient, precluding the need for a ferromagnetic contact. Here we show the observation of spin currents generated by chiral phonons in a two-dimensional layered hybrid organic-inorganic perovskite implanted with chiral cations when subjected to a thermal gradient. The generated spin current shows a strong dependence on the chirality of the film and external magnetic fields, of which the coefficient is orders of magnitude larger than that produced by the reported spin Seebeck effect. Our findings indicate the potential of chiral phonons for spin caloritronic applications and offer a new route towards spin generation in the absence of magnetic materials.}, journal={NATURE MATERIALS}, publisher={Springer Science and Business Media LLC}, author={Kim, Kyunghoon and Vetter, Eric and Yan, Liang and Yang, Cong and Wang, Ziqi and Sun, Rui and Yang, Yu and Comstock, Andrew H. and Li, Xiao and Zhou, Jun and et al.}, year={2023}, month={Feb} }
 @article{xue_sun_yang_comstock_liu_ge_liu_wei_yang_gai_et al._2023, title={Dual Topology of Dirac Electron Transport and Photogalvanic Effect in Low-Dimensional Topological Insulator Superlattices}, volume={1}, ISSN={["1521-4095"]}, DOI={10.1002/adma.202208343}, abstractNote={Abstract}, journal={ADVANCED MATERIALS}, author={Xue, Hao-Pu and Sun, Rui and Yang, Xu and Comstock, Andrew and Liu, Yangrui and Ge, Binghui and Liu, Jia-Nan and Wei, Yan-Sheng and Yang, Qing-Lin and Gai, Xue-Song and et al.}, year={2023}, month={Jan} }
 @article{li_comstock_mcconnell_li_yun_sun_xu_2023, title={Giant interfacial spin Hall angle from Rashba-Edelstein effect revealed by the spin Hall Hanle process}, volume={108}, ISSN={["2469-9969"]}, url={https://doi.org/10.1103/PhysRevB.108.L241403}, DOI={10.1103/PhysRevB.108.L241403}, abstractNote={The Rashba-Edelstein effect (REE), which generates interfacial spin polarization and subsequent spin current, is a compelling spin-charge conversion mechanism for spintronics applications, since it is not limited by the elemental spin-orbit coupling. In this work, we demonstrate REE at Pt/ferroelectric interfaces using the recently elucidated spin-Hall Hanle effects (SHHE), in which a Larmor precession of spin polarization in a diffusion process from the interface manifest as magnetoresistance and Hall effect. We show that REE leads to a three-fold enhancement of the effective spin Hall angle in ferroelectric interface Pt/h-LuFeO3 compared to that of Pt /Al2O3, although the difference in the spin relaxation time is negligible. Modeling using SHHEs involving REE as an additional source of interfacial polarization suggests that REE can lead to an interfacial spin Hall angle (~0.3) that is one order of magnitude larger than the bulk value of Pt. Our results demonstrate that a ferroelectric interface can produce large spin-charge conversion and that SHHEs are a sensitive tool for characterizing interfacial spin transport properties.}, number={24}, journal={PHYSICAL REVIEW B}, author={Li, Jing and Comstock, Andrew H. and Mcconnell, Aeron and Li, Xin and Yun, Yu and Sun, Dali and Xu, Xiaoshan}, year={2023}, month={Dec} }
 @article{comstock_chou_wang_wang_song_sklenar_amassian_zhang_lu_liu_et al._2023, title={Hybrid magnonics in hybrid perovskite antiferromagnets}, volume={14}, ISSN={["2041-1723"]}, url={https://doi.org/10.1038/s41467-023-37505-w}, DOI={10.1038/s41467-023-37505-w}, abstractNote={Abstract}, number={1}, journal={NATURE COMMUNICATIONS}, author={Comstock, Andrew H. and Chou, Chung-Tao and Wang, Zhiyu and Wang, Tonghui and Song, Ruyi and Sklenar, Joseph and Amassian, Aram and Zhang, Wei and Lu, Haipeng and Liu, Luqiao and et al.}, year={2023}, month={Apr} }
 @article{li_draher_comstock_xiong_haque_easy_qian_polakovic_pearson_divan_et al._2023, title={Probing intrinsic magnon bandgap in a layered hybrid perovskite antiferromagnet by a superconducting resonator}, volume={5}, ISSN={["2643-1564"]}, DOI={10.1103/PhysRevResearch.5.043031}, abstractNote={Coherent interactions between different magnetic excitations can lead to formation of magnon band gaps and hybrid magnon modes, which can find their applications in magnonic devices and coherent information processing. In this work, we probe the intrinsic magnon band gap of a layered hybrid perovskite antiferromagnet by its strong coupling to a superconducting resonator. The pronounced temperature tunability of the magnon band gap location allows us to set the photon mode within the gap, leading to a reduction of effective magnon-photon coupling and eventually the disappearance of magnon-photon hybridization. When the resonator mode falls into the magnon band gap, the resonator damping rate increases due to the nonzero coupling to the detuned magnon mode. This allows for quantification of the magnon band gap using an analytical model. Our work brings new opportunities in controlling coherent information processing with quantum properties in complex magnetic materials.}, number={4}, journal={PHYSICAL REVIEW RESEARCH}, author={Li, Yi and Draher, Timothy and Comstock, Andrew H. and Xiong, Yuzan and Haque, Md Azimul and Easy, Elham and Qian, Jiangchao and Polakovic, Tomas and Pearson, John E. and Divan, Ralu and et al.}, year={2023}, month={Oct} }
 @article{frick_sridhar_khansari_comstock_norman_o'donnell_maggard_sun_dougherty_2023, title={Spreading resistance effects in tunneling spectroscopy of α-RuCl3 and Ir0.5Ru0.5Cl3}, volume={108}, ISSN={["2469-9969"]}, url={https://doi.org/10.1103/PhysRevB.108.245410}, DOI={10.1103/PhysRevB.108.245410}, abstractNote={The Mott insulating state is the progenitor of many interesting quantum phases of matter including the famous high-temperature superconductors and quantum spin liquids. A recent candidate for novel spin liquid phenomena is $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{RuCl}}_{3}$, a layered honeycomb Mott insulator whose electronic structure has been a source of mystery. In particular, scanning tunneling spectroscopy has indicated a Mott gap in $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{RuCl}}_{3}$ that is much lower than the 2-eV value observed in photoemission measurements. Here, we show that the origin of this discrepancy is a spreading resistance artifact associated with tunneling into highly resistive materials by comparing with prior experiments and numerical modeling. A similar phenomenon is also observed in a substitutional alloy, ${\mathrm{Ir}}_{0.5}{\mathrm{Ru}}_{0.5}{\mathrm{Cl}}_{3}$, that has a higher resistivity than the parent compound. While the tunneling measurements cannot be used to accurately measure the sample density of states for these materials, we can take advantage of the spreading resistance sensitivity to quantify the anisotropic resistivity of these layered materials and connect to previous macroscopic transport observations.}, number={24}, journal={PHYSICAL REVIEW B}, author={Frick, Jordan R. and Sridhar, Samanvitha and Khansari, Ario and Comstock, Andrew H. and Norman, Elizabeth and O'Donnell, Shaun and Maggard, Paul A. and Sun, Dali and Dougherty, Daniel B.}, year={2023}, month={Dec} }
 @article{negi_rodriguez_zhang_comstock_yang_sun_jiang_kumah_hu_liu_2023, title={Thickness-Dependent Thermal Conductivity and Phonon Mean Free Path Distribution in Single-Crystalline Barium Titanate}, volume={4}, ISSN={["2198-3844"]}, url={https://doi.org/10.1002/advs.202301273}, DOI={10.1002/advs.202301273}, abstractNote={Abstract}, journal={ADVANCED SCIENCE}, author={Negi, Ankit and Rodriguez, Alejandro and Zhang, Xuanyi and Comstock, Andrew H. H. and Yang, Cong and Sun, Dali and Jiang, Xiaoning and Kumah, Divine and Hu, Ming and Liu, Jun}, year={2023}, month={Apr} }
 @article{olson_somarajan_muszynski_comstock_hendrickson_scott_russell_acra_walker_bradshaw_2022, title={Automated Machine Learning Pipeline Framework for Classification of Pediatric Functional Nausea Using High-Resolution Electrogastrogram}, volume={69}, ISSN={["1558-2531"]}, DOI={10.1109/TBME.2021.3129175}, abstractNote={Objective: Pediatric functional nausea is challenging for patients to manage and for clinicians to treat since it lacks objective diagnosis and assessment. A data-driven non-invasive diagnostic screening tool that distinguishes the electro-pathophysiology of pediatric functional nausea from healthy controls would be an invaluable aid to support clinical decision-making in diagnosis and management of patient treatment methodology. The purpose of this paper is to present an innovative approach for objectively classifying pediatric functional nausea using cutaneous high-resolution electrogastrogram data. Methods: We present an Automated Electrogastrogram Data Analytics Pipeline framework and demonstrate its use in a 3x8 factorial design to identify an optimal classification model according to a defined objective function. Low-fidelity synthetic high-resolution electrogastrogram data were generated to validate outputs and determine SOBI-ICA noise reduction effectiveness. Results: A 10 parameter support vector machine binary classifier with a radial basis function kernel was selected as the overall top-performing model from a pool of over 1000 alternatives via maximization of an objective function. This resulted in a 91.6% test ROC AUC score. Conclusion: Using an automated machine learning pipeline approach to process high-resolution electrogastrogram data allows for clinically significant objective classification of pediatric functional nausea. Significance: To our knowledge, this is the first study to demonstrate clinically significant performance in the objective classification of pediatric nausea patients from healthy control subjects using experimental high-resolution electrogastrogram data. These results indicate a promising potential for high-resolution electrogastrography to serve as a data-driven screening tool for the objective diagnosis of pediatric functional nausea.}, number={5}, journal={IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING}, author={Olson, Joseph D. and Somarajan, Suseela and Muszynski, Nicole D. and Comstock, Andrew H. and Hendrickson, Kyra E. and Scott, Lauren and Russell, Alexandra and Acra, Sari A. and Walker, Lynn and Bradshaw, Leonard A.}, year={2022}, month={May}, pages={1717–1725} }
 @article{xue_wang_comstock_wang_sung_williams_sun_liu_lu_2022, title={Chemical Control of Magnetic Ordering in Hybrid Fe-CI Layered Double Perovskites}, volume={34}, ISSN={["1520-5002"]}, url={https://doi.org/10.1021/acs.chemmater.2c00163}, DOI={10.1021/acs.chemmater.2c00163}, abstractNote={Recent discoveries of novel physics in two-dimensional (2D) magnetic materials have sparked the search of new layered magnetic semiconductors. Compared to the traditional inorganic 2D van der Waals crystals, hybrid organic–inorganic metal–halide frameworks offer significantly enhanced chemical and structural versatility, where their optical, electronic, and magnetic properties can be readily modulated with both organic and inorganic components. Here, we reported a series of new Fe–Cl-based layered double perovskites LnMIMIIICl8, [n = 4, L = phenylethylammonium or chiral R-(+)-β-methylphenethylammonium and n = 2, L = 1,4-butanediammonium; MI = Ag/Na; MIII = Fe/In]. UV–vis measurements show that their optical band gaps are highly tunable by varying the organic cations, MI ion, and MIII ion. Magnetic susceptibility measurements suggest an antiferromagnetic coupling between the nearest FeIII–FeIII, where the Curie–Weiss temperature, Néel temperature, and frustration factors can be easily modulated with their compositions and dimensionality. Our study demonstrates the rich and interesting magnetic properties in these layered transition-metal–halide double perovskites and paves the way for design of multifunctional magnetic materials.}, number={6}, journal={CHEMISTRY OF MATERIALS}, publisher={American Chemical Society (ACS)}, author={Xue, Jie and Wang, Ziyu and Comstock, Andrew and Wang, Zhiyu and Sung, Herman H. Y. and Williams, Ian D. and Sun, Dali and Liu, Junwei and Lu, Haipeng}, year={2022}, month={Mar}, pages={2813–2823} }
 @article{comstock_biliroglu_seyitliyev_mcconnell_vetter_reddy_kirste_szymanski_sitar_collazo_et al._2022, title={Spintronic Terahertz Emission in Ultrawide Bandgap Semiconductor/Ferromagnet Heterostructures}, volume={10}, ISSN={["2195-1071"]}, DOI={10.1002/adom.202201535}, abstractNote={Abstract}, journal={ADVANCED OPTICAL MATERIALS}, author={Comstock, Andrew and Biliroglu, Melike and Seyitliyev, Dovletgeldi and McConnell, Aeron and Vetter, Eric and Reddy, Pramod and Kirste, Ronny and Szymanski, Dennis and Sitar, Zlatko and Collazo, Ramon and et al.}, year={2022}, month={Oct} }