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Unveiling a novel metal-to-metal transition in LuH_(2):Critically challenging superconductivity claims in lutetium hydrides

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Matter and Radiation at Extremes 2024年第3期9卷 65-73页

作者： Dong Wang Ningning Wang Caoshun Zhang Chunsheng Xia Weicheng Guo Xia Yin Kejun Bu Takeshi Nakagawa Jianbo Zhang Federico Gorelli Philip Dalladay-Simpson Thomas Meier Xujie Lü Liling Sun Jinguang Cheng Qiaoshi Zeng Yang Ding ho-kwang mao Center for High-Pressure Science and Technology Advanced Research Beijing 100094China Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China Shanghai Key Laboratory of Material Frontiers Research in Extreme Environments(MFree) Shanghai Advanced Research in Physical Sciences(SHARPS)Shanghai 201203China

Following the recent report by Dasenbrock-Gammon et al.[Nature 615,244–250(2023)]of near-ambient superconductivity in nitrogendoped lutetium trihydride(LuH_(3-δ)N_(ε)),significant debate has emerged surrounding the composition and interpretation of the observed sharp resistance ***,we meticulously revisit these claims through comprehensive characterization and *** definitively identify the reported material as lutetium dihydride(LuH_(2)),resolving the ambiguity surrounding its *** similar conditions(270–295 K and 1–2 GPa),we replicate the reported sharp decrease in electrical resistance with a 30%success rate,aligning with the observations by Dasenbrock-Gammon et ***,our extensive investigations reveal this phenomenon to be a novel pressure-induced metal-to-metal transition intrinsic to LuH_(2),distinct from ***,nitrogen doping exerts minimal impact on this *** work not only elucidates the fundamental properties of LuH_(2)andLuH_(3),but also critically challenges the notion of superconductivity in these lutetium hydride *** findings pave the way for future research on lutetium hydride systems,while emphasizing the crucial importance of rigorous verification in claims of ambient-temperature superconductivity.

关键词： resistance hydride superconductivity

Harnessing chemical pressure

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National Science Review 2023年第12期10卷 45-47页

作者： ho-kwang mao Shanghai Advanced Research in Physical Sciences(SHARPS)

Pressure profoundly changes all physical characteristics of a condensed matter and provides a vast and fertile dimension to search for materials with extremely favorable properties for technological applications [1,2]. however, these favorable properties are only optimally tuned at a specific high pressure and will vanish or revert at the ambient pressure, rendering them merely of academic interest.

关键词： SUPERCONDUCTIVITY CU HYDRIDE

Dense hydrous silica carrying water to the deep Earth and promotion of oxygen fugacity heterogeneity

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Matter and Radiation at Extremes 2022年第6期7卷 76-78页

作者： Yanhao Lin ho-kwang mao Center for High Pressure Science and Technology Advanced Research Beijing 100193People’s Republic of China

Water has remarkable effects on the properties of mantle rocks,but,owing to the high temperatures in the mantle,uncertainties remain about how and how much water is transported into the deep *** studies have shown that stishovite and post-stishovites as highpressure phases of SiO2 have the potential to carry weight percent levels of water into the Earth’s interior along the geotherm of the subducting oceanic *** slabs are subducted to the deepest mantle,dehydration of these dense hydrous silica phases has the potential to change the physicochemical properties of the mantle by reducing melting points,forming new high-pressure phases,and enhancing the oxygen fugacity heterogeneity of the lower mantle.

关键词： Earth mantle silica

Born’s valence force-field model for diamond at terapascals: Validity and implications for the primary pressure scale

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Matter and Radiation at Extremes 2021年第6期6卷 104-110页

作者： Qingyang Hu ho-kwang mao Center for High Pressure Science and Technology Advanced Research Beijing 100094China

Born’s valence force-field model(VFM)established a theoretical scheme for calculating the elasticity,zero-point optical mode,and lattice dynamics of diamond and diamond-structured *** particular,the model enabled the derivation of a numerical relation between the elastic moduli and the Raman-active F2g mode for ***,we establish a relation between the diamond Raman frequencyωand the bulk modulus K through first-principles calculation,rather than *** calculated K exhibits a combined uncertainty of less than 5.4%compared with the results obtained from the analytical equation of the *** results not only validate Born’s classic model but also provide a robust K–ωfunctional relation extending to megabar pressures,which we use to construct a primary pressure scale through Raman spectroscopy and the crystal structure of *** computations also suggest that currently used pressure gauges may seriously overestimate pressures in the multi-megabar regime.A revised primary scale is urgently needed for such ultrahigh pressure experiments,with possible implications for hot superconductors,ultra-dense hydrogen,and the structure of the Earth’s core.

关键词： valence gauge elasticity

Geomimicry—Liberating high-pressure research by encapsulation

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Matter and Radiation at Extremes 2022年第6期7卷 79-81页

High pressures induce changes of properties and structures that could greatly impact materials science if such changes were preserved for ambient *** the geological process of diamond formation that the pressures and high-pressure phases in diamond inclusions can be preserved by the strong diamond envelope,we discuss the perspectives that such process revolutionizes high-pressure science and technology and opens a great potential for creation of functional materials with extremely favorable properties.

关键词： properties ambient process

Role of hydrogen and proton transportation in Earth’s deep mantle

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Matter and Radiation at Extremes 2021年第6期6卷 56-57页

作者： Qingyang Hu ho-kwang mao Center for High Pressure Science and Technology Advanced Research Beijing 100094China

Hydrogen(H)is the most abundant element in the known universe,and on the Earth’s surface it bonds with oxygen to form water,which is a distinguishing feature of this *** the Earth’s deep mantle,His stored hydroxyl(OH−)in hydrous or nominally anhydrous *** its ubiquity on the surface,the abundance ofHin the Earth’s deep interior is *** of the totalHbudget in the Earth’s interior have ranged from less than one hydrosphere,which assumes an H-depleted interior,to hundreds of hydrospheres,which assumes thatHis siderophile(iron-loving)in the *** discrepancy raises the questions of how H is stored and transported in the Earth’s deep interior,the answers to which will constrain its behavior in the deep lower mantle,which is defined as the layer between 1700 km depth and the core–mantle boundary.

关键词： interior hundreds planet

Key problems of the four-dimensional Earth system

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Matter and Radiation at Extremes 2020年第3期5卷 31-39页

作者： ho-kwang mao Wendy L.mao Center for High Pressure Science and Technology Advanced Research 10 Dongbeiwang West RoadHaidianBeijing 100094China Department of Geological Sciences Stanford UniversityStanfordCalifornia 94305USA Stanford Institute for Materials and Energy Sciences SLAC National Accelerator LaboratoryMenlo ParkCalifornia 94025USA

Compelling evidence indicates that the solid Earth consists of two physicochemically distinct zones separated radially in the middle of the lower mantle at∼1800 km *** inner zone is governed by pressure-induced physics and chemistry dramatically different from the conventional behavior in the outer *** differences generate large physical and chemical potentials between the two zones that provide fundamental driving forces for triggering major events in Earth’s *** of the main chemical carriers between the two zones isH_(2)Oin hydrous minerals that subducts into the inner zone,releases hydrogen,and leaves oxygen to create superoxides and form oxygen-rich piles at the core–mantle boundary,resulting in localized net oxygen gain in the inner *** of oxygen-rich piles at the base of the mantle could eventually reach a supercritical level that triggers eruptions,injecting materials that cause chemical mantle convection,superplumes,large igneous provinces,extreme climate changes,atmospheric oxygen fluctuations,and mass *** research will be the key for advancing a unified theory of the four-dimensional Earth system.

关键词： zone. Earth mantle

Yi-Gang Xu: the Earth's deep interior holds the key to habitability

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National Science Review 2021年第4期8卷 35-38页

作者： Jin Liu ho-kwang mao the Center for High Pressure Science and Technology Advanced Research (HPSTAR) HPSTAR

The deep Earth is the engine of whole Earth systems and plays a key role in surface evolution and geological hazards. Scientists have been deciphering the internal processes that shape our habitable planet, especially since the formulation of plate tectonics theory. To date, how the deep Earth works remains mysterious. At the end of 2020,

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Matter and Radiation at Extremes 2022年第6期7卷 1-2页

作者： ho-kwang maoa Center for High Pressure Science and Technology Advanced Research 10 Xibeiwang East RoadHaidianBeijing 100094China

The behavior of hydrogen under extreme pressure has continued to attract great interest among the physics,chemistry,materials science,and geoscience communities and has become a major driving incentive for cross-disciplinary advances in novel high-pressure *** has been particularly noticeable this year,and is one of the main themes of this“Special Issue on High Pressure Science 2021.”Hydrogen exhibits a rich physics of multiple phase transitions,including a predicted novel quantum state combining superconductivity and superfluidity upon metallization,and also provides benchmark values for testing theoretical models of quantum solids at high densities.

关键词： dimension driving solids