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Related papers: Metallic Hydrogen: Experiments on Metastability

200 papers

In recent years, metal hydride research has become one of the driving forces of the high-pressure community, as it is believed to hold the key to superconductivity close to ambient temperature. While numerous novel metal hydride compounds…

We develop a one-dimensional mathematical model for the loading process of hydrogen in a metal hydride tank. The model describes the evolution of the density and pressure of the hydrogen gas, the temperature of the tank, the averaged…

Materials Science · Physics 2025-07-31 Francesc Font , Attila Husar , Tim Myers , Maria Aguareles , Esther Barrabés

Hydrogen at high temperature and pressure undergoes a phase transition from a liquid molecular phase to a conductive atomic state, or liquid metallic hydrogen, sometimes referred to as the plasma phase transition (PPT). The PPT phase line…

Materials Science · Physics 2019-10-30 Matthew Houtput , Jacques Tempere , Isaac F. Silvera

Optical properties of compressed fluid hydrogen in the region where dissociation and metallization is observed are computed by ab-initio methods and compared to recent experimental results. We confirm that above 3000 K both processes are…

Materials Science · Physics 2019-09-04 Giovanni Rillo , Miguel A. Morales , David M. Ceperley , Carlo Pierleoni

Dias and Silvera (Letters, p. 715, 2017) claim the observation of the Wigner-Huntington transition to metallic hydrogen at 495 GPa. We show that neither the claims of the record pressure or the phase transition to a metallic state are…

Materials Science · Physics 2018-04-05 Xiao-Di Liu , Philip Dalladay-Simpson , Ross T. Howie , Bing Li , Eugene Gregoryanz

A vast amount of Raman spectroscopic data, obtained using diamond anvil cell technique under in situ high pressure-temperature conditions, has been used for mapping the phase transitions of hydrogen in the temperature range of 300 K to 900…

Materials Science · Physics 2022-01-19 Chang-Sheng Zha , Hanyu Liu , Zhongwu Wang , William A. Bassett

Two new phases of hydrogen have been discovered at room temperature in Ref.1: phase IV above 220 GPa and phase V above ~270 GPa. In the present work we have found a new phase VI at P~360 GPa and T<200 K. This phase is likely metallic as…

Materials Science · Physics 2016-01-19 M. I. Eremets , I. A. Troyan , A. P. Drozdov

Dissipationless quantum states, such as superconductivity and superfluidity, have attracted interest for almost a century. A variety of systems exhibit these macroscopic quantum phenomena, ranging from superconducting electrons in metals to…

Superconductivity · Physics 2007-05-23 Egor Babaev , Asle Sudbo , N. W. Ashcroft

The insulator-to-metal transition in dense fluid hydrogen is an essential phenomenon to understand gas giant planetary interiors and the physical and chemical behavior of highly compressed condensed matter. Using fast laser spectroscopy…

A possibility of high, room-temperature superconductivity was predicted for metallic hydrogen in the 1960s. However, metallization and superconductivity of hydrogen are yet to be unambiguously demonstrated in the laboratory and may require…

Hydrogen in metals is a significant research area with far-reaching implications, encompassing diverse fields such as hydrogen storage, metal-insulator transitions, and the recently emerging phenomenon of room-temperature ($\textit{$T_C$}$)…

Superconductivity · Physics 2023-11-30 Heejung Kim , Ina Park , J. H. Shim , D. Y. Kim

Dynamic compression has been used to synthesize liquid metallic hydrogen at 140 GPa (1.4 million bar) and experimental data and theory predict Al2O3 might be a metallic glass at ~300 GPa. The mechanism of metallization in both cases is…

Disordered Systems and Neural Networks · Physics 2015-05-20 W. J. Nellis

Manganese, in the a-Mn structure, has been studied using synchrotron powder x-ray diffraction in a diamond anvil cell up to 220 GPa at room temperature combined with density functional calculations (DFT). The experiment reveals an extended…

A novel diamond anvil cell suitable for electrical transport measurements under high pressure has been developed. A boron-doped metallic diamond film was deposited as an electrode onto a nano-polycrystalline diamond anvil using a microwave…

Superconductivity · Physics 2018-04-17 R. Matsumoto , Y. Sasama , M. Fujioka , T. Irifune , M. Tanaka , T. Yamaguchi , H. Takeya , Y. Takano

As the simplest element in nature, unraveling the phase diagram of hydrogen is a primary task for condensed matter physics. As conjectured many decades ago, in the low-temperature and high-pressure part of the phase diagram, solid hydrogen…

Superconductivity · Physics 2023-11-14 Mehmet Dogan , Sehoon Oh , Marvin L. Cohen

We present computer simulations of liquid and solid phases of condensed methane at pressures below 25 GPa, between 150 and 300 K, where no appreciable molecular dissociation occurs. We used molecular dynamics (MD) and metadynamics…

Materials Science · Physics 2015-05-13 Leonardo Spanu , Davide Donadio , Detlef Hohl , Giulia Galli

Recent experimental developments in hydrogen-rich materials in high pressures have put this class of materials above others in the race toward room temperature superconductivity. As it is the basis of all the materials in this class, the…

Superconductivity · Physics 2022-02-03 Mehmet Dogan , Sehoon Oh , Marvin L. Cohen

Production of metallic hydrogen is one of the top three open quests of physics. Recent low-temperature experiments report different metallization pressures, varying from 360GPa to 490GPa. In this work, we simulate structural properties,…

Materials Science · Physics 2020-01-29 Lorenzo Monacelli , Ion Errea , Matteo Calandra , Francesco Mauri

Hydrogen is the most abundant element in the universe, and its properties under conditions of high temperature and pressure are crucial to understand the interior of of large gaseous planets and other astrophysical bodies. At ultra high…

Materials Science · Physics 2013-03-12 Hanyu Liu , E. R. Hernandez , Jun Yan , Yanming Ma

Diatomic nitrogen is an archetypal molecular system known for its exceptional stability and complex behavior at high pressures and temperatures, including rich solid polymorphism, formation of energetic states, and an insulator-to-metal…