Related papers: Bulk Aluminum at High Pressure: A First-Principles…
Studies of the behaviour of solids at ultra-high pressures, those beyond 200 GPa, contribute to our fundamental understanding of materials properties and allow an insight into the processes happening at such extreme conditions relevant for…
Within the micro-canonical ensemble phase transitions of first order can be identified without invoking the thermodynamic limit. We show for the liquid-gas transition of sodium, potassium, and iron at normal pressure that the transition…
The thermodynamic properties of the superconducting state induced in metallic molecular hydrogen under the influence of pressure 347 GPa were determined. In particular, it has been shown that the critical temperature ($T_{C}$) changes in…
The Mg-Zn and Al-Zn binary alloys have been investigated theoretically under static isotropic pressure. The stable phases of these binaries on both initially hexagonal-close-packed (HCP) and face-centered-cubic (FCC) lattices have been…
In this lecture we review high-pressure phase transition sequences exhibited by simple elements, looking at the examples of the main group I, II, IV, V, and VI elements. General trends are established by analyzing the changes in…
Metallic hydrogen is expected to exhibit remarkable physics. Examples include high-temperature superconductivity and possible novel types of quantum fluids. These could have revolutionary practical applications. The pressures required to…
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…
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,…
The compressibility of solid helium (3He and 4He) in the hcp and fcc phases has been studied by path-integral Monte Carlo. Simulations were carried out in both canonical (NVT) and isothermal-isobaric (NPT) ensembles at temperatures between…
We investigate the high-pressure phase of the iron-based superconductor FeSe$_{0.89}$S$_{0.11}$ using transport and tunnel diode oscillator studies. We construct detailed pressure-temperature phase diagrams that indicate that outside of the…
Elemental materials provide clean and fundamental platforms for studying superconductivity. However, the highest superconducting critical temperature (Tc) yet observed in elements has not exceeded 30 K. Discovering elemental superconductors…
Whereas dhcp La superconducts at ambient pressure with Tc = 5 K, the other trivalent d-electron metals Sc, Y, and Lu only superconduct if high pressures are applied. Earlier measurements of the pressure dependence of Tc for Sc and Lu metal…
We report a joint experimental and theoretical study of the structural, vibrational, and electronic properties of layered monoclinic arsenic sulfide (alpha-As2S3), aka mineral orpiment, under compression. X-ray diffraction and Raman…
We present temperature dependent resistivity and ac-calorimetry measurements of CeVSb3 under pressure up to 8 GPa in a Bridgman anvil cell modified to use a liquid medium and in a diamond anvil cell using argon as a pressure medium,…
Conclusive crystal structure determination of the high pressure phases of hydrogen remains elusive due to lack of core electrons and vanishing wave vectors, rendering standard high-pressure experimental methods moot. Ab-initio DFT…
Accurate spectroscopic investigations of the heaviest elements are inherently challenging, due to their short lifetimes and low production yields. Success of such measurements requires both dedicated experimental techniques and strong…
In Pr$_{0.7}$Ca$_{0.3}$MnO$_{3}$, pressure induces reentrant magnetic and electronic state changes in the range 1 atm to $\sim$ 6 GPa. The metal-insulator and magnetic transition temperatures coincide from $\sim$1 to 5 GPa, decouple outside…
This study focuses on the investigations and comparative study of the electronic structure of Co$_2$VZ (Z=Al, Be) Heusler alloys under varying high pressure conditions. The pressure range explored spans from 0.0 GPa to 30.0GPa, with…
Superconducting properties of bulk, dense, pure MgB2 and doped (Mg1-xAx)B2 samples with A = Na, Ca, Cu, Ag, Zn and Al were studied for compositional ranges 0 < x < 0.20. The effect on pinning properties and critical current were…
We study the acoustic emission avalanches during the failure process of porous alumina samples (Al2O3) under compression. Specimens with different porosities ranging from 30% to 59% have been synthetized from a mixture of fine-grained…