JUNE 18, 2018 — A new study from a team of scientists, which comprised of HPSTAR’s Philip Dalladay-Simpson and Ross T. Howie, proposed a promising candidate crystal structure for their recently discovered phase of hydrogen, phase V. Most poignantly the work, which was recently published Physical Review Letters, provides further evidence that phase V is indeed a stepping stone towards hydrogen’s ...
AUGUST 17, 2018 — New work from a team of scientists including Dr. Yang Ding from HPSTAR confirm that Kitaev-quantum-spin candidate material, a-Li2IrO3 will lose its exotic quantum state under compression instead of becoming predicted Kitaev spin liquid from multiple in-situ characterizations combined with theoretical calculations. This work is published in recent NPJ Quantum Materials.
JULY 26, 2018 — The phenomenon of metastability, in which a system is in a state that is stable but not at the lowest energy, is obtained most-commonly through fast cooling from high temperature. Now, a team of scientists co-led by Dr. Gang Liu from HPSTAR report attainable metastable states in 2D solar perovskites from compression-decompression paths. The metastable phases show much superior...
JULY 19, 2018 — New report from a team of scientists led by Dr. Duck Young Kim from HPSTAR, found that their recently synthesized silicon allotrope, namely Si24, with nanoscale porous structure showed extremely favorable thermoelectric properties with slightly doping, comparing with normal silicon. This work is published in recent Nano Letters.
JULY 14, 2018 — New work from a group of scientists led by Dr. Yang Ding of HPSTAR, provided the first experimental evidence of lattice inhomogeneity in high-temperature superconductors and found that the structural inhomogeneity correlates well with superconductivity in single-crystal Bi-2212—bismuth-based cuprate (Bi2Sr2CaCu2O8+δ) at high pressure. This study is published in the Journal of...
JUNE 6, 2018 — High pressure can profoundly affect electronic structure and reactivity, creating compounds between elements that do not react at ambient conditions. Lithium is known to react with gold and silver, however no copper compounds are known to date. New study by a group of HPSTAR scientists reports that by compressing mixtures of the elements in diamond-anvil cells, compounds of lithium ...
MARCH 31, 2018 — Through high-pressure experiment studies on bridgmanite, the most abundant mineral in the Earth’s mantle, a group of scientists include Dr. Yonggang Wang of HPSTAR, determined the influence of spin state and valence state of Fe on bridgmanite density, bulk sound velocity, and electrical conductivity. Based on their high-pressure experimental data on Fe3+-only bridgmanite together ...
MAY 16, 2018 — After continuous insistence on the pressure-driven spin-crossover in transition metal chalcogenides, a group of scientists co-led by Dr. Wenge Yang and Dr. Yonggang Wang of HPSTAR, firstly observed the emergence of superconductivity in Fe-based honeycomb lattice under compression. Before this, all the iron-based high-Tc superconductors structurally adopt FeSe-type square Fe lattice....
APRIL 28, 2018 — Pressure-induced phase transition always involves symmetry and coordination change in a crystal. While researchers most focus on symmetry change instead of considering its coordination or local bonding varying when a crystal structure changed. A team of scientists led by Dr. Haozhe Liu of HPSTAR find a general coordination increase in VO2 phase transitions and state that this...
JANUARY 31, 2018 — Superconductivity is a physical state occurring in certain materials, called superconductors, in which electrical resistance disappears completely when cooled below a characteristic critical temperature. This phenomenon can be induced under chemical and high external pressure conditions. New work from a team including Dr. Jinglong Zhu of HPSTAR found superconducting MoS2 under...
APRIL19, 2018 — The compound BaPd2As2 represents the end member of the Pd-doped series and exists in the form of two types of crystal structures: ThCr2Si2-structure type (I4/mmm) and CeMg2Si2-structure type (P4/mmm). The former structure has bulk superconductivity, while in the latter structure only filamentary superconductivity was observed below 2 K. This shows that the crystal structure has a...
APRIL 18, 2018 — The synthesis and properties of hydrogen-bearing compounds is an intensively studied area of physics and chemistry, mainly driven by hydrogen-storage applications. High pressure and high temperature have been an effective route to synthesis hydrides with extremely high hydrogen content. A new study by RTH lab, reports the discovery of new cobalt compounds, CoH and CoH2, with high...
MARCH 20, 2018 — Pressure has long been recognized as a fundamental thermodynamic variable. It drastically alters physical and chemical properties of materials. A review on Reviews of Modern Physics from HPSTAR researchers led by Dr. Ho-Kwang, provides an in-depth review of how pressure drastically change our world and the key developments that have led to surprising high-pressure physics and...
MARCH 7, 2018 — The Earth’s lower mantle comprises >55% by volume of our planet, extending from 670 to 2900 kilometers in depth. The lower mantle is potentially the most massive water reservoir in our planet, which largely depends on availability of hydrous minerals which can store and transport water down to the deep lower mantle. Through high-pressure-temperature experiments in a laser-heated...
FEBRUARY 11, 2018 — Diamond anvil cell (DAC) has been used for almost 60 years to simulate extreme pressure environments, it holds the static pressure record generated in laboratories on the earth. Although some studies have demonstrated techniques to generate 4 million atmosphere pressures (400 GPa) – the generally accepted limit pressure of a conventional DAC, yet few have examined how the DAC...
FEBRUARY 5, 2018 — Hydrogen-rich compounds have attracted attention because of their potential application in hydrogen storage and for high-Tc superconductivity. High-pressure methods have proven very effective in the search for new materials with high hydrogen contents. A new study led by Dr Jack Binns, a postdoctoral researcher in the group of Dr Ross Howie, reports the discovery of a new high-...
NOVEMBER 23, 2017 — Free oxygen in the air that gives life to our living planet cannot be taken for granted. In fact, during the first half of the Earth’s 4.6 billion year history, oxygen was absent in the atmosphere. Only 2.4 billion years ago at the Great Oxidation Event (GOE), oxygen appeared suddenly, thus enabling the aerobic life like us to thrive and evolve. In seeking for possible source...
NOVEMBER 20, 2017 — The observation of high-temperature superconductivity in hydride sulfide (H2S) at high pressures has generated considerable interest in compressed hydrogen-rich compounds. The heavier hydrogen chalcogenides (i.e., H2Se and H2Te) are predicted to also exhibit high Tc superconductivity, however up until now remained experimentally unexplored. A new study led by Dr. Ross Howie of ...
NOVEMBER 3, 2017 — It is proposed that the lattice water does not act as an electron donor but serves to change the electro transfer energetic through its unique polarity and hydrogen bonding capability. New study led by Dr. Lin Wang of HPSTAR and Prof. Enqi Gao of East China Normal University found that the higher the water content in the lattice, the less sensitively the compounds respond to...
OCTOBER 30, 2017 — A group of scientists co-led by Dr. Shengcai Zhu of HPSTAR, investigated the evolution of hyper structure and screw dislocation for the framework material zeolite MTW, a useful industrial solid acid catalyst. They revealed that the complex screw dislocation core in zeolite MTW was composed by different crystal domains with different stacking vector. Their findings are published ...