EHPRG: The European High Pressure Research Group

Welcome

Welcome to the official website of the European High Pressure Research Group (EHPRG).

EHPRG is non-profitable academic association established in 1963 which is devoted to science and technology of matter under high pressure. It organizes an annual meeting which brings together hundreds of scientists of various fields, mainly physics, chemistry, Earth and planetary sciences, bio- and food science and technology.

The reasonable size of the group, low conference fees, and a friendly relationship between the attendants have made EHPRG meetings a major event in the European high-pressure community for more than half a century.

Upcoming EHPRG Meeting

The 58th European High Pressure Research Group Meeting on High Pressure Science and Technology (EHPRG-2020) will be held in Tenerife, Spain, from 6th to 11th September 2020. The 58th EHPRG Meeting will be chaired by Alfonso Muñoz Gonzalez (Universidad de La Laguna, Tenerife, Spain).
For more information, please visit the official webpage of the 58th EHPRG Meeting.

High-pressure in the headlines

Selection of high-pressure related titles from top scientific journals.

Will the pandemic permanently alter scientific publishing?

by Ewen Callaway

Nature, Published online: 03 June 2020; doi:10.1038/d41586-020-01520-4

3 Jun 2020 at 12:00am

Ice goes fully cubic

by Christoph G. Salzmann

Nature Materials, Published online: 27 May 2020; doi:10.1038/s41563-020-0696-6

27 May 2020 at 12:00am

Gas chromatography-mass spectrometry analyses of encapsulated stable perovskite solar cells

by Shi, L., Bucknall, M. P., Young, T. L., Zhang, M., Hu, L., Bing, J., Lee, D. S., Kim, J., Wu, T., Takamure, N., McKenzie, D. R., Huang, S., Green, M. A., Ho-Baillie, A. W. Y.

Although perovskite solar cells (PSC’s) have produced remarkable energy conversion efficiencies, their underperforming durability is the key challenge for the technology to be commercially viable. In this work, for the first time, we use gas chromatography – mass spectrometry (GC-MS) to reveal signature volatile products of the decomposition of organic hybrid perovskites under thermal stress. In addition, we are able to use GC-MS to confirm that a low-cost polymer/glass stack pressure-tight encapsulation is effective in supressing such outgassing. Using such encapsulation scheme, CH3NH3 (MA) containing multi-cation multi-halide perovskite solar cells survived more than 1800 hours of Damp Heat test and 75 cycles of Humidity Freeze test exceeding the requirement of IEC61215:2016 standard for the first time.

21 May 2020 at 7:48pm

In situ X-ray diffraction of silicate liquids and glasses under dynamic and static compression to megabar pressures [Earth, Atmospheric, and Planetary Sciences]

by Guillaume Morard, Jean-Alexis Hernandez, Marco Guarguaglini, Riccardo Bolis, Alessandra Benuzzi-Mounaix, Tommaso Vinci, Guillaume Fiquet, Marzena A. Baron, Sang Heon Shim, Byeongkwan Ko, Arianna E. Gleason, Wendy L. Mao, Roberto Alonso-Mori, Hae Ja Lee, Bob Nagler, Eric Galtier, Dimosthenis Sokaras, Siegfried H. Glenzer, Denis Andrault, Gaston Garbarino, Mohamed Mezouar, Anja K. Schuster, Alessandra Ravasio

2 Jun 2020 at 6:01pm

High-Pressure Polymeric Nitrogen Allotrope with the Black Phosphorus Structure

by Dominique Laniel, Bjoern Winkler, Timofey Fedotenko, Anna Pakhomova, Stella Chariton, Victor Milman, Vitali Prakapenka, Leonid Dubrovinsky, and Natalia Dubrovinskaia

Studies of polynitrogen phases are of great interest for fundamental science and for the design of novel high energy density materials. Laser heating of pure nitrogen at 140 GPa in a diamond anvil cell led to the synthesis of a polymeric nitrogen allotrope with the black phosphorus structure, bp-N. ...

28 May 2020 at 12:00pm

Plastic and Superionic Helium Ammonia Compounds under High Pressure and High Temperature

by Cong Liu, Hao Gao, Andreas Hermann, Yong Wang, Maosheng Miao, Chris J. Pickard, Richard J. Needs, Hui-Tian Wang, Dingyu Xing, and Jian Sun

Stable compounds made from helium and ammonia are predicted to form at the extreme pressures found inside Neptune and Uranus.

9 Apr 2020 at 12:00pm

Solids, liquids, and gases under high pressure

by Ho-Kwang Mao, Xiao-Jia Chen, Yang Ding, Bing Li, and Lin Wang

The effect of adding high pressure as a control parameter in solids, liquids, and gases expands opportunities to observe unexpected novel phenomena and understand matter in extreme environments. This review on high pressure science highlights subjects ranging from quantum criticality to Earth science. State-of-the-art experimental methods at megabar pressures are also discussed. The proliferation of pressure-induced phases illustrate promising new directions for this field of research.

20 Mar 2018 at 11:00am

Colloquium: High pressure and road to room temperature superconductivity

by Lev P. Gor’kov and Vladimir Z. Kresin

Even after three decades of development, high-temperature superconductivity remains one of the most challenging theoretical and experimental areas in condensed matter physics. In this Colloquium some new discoveries in this area are reviewed and possible routes toward much higher transition temperatures are analyzed.

9 Jan 2018 at 11:00am

Monoclinic semimetal IrSi synthesized under high pressure above 25 GPa: Crystal structure, electronic, and magnetic properties

by Y. Fujishiro, N. Kanazawa, T. Shinmei, M. Nishi, T. Nakajima, T. Arima, D. Hashizume, M. S. Bahramy, T. Irifune, and Y. Tokura

Transition metal monosilicides exhibit diverse physical properties depending on their crystal structures. Regarding IrSi, only the MnP-type orthorhombic form has been known so far. In this paper, the authors report a successful synthesis of a monoclinic phase through high-pressure high-temperature treatment above 25 GPa, while the theoretically predicted B20-type cubic structure has not been identified up to 48 GPa. Magneto-transport measurements reveal a semimetallic nature of the monoclinic form with a low carrier density of ~1019 /cm3. Combined with large Rashba spin splitting of surface electronic bands, monoclinic IrSi may offer a potential material platform for versatile spintronic applications in the two-dimensional limit.

15 May 2020 at 12:00pm

Pressure tuning of the anomalous Hall effect in the chiral antiferromagnet ${\mathrm{Mn}}_{3}\mathrm{Ge}$

by R. D. dos Reis, M. Ghorbani Zavareh, M. O. Ajeesh, L. O. Kutelak, A. S. Sukhanov, Sanjay Singh, J. Noky, Y. Sun, J. E. Fischer, K. Manna, C. Felser, and M. Nicklas

We report on the pressure evolution of the giant anomalous Hall effect (AHE) in the chiral antiferromagnet ${\mathrm{Mn}}_{3}\mathrm{Ge}$. The AHE originating from the nonvanishing Berry curvature in ${\mathrm{Mn}}_{3}\mathrm{Ge}$ can be continuously tuned by application of hydrostatic pressure. At ...

7 May 2020 at 12:00pm

First-order amorphous-to-amorphous phase transitions during lithiation of silicon thin films

by Jinghui Miao, Baoming Wang, and Carl V. Thompson

First-order amorphous-to-amorphous phase transitions (polyamorphic transitions) are rarely observed and have been associated with pressure or temperature changes. The authors report first-order polyamorphic transitions caused by changes in composition. Observations were made during electrochemical insertion of lithium into amorphous silicon films under potentiostatic conditions. Kinetic analyses using the Johnson-Mehl-Avrami-Kolmogorov model applied to measurements of current as a function of time at different overpotentials indicate nucleation and growth of Li-rich phases throughout the volume of the films. This conclusion is supported by electron microscope images of twophase amorphous films with image contrast provided through preferential high energy electron sputtering of Li from Li-rich phases.

30 Apr 2020 at 12:00pm

Pressure effect on the anomalous Hall effect of ferromagnetic Weyl semimetal $\mathrm{C}{\mathrm{o}}_{3}\mathrm{S}{\mathrm{n}}_{2}{\mathrm{S}}_{2}$

by Z. Y. Liu, T. Zhang, S. X. Xu, P. T. Yang, Q. Wang, H. C. Lei, Y. Sui, Y. Uwatoko, B. S. Wang, H. M. Weng, J. P. Sun, and J.-G. Cheng

The magnetic Weyl semimetal $\mathrm{C}{\mathrm{o}}_{3}\mathrm{S}{\mathrm{n}}_{2}{\mathrm{S}}_{2}$ exhibits large anomalous Hall effect (AHE) due to its nontrivial band topology with enhanced Berry curvature. Here we investigate the pressure effect on the AHE of $\mathrm{C}{\mathrm{o}}_{3}\mathrm{S}...

28 Apr 2020 at 12:00pm

High pressure investigation of an organic three-dimensional Dirac semimetal candidate having a diamond lattice

by Andhika Kiswandhi, Mitsuhiko Maesato, Shinya Tomeno, Yukihiro Yoshida, Yasuhiro Shimizu, Prashant Shahi, Jun Gouchi, Yoshiya Uwatoko, Gunzi Saito, and Hiroshi Kitagawa

$(\mathrm{ET}){\mathrm{Ag}}_{4}{(\mathrm{CN})}_{5}$ [ET = BEDT-TTF: bis(ethylenedithio)tetrathiafulvalene] is a rare example of organic conductors that crystallizes in a diamond structure due to the tetrahedral arrangement of neighboring ET molecules. Because each ET has a $+1$ site charge, the band...

5 Jun 2020 at 12:00pm

Ge coordination in $\mathrm{NaAlG}{\mathrm{e}}_{3}{\mathrm{O}}_{8}$ glass upon compression to 131 GPa

by Marija Krstulović, Angelika D. Rosa, Nicole Biedermann, Georg Spiekermann, Tetsuo Irifune, Manuel Muñoz, and Max Wilke

Structural transformations at high pressure in $\mathrm{NaAlG}{\mathrm{e}}_{3}{\mathrm{O}}_{8}$ glass were investigated by means of x-ray absorption spectroscopy at the Ge $K$ edge in combination with a diamond anvil cell. The obtained results provide a detailed picture of the local structural behav...

4 Jun 2020 at 12:00pm

Approaching the quantum critical point in a highly correlated all-in–all-out antiferromagnet

by Yishu Wang, T. F. Rosenbaum, D. Prabhakaran, A. T. Boothroyd, and Yejun Feng

All-in–all-out (AIAO) antiferromagnets demonstrate vividly the effects of correlated charge and spin with strong spin-orbit coupling. Here, using resonant magnetic x-ray diffraction, the authors directly track the evolution of AIAO order in the pyrochlore Sm2Ir2O7 across a pressure-tuned quantum critical point. The results demonstrate a powerful approach to the quantum critical state driven by electron correlations U/t and spin orbit coupling λ/t. The authors find prominent Ising-type spin fluctuations under pressure instead of the Heisenberg-type seen via chemical doping. This work also circumscribes the region of interest for the putative magnetic Weyl semimetal state in Pressure-Temperature space.

4 Jun 2020 at 12:00pm

Structural distortions in rare-earth transition-metal oxide perovskites under high pressure

by J.-S. Zhou

Owing to their structural complexity and wide range of possible chemical combinations, perovskite oxides exhibit many technically important physical properties. Pressure is a thermodynamic parameter which is useful for tuning physical properties; however, the response of the complex crystal structur...

4 Jun 2020 at 12:00pm

${\mathrm{BaZrO}}_{3}$ stability under pressure: The role of nonlocal exchange and correlation

by Erik Jedvik Granhed, Göran Wahnström, and Per Hyldgaard

The ground-state structure of ${\mathrm{BaZrO}}_{3}$ is experimentally known to be cubic down to absolute zero. However, there exist several measured properties and experimental characterizations that earlier computational works have failed to accurately describe and explain within this cubic symmet...

4 Jun 2020 at 12:00pm

Superconductivity in Ce-based heavy-fermion systems under high pressure

by Van-Nham Phan

In this paper, the possibility of a superconducting state mediated by the valence fluctuations in Ce-based heavy-fermion systems under high pressure is investigated for the extended periodic Anderson model. In this extended version, an additional local Coulomb repulsion between the localized and con...

4 Jun 2020 at 12:00pm

High-pressure structural and electronic properties of $\mathrm{Cu}M{\mathrm{O}}_{2}$ $(M=\mathrm{Cr}, \mathrm{Mn})$ delafossite-type oxides

by D. Levy, E. Greenberg, S. Layek, M. P. Pasternak, I. Kantor, S. Pascarelli, C. Marini, Z. Konopkova, and G. Kh. Rozenberg

We report high-pressure x-ray diffraction, x-ray absorption spectroscopy, and electrical transport measurements on $\mathrm{Cu}M{\mathrm{O}}_{2}$ ($M=\mathrm{Cr}$, Mn) delafossitelike oxides in an attempt to study their structural and electronic evolution with pressure. Recent studies of the similar...

4 Jun 2020 at 12:00pm

Pressure-induced suppression of ferromagnetism in the itinerant ferromagnet ${\mathrm{LaCrSb}}_{3}$

by Z. E. Brubaker, J. S. Harvey, J. R. Badger, R. R. Ullah, D. J. Campbell, Y. Xiao, P. Chow, C. Kenney-Benson, J. S. Smith, C. Reynolds, J. Paglione, R. J. Zieve, J. R. Jeffries, and V. Taufour

The experimental characterization of materials under high pressure is often limited to a few properties. Usually, this is insufficient for a detailed understanding of the underlying physics. Here, the authors report a suite of high-pressure experiments probing the ferromagnetic state in LaCrSb3. They assess the Curie temperature, crystal structure, and evolution of the magnetic moment as obtained from the integrated absolute difference in x-ray emission spectroscopy. The Curie temperature appears to be driven by the Cr moment, which decreases smoothly in contrast to the pair of steplike decrease features predicted by density functional theory.

3 Jun 2020 at 12:00pm

Room-temperature polar metal stabilized under high pressure

by J.-J. Gao, S.-Y. Fu, K. Yamaura, J. F. Lin, and J.-S. Zhou

$\mathrm{LiOs}{\mathrm{O}}_{3}$ synthesized under high pressure in recent years is a rare metal since it undergoes a nonpolar to polar phase transition at ${T}_{s}=140\phantom{\rule{0.16em}{0ex}}\mathrm{K}$. Forming a polar axis through a phase transition in a metal seems against common sense. It is...

2 Jun 2020 at 12:00pm

Metal-insulator and magnetic phase diagram of ${\mathrm{Ca}}_{2}{\mathrm{RuO}}_{4}$ from auxiliary field quantum Monte Carlo and dynamical mean field theory

by Hongxia Hao, Antoine Georges, Andrew J. Millis, Brenda Rubenstein, Qiang Han, and Hao Shi

Layered perovskite ruthenium oxides exhibit a striking series of metal-insulator and magnetic-nonmagnetic phase transitions easily tuned by temperature, pressure, epitaxy, and nonlinear drive. In this work, we combine results from two complementary state-of-the-art many-body methods, auxiliary field...

2 Jun 2020 at 12:00pm

Magnetotransport properties of tellurium under extreme conditions

by Kazuto Akiba, Kaya Kobayashi, Tatsuo C. Kobayashi, Ryo Koezuka, Atsushi Miyake, Jun Gouchi, Yoshiya Uwatoko, and Masashi Tokunaga

This study investigates the transport properties of a chiral elemental semiconductor tellurium (Te) under magnetic fields and pressure. Application of hydrostatic pressure reduces the resistivity of Te, while its temperature dependence remains semiconducting up to 4 GPa, contrary to recent theoretic...

2 Jun 2020 at 12:00pm

High-pressure synthesis of heavily hole-doped cuprates ${\mathrm{Mg}}_{1−x}{\mathrm{Li}}_{x}{\mathrm{Cu}}_{2}{\mathrm{O}}_{3}$ with quasi-one-dimensional structure

by Yoshinori Imai, Koya Sasaki, Takuya Aoyama, Kenji Shirasaki, Tomoo Yamamura, and Kenya Ohgushi

We investigate electronic properties of hole-doped cuprates ${\mathrm{Mg}}_{1−x}{\mathrm{Li}}_{x}{\mathrm{Cu}}_{2}{\mathrm{O}}_{3}$ with the quasi-one-dimensional two-leg-ladder structure. We succeeded in extending the solubility limit of Li in ${\mathrm{Mg}}_{1−x}{\mathrm{Li}}_{x}{\mathrm{Cu}}_{2}{...

2 Jun 2020 at 12:00pm

Pressure effect on the electromotive force of the type R thermocouple

by Yu Nishihara

23 Dec 2019 at 12:29pm

Phase relations in the Fe-P system at high pressures and temperatures from ab initio computations

by Nursultan E. Sagatov

17 Mar 2020 at 5:28am

TiB2-reinforced B4C composites produced by reaction sintering at high-pressure and high temperature

by Xiaonan Wang

9 Apr 2020 at 8:54am

TiC-MgO composite: an X-ray transparent and machinable heating element in a multi-anvil high pressure apparatus

by Fang Xu