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Related papers: Novel magnesium borides and their superconductivit…

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We prepared MgB$_{2-x}$Be$_{x}$ ($x=0$, 0.2, 0.3, 0.4, and 0.6) samples where B is substituted with Be. MgB$_{2}$ structure is maintained up to $x=0.6$. In-plane and inter-plane lattice constants were found to decrease and increase,…

Superconductivity · Physics 2009-11-07 J. S. Ahn , Y. -J. Kim , M. -S. Kim , S. -I. Lee , E. J. Choi

The small atomic mass of boron indicates strong electron-phonon coupling, so it may have a brilliant performance in superconductivity. Recently, a new 2D boride sheet with ordered metal vacancies and surface terminals (Mo4/3B2-x) was…

Superconductivity · Physics 2023-11-14 Xiaoran Shi , Junfeng Gao , Shi Qiu , Yuan Chang , Luneng Zhao , Zhen-Guo Fu , Jijun Zhao , Ping Zhang

In this work we explore the phase diagram of the binary Nb-S system from ambient pressures up to 250 GPa using $ab$ $initio$ evolutionary crystal structure prediction. We find several new stable compositions and phases, especially in the…

Materials Science · Physics 2021-01-13 Roman Lucrezi , Christoph Heil

The complex crystal chemistry of elemental boron has led to numerous proposed structures with distinctive motifs as well as contradictory findings. Herein, evolutionary structure searches performed at 100 GPa have uncovered a series of…

Materials Science · Physics 2021-05-19 Katerina P. Hilleke , Eva Zurek , Tadashi Ogitsu , Shuai Zhang

Recently, Pei et al. (arXiv2105.13250) reported that ambient pressure ${\beta}$-MoB$_2$ exhibits a phase transition to ${\alpha}$-MoB$_2$ (space group: $P6/mmm$) at pressure P~70 GPa and this high-pressure phase is a high-temperature…

Superconductivity · Physics 2023-03-28 E. F. Talantsev

Metal borides have been considered as potential high-temperature superconductors since the discovery of record-holding 39 K superconductivity in bulk MgB2. In this work, we identified a superconducting yet thermodynamically stable F43m…

Superconductivity · Physics 2023-10-24 Xin Yang , Wenbo Zhao , Liang Ma , Wencheng Lu , Xin Zhong , Yu Xie , Hanyu Liu , Yanming Ma

We characterize the superconducting state of phase pure polycrystalline samples of the new layered superconductor MgB$_2$ by specific heat measurements in magnetic fields up to 9 T. The characteristic jump at the superconducting transition…

Superconductivity · Physics 2007-05-23 R. K. Kremer , B. J. Gibson , K. Ahn

Since the discovery of superconductivity in MgB2 (Tc ~ 39 K), the search for superconductivity in related materials with similar structures or ingredients has never stopped. Although about 100 binary borides have been explored, only few of…

The discovery of superconductivity in MgB$_2$ (\(T_c = 39\) K) \cite{nagamatsu2001superconductivity} established metal diborides (MB$_2$) as a promising class of conventional superconductors. Recent advances in fabrication techniques have…

Superconductivity · Physics 2026-04-08 Jakkapat Seeyangnok , Udomsilp Pinsook , Graeme J. Ackland

Motivated by advances in hydrogen-rich superconductors in the past decades, we conducted variable-composition structural searches in Mo-H binary system at high pressure. A new composition-pressure phase diagram of thermodynamically stable…

Superconductivity · Physics 2024-01-31 Aiqin Yang , Xiangru Tao , Yundi Quan , Peng Zhang

Using first-principles variable-composition evolutionary methodology, we explored the high-pressure structures of beryllium hydrides between 0 and 400 GPa. We found that BeH$_2$ remains the only stable compound in this pressure range. The…

Materials Science · Physics 2014-07-15 Shuyin Yu , Qingfeng Zeng , Artem R. Oganov , Chaohao Hu , Gilles Frapper , Litong Zhang

It is shown that the superconducting intermetallic compound MgB2 possesses a narrow, partly filled "superconducting band" with Wannier functions of special symmetry in its band structure. This result corroborates previous observations about…

Superconductivity · Physics 2011-03-03 Ekkehard Krüger

Superconductivity was found for a rhenium boride Re3B at Tc=4.7 K and for ReB2 with Tc in the range from 4.5 to 6.3 K depending on the boron concentrations. Both compounds have the structure different from that of the simple layered…

Superconductivity · Physics 2007-05-23 G. K. Strukova , V. F. Degtyareva , D. V. Shovkun , V. N. Zverev , V. M. Kiiko , A. M. Ionov , A. N. Chaika

We investigate the high-pressure behaviour of beryllium, magnesium and calcium difluorides using ab initio random structure searching and density functional theory (DFT) calculations, over the pressure range 0-70 GPa. Beryllium fluoride…

Materials Science · Physics 2017-03-01 J. R. Nelson , R. J. Needs , C. J. Pickard

Since the discovery of MgB2 with Tc=39K, various metal diborides of MB2 have been intensively studied to find possible conventional high-temperature superconductors. A possible 2D structure of the metal diboride has been shown to be in the…

Superconductivity · Physics 2024-12-19 Jakkapat Seeyangnok , Udomsilp Pinsook , Graeme John Ackland

Phase relations in the B-BN system have been studied ex situ and in situ at pressures 2-20 GPa and temperatures up to 2800 K. The evolution of topology of the B-BN phase diagram has been investigated up to 24 GPa using models of…

Materials Science · Physics 2018-04-20 Vladimir L. Solozhenko , Vladimir Z. Turkevich

We study the effects of pressure on the electron-phonon interaction in MgB_2 using density-functional-based methods. Our results show that the superconductivity in MgB_2 vanishes by 100 GPa, and then reappears at higher pressures. In…

Superconductivity · Physics 2009-11-11 Prabhakar P. Singh

The exploration of superconductivity dominated by structural units is of great interest in condense matter physics. MgB2, consisting of graphene-like B, becomes a typical representative of traditional superconductors. Phosphorus…

Superconductivity · Physics 2021-12-06 Xing Li , Xiaohua Zhang , Yong Liu , Guochun Yang

The electronic band structures of the new superconducting (with T_c up to 7.7K) ternary silicides M(A_{0.5}Si_{0.5})_2 (M= Ca, Sr, Ba; A= Al, Ga) in the AlB_2-type structure have been investigated using the full-potential LMTO method. The…

Superconductivity · Physics 2009-11-07 I. R. Shein , N. I. Medvedeva , A. L. Ivanovskii

A new two-dimensional material { Mg2B4C2, belonging to the family of the conventional superconductor MgB2, is theoretically predicted to exhibit superconductivity with critical temperature Tc estimated in the 47-48 K range (predicted using…