Electron–Phonon Coupling and Superconducting Critical Temperature of the YIr2Si2 and LaIr2Si2 High-Temperature Polymorphs from First-Principles

Billington, David P.; Nickau, Simon A C; Farley, Tom; Ward, Jack R.; Sperring, Rosie F.; Millichamp, Thomas E.; Ernsting, David; Dugdale, Stephen B

doi:10.7566/jpsj.83.044710

Cited by 8 publications

(5 citation statements)

References 24 publications

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“…This enables arising multi-band superconductivity with anisotropic properties (superconductivity within ab-planes). It is worth noting that analogous quasi-2D FS's were predicted for the YIr 2 Si 2 superconductor with the same crystal structure [41,42] and also for the isostructural AFM counterpart UPt 2 Si 2 [43]. Generally, such multi-band and quasi-2D FS's resemble those of Fe-based [44] or some Ni/Pd-based [45] superconductors, the latter with a dominating electron-like character of the FS sheets.…”

Section: Electronic Structuresupporting

confidence: 55%

Search for unconventional superconductors among the YTE₂Si₂compounds (TE = Cr, Co, Ni, Rh, Pd, Pt)

Pikul

Samsel‐Czekała

Chajewski

et al. 2017

J. Phys.: Condens. Matter

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Motivated by the recent discovery of exotic superconductivity in YFeGe we undertook reinvestigation of formation and physical properties of yttrium-based 1:2:2 silicides. Here we report on syntheses and crystal structures of the YTE Si compounds with TE = Cr, Co, Ni, Rh, Pd and Pt, and their low-temperature physical properties measurements, supplemented by results of fully relativistic full-potential local-orbital minimum basis band structure calculations. We confirm that most of the members of that family crystallize in a tetragonal ThCrSi-type structure (space group I4/mmm) and have three-dimensional Fermi surface, while only one of them (YPtSi) forms with a closely-related primitive CaBeGe-type unit cell (space group P4/nmm) and possess quasi-two-dimensional Fermi surface sheets. Physical measurements indicated that BCS-like superconductivity is observed only in YPtSi (T = 1.54 K) and YPdSi (T = 0.43 K), while no superconducting phase transition was found in other systems at least down to 0.35 K. Thermal analysis showed no polymorphism in both superconducting phases. No clear relation between the superconductivity and the crystal structure (and dimensionality of the Fermi surface) was observed.

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Section: Electronic Structuresupporting

confidence: 55%

Search for unconventional superconductors among the YTE₂Si₂compounds (TE = Cr, Co, Ni, Rh, Pd, Pt)

Pikul

Samsel‐Czekała

Chajewski

et al. 2017

J. Phys.: Condens. Matter

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“…These value had been confirmed after screening its value in several compounds which always produced cutoff wave function around 40-60 Ry. This value also agree with previous studies which used 40 and 400 Ry for wave function and charge-density respectively when investigating the superconducting critical temperature of the YIr 2 Si 2 and LaIr 2 Si 2 , and also a theoretical investigation of ThCr 2 Si 2 -type Pd-based superconductors 16,17 . The accurate calculation of electron phonon coupling is very crucial problem since it needs accurate structure and the Eliashberg function of double delta over the Fermi surface which needs to be done with a high numerical accuracy 18 .…”

Section: Methodssupporting

confidence: 91%

“…From the Table I provided, the experimental data showed a good agreement with GGA functional. Several studied also used GGA functional instead of LDA 16 . Noted, this is a well known problem in LDA functional which tends to overbind while GGA is underbind the structure.…”

Section: Methodsmentioning

confidence: 99%

“…From these equations, the main factors effect the critical temperature (T c ) are ω ln and λ while for µ * , it is well known that its value is considered physically reasonable as an adjustable parameters around 0.1 until 0.2 12,16,24 . The electronphonon coupling constant λ is formalized as integral of averaged coupling strength between the electrons at fermi level and the phonon energy ω (α 2 F(ω)) described by following equation [25][26][27][28] .…”

Section: Methodsmentioning

confidence: 99%

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First Principles Calculations of Superconducting Critical Temperature of ThCr$_2$Si$_2$-Type Structure

Sinaga¹,

Utimula²,

Nakano³

et al. 2019

Preprint

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High critical temperature (T c ) superconductor has a great potential in many industrial applications. However, discovering a compound having high T c is still remaining a big challenge for experimental approach due to time-consuming and high cost. In this paper, we investigated the critical temperature (T c ) of several compounds of ThCr 2 Si 2 -type structure (space group I4/mmm) since some of them had already been investigated and trusted as the potential candidates for superconductivity. First principle calculation was performed to compute the critical temperature (T c ) based on allen-dynes equation modification of McMillian formula. In order to confirm our calculation scheme, we compared our result with compounds which had been experimentally determined obtained from NI MS database. The result showed a very good agreement with experimental data. Based on this scheme, finally, we found ThCu 2 Si 2 and ThAu 2 Si 2 which were most likely to exhibit a superconductivity around 3.88 K and 4.27. Since, these compounds have not been studied experimentally, then we futher investigated their electronic properties showing non-negative phonons which indicate the dynamical stability of the compounds at ambient condition. Band structure and DOS analysis showed metallic nature where the highest contributor come from d-orbital of rare-earth element and p-orbital of Si emerging a mixture of covalent, ionic and metallic bonds exists in both the compounds. Finally, we calculated the electron phonon coupling coefficient showing a quite large different (27%) leading to the increment of T c , however, both of compounds possess three dimensional electron-like and hole-like multi-band fermi surface which is related to the phonon mediated which is still under electron-phonon mediated superconductivity. keywords : superconductivity, ThCr 2 Si 2 -type structure, ThCu 2 Si 2 , ThAu 2 Si 2 , critical temperature

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“…In addition, Shein and Ivanovskii [4][5][6][7] studied the structural, elastic, magnetic, and electronic properties of SrPt2As2, KCo2Se2, KFe2AsSe, and KFeAgTe2 polymorphs with ThCr2Si2-type structures by the first principles methods. Billington et al studied electron-phonon coupling and critical temperature in YIr2Si2 and LaIr2Si2 High-Tc superconducting polymorphs [8].…”

Section: Introductionmentioning

confidence: 99%

The Electronic, Optical and Lattice Dynamical Properties of YIr2X2 (X=Si, Ge) Polymorphs: A DFT Study

Bi̇çer

Sürücü

2018

Aksaray University Journal of Science and Engineering

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The electronic, optical, and lattice-dynamical properties of YIr2X2(X=Si, Ge) compounds are investigated using the first-principles plane-wave pseudopotential method within the GGA approximation. In particular, the lattice constant, density of state, dielectric constant, refractive index and phonon properties are calculated and discussed. The calculated lattice parameters are in good agreement with previous experimental and theoretical data, whereas the formation enthalpies of the compounds are -1.149 and -0.841 eV/f.u. indicating that the compounds are stable in the body-centered tetragonal structure. In addition, real and imaginary parts of the static dielectric constant are 52.26 and 72.68, respectively.

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Electron–Phonon Coupling and Superconducting Critical Temperature of the YIr₂Si₂ and LaIr₂Si₂ High-Temperature Polymorphs from First-Principles

Cited by 8 publications

References 24 publications

Search for unconventional superconductors among the YTE₂Si₂compounds (TE = Cr, Co, Ni, Rh, Pd, Pt)

Search for unconventional superconductors among the YTE₂Si₂compounds (TE = Cr, Co, Ni, Rh, Pd, Pt)

First Principles Calculations of Superconducting Critical Temperature of ThCr$_2$Si$_2$-Type Structure

The Electronic, Optical and Lattice Dynamical Properties of YIr2X2 (X=Si, Ge) Polymorphs: A DFT Study

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Electron–Phonon Coupling and Superconducting Critical Temperature of the YIr2Si2 and LaIr2Si2 High-Temperature Polymorphs from First-Principles

Cited by 8 publications

References 24 publications

Search for unconventional superconductors among the YTE2Si2compounds (TE = Cr, Co, Ni, Rh, Pd, Pt)

Search for unconventional superconductors among the YTE2Si2compounds (TE = Cr, Co, Ni, Rh, Pd, Pt)

First Principles Calculations of Superconducting Critical Temperature of ThCr$_2$Si$_2$-Type Structure

The Electronic, Optical and Lattice Dynamical Properties of YIr2X2 (X=Si, Ge) Polymorphs: A DFT Study

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Product

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About

Electron–Phonon Coupling and Superconducting Critical Temperature of the YIr₂Si₂ and LaIr₂Si₂ High-Temperature Polymorphs from First-Principles

Search for unconventional superconductors among the YTE₂Si₂compounds (TE = Cr, Co, Ni, Rh, Pd, Pt)

Search for unconventional superconductors among the YTE₂Si₂compounds (TE = Cr, Co, Ni, Rh, Pd, Pt)