Unconventional Superconductivity in the 
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi>BiS</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>
-Based Layered Superconductor 
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi>NdO</mml:mi></mml:mrow><mml:mrow><mml:mn>0.71</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mrow><mml:mi mathvariant="no

Ota, Yuichi; Okazaki, Kozo; Yamamoto, Harukaze; Yamamoto, Takashi; Watanabe, S.; Chen, Chuangtian; Nagao, Masanori; Watauchi, Satoshi; Tanaka, Isao; Takano, Yoshihiko; Shin, Shik

doi:10.1103/physrevlett.118.167002

Cited by 60 publications

(44 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is consistent with the isotope effect; no isotope effect was observed for the LaO0.6F0.4Bi(S,Se)2 samples with 76 Se and 80 Se isotopes [31]. proposed by theoretical and experimental studies [28,29,32,39], may occur in the BiCh2-based system.…”

supporting

confidence: 83%

“…If this is valid, then the Tc increases when the phonon frequency decreases with the increase of the amplitude of the S1 vibration along the c-axis. proposed by theoretical and experimental studies [28,29,32,39], may occur in the BiCh2-based system.In conclusion, we investigated the crystal structure and anisotropic displacement parameters of REO0.5F0.5BiS2 with RE = La, Ce, Pr, and Nd, where bulk superconductivity is induced by substitutions with a smaller-radius RE, such as Pr or Nd. With the decrease of the RE 3+ ionic radius, the lattice constant a and in-plane Bi-S1 distance monotonically decreased, which generated the in-plane chemical pressure effect.…”

mentioning

confidence: 99%

mentioning

confidence: 99%

“…and RE-substituted REO0.5F0.5BiS2 systems [31][32][33], the universality revealed in this study could be employed to further understand the mechanisms of the superconductivity in the BiCh2-based superconductors.…”

mentioning

confidence: 99%

See 3 more Smart Citations

Evolution of Anisotropic Displacement Parameters and Superconductivity with Chemical Pressure in BiS₂-Based REO_0.5F_0.5BiS₂ (RE = La, Ce, Pr, and Nd)

et al. 2018

View full text Add to dashboard Cite

In order to understand the mechanisms behind the emergence of superconductivity by the chemical pressure effect in REO0.5F0.5BiS2 (RE = La, Ce, Pr, and Nd), where bulk superconductivity is induced by the substitutions with a smaller-radius RE, we performed synchrotron powder X-ray diffraction, and analyzed the crystal structure and anisotropic displacement parameters. With the decrease of the RE 3+ ionic radius, the in-plane disorder of the S1 sites significantly decreased, very similar to the trend observed in the Se-substituted systems: LaO0.5F0.5BiS2-xSex and Eu0.5La0.5FBiS2-xSex. Therefore, the emergence of bulk superconductivity upon the suppression of the in-plane disorder at the chalcogen sites is a universal scenario for the BiCh2-based superconductors. In addition, we indicated that the amplitude of vibration along the c-axis of the in-plane chalcogen sites may be related to the Tc in the BiCh2-based superconductors. . In addition, the observed temperature dependence of the electrical resistivity was not metallic-like; it showed a weakly localized behavior in LaO1-xFxBiS2, although band calculations suggested that the electron-doped LaO1-xFxBiS2 should be metal [4,5,12]. These results suggested that the doped electrons were localized by the effect of structural disorder.In order to induce bulk superconductivity in LaO1-xFxBiS2, high pressure effects can be employed.The application of an external pressure induces bulk superconductivity with a Tc of ~10 K [13][14][15]. In addition, samples annealed under a high pressure (~2 GPa) also exhibit bulk superconductivity with aTc of ~10 K [2,[16][17][18]. The emergence of bulk superconductivity and increase of Tc in the highpressure phase can be attributed to the structural phase transition from the tetragonal low-Tc phase to the monoclinic high-Tc phase [13].Another approach to induce bulk superconductivity in the LaO1-xFxBiS2 system is to introduce a chemical pressure by an isovalent substitution, such as Ch (Ch: S, Se) and/or RE site substitutions. In LaO0.5F0.5BiS2-xSex, the substitutions of Se for the S sites induces bulk superconductivity with a Tc of ~3.8 K [19,20]. Another isovalent substitution is the RE site substitution. With the decrease of the RE 3+ (mean) ionic radius in REO0.5F0.5BiS2, the BiS2 layer becomes compressed, in particular along the ab-plane direction, and bulk superconductivity is induced [21]. As the isovalent substitution does not significantly affect the carrier concentration, the structural optimization induces superconductivity in the Ch-and RE-substituted systems. In order to analyze the essential factor for the emergence of the superconductivity, we considered the commonality of the chemical pressure effects between the Ch-and RE substitutions, by introducing the concept of an in-plane chemical pressure [22].The emergence of the bulk superconductivity in the LaO0.5F0.5BiS2-xSex system was explained by the decrease in the in-plane disorder of the chalcogen sites with the increase of the Se content, which was detected thro...

show abstract

supporting

confidence: 83%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Evolution of Anisotropic Displacement Parameters and Superconductivity with Chemical Pressure in BiS₂-Based REO_0.5F_0.5BiS₂ (RE = La, Ce, Pr, and Nd)

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Previously, assuming spin fluctuations scenario and the presence of the disconnected Fermi surfaces for the small electron doping the d x y 2 2 --wave symmetry for the BiS 2 systems was obtained [12,30]. At the same time, recent ARPES experiments point towards strongly anisotropic superconducting gap [28], which would not agree with the simple spin-fluctuation mediated scenario with strong interband repulsion. Here, we concentrate on the more realistic situation of the weak spin fluctuations and analyze the potential Cooper-pairing instabilities for the case of disconnected Fermi surface pockets using the LAHA, developed previously and specially designed for the systems when the spin fluctuations are either intermediate or weak [29,36,37].…”

Section: Lindhard Response Functionmentioning

confidence: 96%

Spin–orbit coupling, minimal model and potential Cooper-pairing from repulsion in BiS₂-superconductors

et al. 2018

View full text Add to dashboard Cite

We develop the realistic minimal electronic model for recently discovered BiS 2 superconductors including the spin-orbit (SO) coupling based on the first-principles band structure calculations. Due to strong SO coupling, characteristic for the Bi-based systems, the tight-binding low-energy model necessarily includes p x , p y , and p z orbitals. We analyze a potential Cooper-pairing instability from purely repulsive interaction for the moderate electronic correlations using the so-called leading angular harmonics approximation. For small and intermediate doping concentrations we find the dominant instabilities to be d x y 2 2 --wave, and s ± -wave symmetries, respectively. At the same time, in the absence of the sizable spin fluctuations the intra and interband Coulomb repulsions are of the same strength, which yield the strongly anisotropic behavior of the superconducting gaps on the Fermi surface. This agrees with recent angle resolved photoemission spectroscopy findings. In addition, we find that the Fermi surface topology for BiS 2 layered systems at large electron doping can resemble the doped iron-based pnictide superconductors with electron and hole Fermi surfaces maintaining sufficient nesting between them. This could provide further boost to increase T c in these systems.

show abstract

Investigation of Superconducting Properties and Possible Nematic Superconductivity in Self‐Doped BiCh₂‐Based Superconductor CeOBiS_1.7Se_0.3

Kiyama

Hoshi

Goto

et al. 2021

Physica Rapid Research Ltrs

View full text Add to dashboard Cite

The superconducting properties and possible nematic superconductivity of the self‐doped BiCh2‐based (Ch: S, Se) superconductor CeOBiS1.7Se0.3 are investigated through measurements of the in‐plane anisotropy of magnetoresistance (MR). Single crystals of CeOBiS1.7Se0.3 are grown using a flux method. The single‐crystal structural analysis reveals that the crystal structure at room temperature is tetragonal (P4/nmm). Bulk superconductivity with a transition temperature of 3.3 K is observed through electrical resistivity and magnetization measurements. Investigation of the anisotropy of the upper critical field suggests relatively low anisotropy in the crystal compared to that of other BiCh2‐based superconductors. In the superconducting states of CeOBiS1.7Se0.3, a twofold symmetric in‐plane anisotropy of MR is observed, which indicates the in‐plane rotational symmetry breaking in the superconducting states of CeOBiS1.7Se0.3.

show abstract

Unconventional Superconductivity in the BiS2 -Based Layered Superconductor NdO0.71
Yuichi Ota¹,
Kozo Okazaki²,
Harukaze Yamamoto³
et al.

Cited by 60 publications

References 40 publications

Evolution of Anisotropic Displacement Parameters and Superconductivity with Chemical Pressure in BiS₂-Based REO_0.5F_0.5BiS₂ (RE = La, Ce, Pr, and Nd)

Evolution of Anisotropic Displacement Parameters and Superconductivity with Chemical Pressure in BiS₂-Based REO_0.5F_0.5BiS₂ (RE = La, Ce, Pr, and Nd)

Spin–orbit coupling, minimal model and potential Cooper-pairing from repulsion in BiS₂-superconductors

Investigation of Superconducting Properties and Possible Nematic Superconductivity in Self‐Doped BiCh₂‐Based Superconductor CeOBiS_1.7Se_0.3

Contact Info

Product

Resources

About

Unconventional Superconductivity in the BiS2 -Based Layered Superconductor NdO0.71Yuichi Ota1, Kozo Okazaki2, Harukaze Yamamoto3 et al.

Cited by 60 publications

References 40 publications

Evolution of Anisotropic Displacement Parameters and Superconductivity with Chemical Pressure in BiS2-Based REO0.5F0.5BiS2 (RE = La, Ce, Pr, and Nd)

Evolution of Anisotropic Displacement Parameters and Superconductivity with Chemical Pressure in BiS2-Based REO0.5F0.5BiS2 (RE = La, Ce, Pr, and Nd)

Spin–orbit coupling, minimal model and potential Cooper-pairing from repulsion in BiS2-superconductors

Investigation of Superconducting Properties and Possible Nematic Superconductivity in Self‐Doped BiCh2‐Based Superconductor CeOBiS1.7Se0.3

Contact Info

Product

Resources

About

Unconventional Superconductivity in the BiS2 -Based Layered Superconductor NdO0.71
Yuichi Ota¹,
Kozo Okazaki²,
Harukaze Yamamoto³
et al.

Evolution of Anisotropic Displacement Parameters and Superconductivity with Chemical Pressure in BiS₂-Based REO_0.5F_0.5BiS₂ (RE = La, Ce, Pr, and Nd)

Evolution of Anisotropic Displacement Parameters and Superconductivity with Chemical Pressure in BiS₂-Based REO_0.5F_0.5BiS₂ (RE = La, Ce, Pr, and Nd)

Spin–orbit coupling, minimal model and potential Cooper-pairing from repulsion in BiS₂-superconductors

Investigation of Superconducting Properties and Possible Nematic Superconductivity in Self‐Doped BiCh₂‐Based Superconductor CeOBiS_1.7Se_0.3