Anisotropy of the dc conductivity due to orbital-selective spin fluctuations in the nematic phase of iron superconductors

Fernández-Martín, Raquel; Fanfarillo, Laura; Valenzuela, B.

doi:10.1103/physrevb.99.155117

Cited by 10 publications

(10 citation statements)

References 63 publications

(112 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…just above T c ). It is worth noting that a recent approach based on orbital-selective spin fluctuations 24,32,33 can explain the emergence of the orbital ordering, as well as of the anisotropy in the scattering rate and plasma frequency, revealing the spin-orbital interplay and in broad qualitative agreement with our findings. Fig.…”

Section: Discussionsupporting

confidence: 89%

“…The anisotropic optical response at MIR energy scales unfolded here generally relates to anisotropic interband transitions, which shape the joint-density-of-states, directly imaged by σ 1 (ω). Such an anisotropy originates from the split of the relevant bands of the order of only a few tens of meV 27 and highlights the important role of the orbital degrees of freedom 24,[27][28][29][30][31][32][33][34][35][36] . Moreover, its change of sign ( Fig.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Ingredients for the electronic nematic phase in FeSe revealed by its anisotropic optical response

et al. 2018

View full text Add to dashboard Cite

The origin of the anisotropy in physical quantities related to a symmetry-broken (nematic) electronic state is still very much debated in high-temperature superconductors. FeSe at ambient pressure undergoes a structural, tetragonal-to-orthorhombic phase transition at Ts 90 K without any magnetic ordering on further cooling, which leads to an ideal electronic nematicity. Our unprecedented optical results provide evidence that the low-energy excitation spectrum in the nematic phase is shaped by an important interplay of the anisotropic Drude weight and scattering rate. In the zero-frequency limit though, the temperature dependence of the anisotropic scattering rate plays the dominant role and, combined with the nematic order parameter as evinced from the high energy optical response, accounts for the anisotropic dc resistivity. This favours the scattering by anisotropic spin fluctuations as the prominent candidate in governing the properties of the nematic phase.

show abstract

Section: Discussionsupporting

confidence: 89%

Section: Discussionmentioning

confidence: 99%

Ingredients for the electronic nematic phase in FeSe revealed by its anisotropic optical response

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Notice that even below T s , the large elliptical Z pocket, k x F = 0.10Å −1 and k y F = 0.15 A −1 , retains a marked yz character at θ = 0 in agreement with the ARPES measurements 24,25,28 . Moreover given this band structure, the inclusion of a finite spinorbit coupling does not lead to any significant change, and the u Z , v Z , factors defined as Eq.s (33), (39) scale approximately as cos θ and sin θ even below T s .…”

Section: Supplementary Note 3: Model Parameters For Fesementioning

confidence: 92%

“…19. The list of the band parameters appearing in Eq.s (31), (36) and used in the calculations are given in The u, v, factors defined by Eq.s (33), (39), computed using the above set of parameters, are shown in Fig. 2 of the main text.…”

Section: Supplementary Note 3: Model Parameters For Fesementioning

confidence: 99%

See 1 more Smart Citation

Nematic pairing from orbital-selective spin fluctuations in FeSe

2018

Self Cite

View full text Add to dashboard Cite

FeSe is an intriguing iron-based superconductor. It presents an unusual nematic state without magnetism and can be tuned to increase the critical superconducting temperature. Recently it has been observed a noteworthy anisotropy of the superconducting gaps. Its explanation is intimately related to the understanding of the nematic transition itself. Here we show that the spin-nematic scenario driven by orbital-selective spin-fluctuations provides a simple scheme to understand both phenomena. The pairing mediated by anisotropic spin modes is not only orbital selective but also nematic, leading to stronger pair scattering across the hole and X electron pocket. The delicate balance between orbital ordering and nematic pairing points also to a marked kz dependence of the hole-gap anisotropy.

show abstract

Strain derivative of thermoelectric properties as a sensitive probe for nematicity

et al. 2021

View full text Add to dashboard Cite

The nematic instability is an undebatable ingredient of the physics of iron-based superconductors. Yet, its origin remains enigmatic as it involves a fermiology with an intricate interplay of lattice-, orbital-, and spin degrees of freedom. It is well known that thermoelectric transport is an excellent probe for revealing even subtle signatures of instabilities and pertinent fluctuations. In this paper, we report a strong response of the thermoelectric transport properties of two underdoped 1111 iron-based superconductors to a vanishingly small strain. By introducing the strain derivative of the Seebeck and the Nernst coefficients, we provide a description of the nematic order parameter, proving the existence of an anisotropic Peltier-tensor beside an anisotropic conductivity tensor. Our measurements reveal that the transport nematic phenomenology is the result of the combined effect of both an anisotropic scattering time and Fermi surface distortions, pointing out that in a realistic description, abreast of the spin fluctuations also the orbital character is a fundamental ingredient. In addition, we show that nematic fluctuations universally relax in a Curie–Weiss fashion above TS in all the elasto-transport measurements and we provide evidences that nematicity must be band selective.

show abstract

Anisotropy of the dc conductivity due to orbital-selective spin fluctuations in the nematic phase of iron superconductors

Cited by 10 publications

References 63 publications

Ingredients for the electronic nematic phase in FeSe revealed by its anisotropic optical response

Ingredients for the electronic nematic phase in FeSe revealed by its anisotropic optical response

Nematic pairing from orbital-selective spin fluctuations in FeSe

Strain derivative of thermoelectric properties as a sensitive probe for nematicity

Contact Info

Product

Resources

About