Disentangling the role of bond lengths and orbital symmetries in controlling $T_c$ in YBa${}_2$Cu${}_3$O${}_7$

Abstract

Optimally doped YBCO (YBa${}_2$Cu${}_3$O${}_7$) has a high critical temperature, at 92 K. It is largely believed that Cooper pairs form in YBCO and other cuprates because of spin fluctuations, the issue and the detailed mechanism is far from settled. In the present work, we employ a state-of-the-art \emph{ab initio} ability to compute both the low and high energy spin fluctuations in optimally doped YBCO. We benchmark our results against recent inelastic neutron scattering and resonant inelastic X-ray scattering measurements. Further, we use strain as an external parameter to modulate the spin fluctuations and superconductivity. We disentangle the roles of Barium-apical Oxygen hybridization, the interlayer coupling and orbital symmetries by applying an idealized strain, and also a strain with a fully relaxed structure. We show that shortening the distance between Cu layers is conducive for enhanced Fermi surface nesting, that increases spin fluctuations and drives up $T_c$. However, when the structure is fully relaxed electrons flow to the d${}_{z^2}$ orbital as a consequence of a shortened Ba-O bond which is detrimental for superconductivity

5 pages, 4 figures

References in corpus (8)

• Quantum Monte Carlo Impurity Solver for Cluster DMFT and Electronic Structure Calculations in Adjustable Base
• Quasiparticle self-consistent $GW$ method; a basis for the independent-particle approximation
• Strength of the Spin-Fluctuation-Mediated Pairing Interaction in a High-Temperature Superconductor
• Two-Orbital Model Explains the Higher Transition Temperature of the Single-Layer Hg-Cuprate Superconductor Compared to That of the La-Cuprate Superconductor
• Magnetic Excitations and their energy change available to Superconducting Condensation in Optimally Doped YBa${}_2$Cu${}_3$O${}_{6.95}$
• Electron-Phonon-Driven Three-Dimensional Metallicity in an Insulating Cuprate
• Controlling T${}_c$ through band structure and correlation engineering in collapsed and uncollapsed phases of iron arsenides
• Role of nematicity in controlling spin fluctuations and superconducting Tc in bulk FeSe

Cited by in corpus (1)

• Interfacial and thickness effects in La${}_{2/3}$Sr${}_{1/3}$MnO${}_3$/YBa${}_2$Cu${}_3$O${}_7$ superlattices