Effects of Ca substitution on quasi-acoustic sliding modes in Sr${}_{14-x}$Ca${}_x$Cu${}_{24}$O${}_{41}$

Abstract

The low energy lattice dynamics of the quasi-periodic spin-ladder cuprate Sr${}_{14-x}$Ca${}_x$Cu${}_{24}$O${}_{41}$ are investigated using terahertz frequency synchrotron radiation. A high density of low-lying optical excitations are present in the 1-3 THz energy range, while at least two highly absorbing excitations stemming from rigid acoustic oscillations of the incommensurate chain and ladder sublattices, are observed at sub-terahertz frequencies. The effects of Ca substitution on the sub-terahertz quasi-acoustic sliding mode gaps is investigated using coherent synchrotron radiation. Analysis of the results suggest increasing substitution of Sr for Ca is accompanied by a transfer of spectral weight between sliding modes associated with different chain-ladder dynamics. The observation is consistent with a transfer of hole charges from the chains to the ladders and modification of the sublattice dimensions following Ca substitution. The results are discussed in context to the significance of low-lying vibrational dynamics and electron-phonon coupling in the superconducting state of certain quasi-periodic systems.

References in corpus (31)

• The Puzzle of High Temperature Superconductivity in Layered Iron Pnictides and Chalcogenides
• Experiments on Ladders Reveal a Complex Interplay between a Spin-Gapped Normal State and Superconductivity
• The Spin Dynamics of the Spin Ladder, Dimer Chain Material Sr14Cu24O41
• Hole crystallization in the spin ladder of Sr14Cu24O41
• Pressure-induced and Composition-induced Structural Quantum Phase Transition in the Cubic Superconductor (Sr/Ca)_3Ir_4Sn_{13}
• Charge Nematicity and Electronic Raman Scattering in Iron-based Superconductors
• Sliding Density-Wave in Sr_{14}Cu_{24}O_{41} Ladder Compounds
• Hole distribution for (Sr,Ca,Y,La)_14 Cu_24 O_41 ladder compounds studied by x-ray absorption spectroscopy
• Suppression of the charge-density-wave state in Sr_14Cu_24O_41 by calcium doping
• Quasi-two-dimensional hole ordering and dimerized state in the CuO2-chain layers in Sr14Cu24O41
• Charge-density wave formation in Sr_{14}Cu_{24}O_{41}
• Electronic structure and phonon instabilities in the vicinity of the structural transition and superconductivity of (Sr,Ca)${}_3$Ir${}_4$Sn${}_{13}$
• Optical Properties of the Spin-Ladder Compound Sr_{14}Cu_{24}O_{41}
• Far-infrared spectroscopy of spin excitations and Dzyaloshinskii-Moriya interactions in a Shastry-Sutherland compound SrCu${}_2$(BO${}_3$)$_2
• Evidence of a structural quantum critical point in (Ca${}_x$Sr${}_{1-x}$)${}_3$Rh${}_4$Sn${}_{13}$ from a lattice dynamics study
• Variable-range hopping conductivity in the copper-oxygen chains of La_3Sr_3Ca_8Cu_24O_41
• Weak coupling of pseudoacoustic phonons and magnon dynamics in incommensurate spin ladder compound Sr14Cu24O41
• Anisotropic Charge Modulation in Ladder Planes of Sr_14-xCa_xCu_24O_41
• Structural Evolution of One-dimensional Spin Ladder Compounds Sr14-xCaxCu24O41 with Ca doping and Related Hole Redistribution Evidence
• Charge order induced sharp Raman peak in Sr_14Cu_24O_41
• Superconductivity of Bi-III phase of elemental Bismuth: insights from Muon-Spin Rotation and Density Functional Theory
• Boson peak in overdoped manganites La_{1-x}Ca_{x}MnO_{3}
• Phononic gaps in the charged incommensurate planes of Sr14Cu24O41
• Spin gap evolution upon Ca doping in the spin ladder series $S{r}_{14-x}C{a}_{x}C{u}_{24}{O}_{41}$ by inelastic neutron scattering
• On the peak in the far-infrared conductivity of strongly anisotropic cuprates
• Effects of Superconductivity and Charge Order on the sub-Terahertz reflectivity of La${}_{1.875}$Ba${}_{0.125-y}$Sr${}_y$CuO${}_4$
• Macroscopic Quantum Coherence of the Spin Triplet in the Spin-Ladder Compound Sr14Cu24O41
• Optical spectroscopy of pure and doped CuGeO3
• Charge density waves in Sr_14-xCa_xCu_24O_41: electron correlations vs. structural effects
• Spin dynamics of edge-sharing spin chains in SrCa13Cu24O41
• Magneto-optic far-infrared study of Sr${}_{14}$Cu${}_{24}$O${}_{41}$: triplet excitations in chains