Sum rules and energy scales in the high-temperature superconductor YBa2Cu3O6+x

Abstract

The Ferrell-Glover-Tinkham (FGT) sum rule has been applied to the temperature dependence of the in-plane optical conductivity of optimally-doped YBa_2Cu_3O_{6.95} and underdoped YBa_2Cu_3O_{6.60}. Within the accuracy of the experiment, the sum rule is obeyed in both materials. However, the energy scale ω_c required to recover the full strength of the superfluid ρ_s in the two materials is dramatically different; ω_c \simeq 800 cm^{-1} in the optimally doped system (close to twice the maximum of the superconducting gap, 2Δ_0), but ω_c \gtrsim 5000 cm^{-1} in the underdoped system. In both materials, the normal-state scattering rate close to the critical temperature is small, Γ< 2Δ_0, so that the materials are not in the dirty limit and the relevant energy scale for ρ_s in a BCS material should be twice the energy gap. The FGT sum rule in the optimally-doped material suggests that the majority of the spectral weight of the condensate comes from energies below 2Δ_0, which is consistent with a BCS material in which the condensate originates from a Fermi liquid normal state. In the underdoped material the larger energy scale may be a result of the non-Fermi liquid nature of the normal state. The dramatically different energy scales suggest that the nature of the normal state creates specific conditions for observing the different aspects of what is presumably a central mechanism for superconductivity in these materials.

arXiv commentRevTeX 4 file, 9 pages with 7 embedded eps figures

References in corpus (24)

• The pseudogap in high-temperature superconductors: an experimental survey
• Heat Transport in a Strongly Overdoped Cuprate: Fermi Liquid and Pure d-wave BCS Superconductor
• Predominantly Superconducting Origin of Large Energy Gaps in Underdoped Bi2Sr2CaCu2O8-d from Tunneling Spectroscopy
• Superconducting Gap and Strong In-Plane Anisotropy in Untwinned YBa2Cu3O7-d
• Pairing in cuprates from high energy electronic states
• Absence of a pseudogap in the in-plane infrared response of Bi2Sr2CaCu2O(8+d)
• Observation of out-of-phase bilayer plasmons in YBa_2Cu_3O_7-delta
• Anomalies of the infrared-active phonons in underdoped YBCO as an evidence for the intra-bilayer Josephson effect
• Pseudogaps in Underdoped Cuprates
• Frustrated kinetic energy, the optical sum rule, and the mechanism of superconductivity
• Optical phonons along the c axis of YBa_2Cu_3O_{6+x}, for x=0.5 -> 0.95
• Interplane Transport and Superfluid Density in Layered Superconductors
• Global trends in the interplane penetration depth of layered superconductors
• Do electrons change their c-axis kinetic energy upon entering the superconducting state?
• Quasiparticle Formation and Optical Sum Rule Violation in Cuprate Superconductors
• The anomaly of the oxygen bond-bending mode at 320 cm${}^{-1}$ and the additional absorption peak in the c-axis infrared conductivity of underdoped YBa${}_2$Cu${}_3$O${}_{7-\delta }$ single crystals revisited by ellipsometricmeasurements
• Sum rules and electrodynamics of high-Tc cuprates in the pseudogap state
• Spin-Charge Separation is the Key to the High T_c Cuprates
• Where is 99% of the condensation energy of Tl_2Ba_2CuO_y coming from?
• Correlation between the Josephson coupling energy and the condensation energy in bilayer cuprate superconductors
• Condensation energy in strongly coupled superconductors
• Condensation Energy and High Tc Superconductivity
• The differential sum rule for the relaxation rate in the cuprates
• The Pseudogap Challenge: Understanding the ab-Plane AC Conductivity below Tc

Cited by in corpus (42)

• Electrodynamics of Correlated Electron Materials
• Probing superconducting energy gap from infrared spectroscopy on a Ba${}_{0.6}$K${}_{0.4}$Fe${}_2$As${}_2$ single crystal with T${}_c$=37 K
• Doping dependent optical properties of Bi2Sr2CaCu2O8+d
• Electrodynamics of the Nodal Metal in Weakly Doped High-$T_c$ Cuprates
• Energetic balance of the superconducting transition across the BCS-Bose E instein crossover in the attractive Hubbard model
• Kinetic energy change with doping upon superfluid condensation in high temperature superconductors
• Scaling of the superfluid density in high-temperature superconductors
• Temperature dependence of the optical spectral weight in the cuprates: Role of electron correlations
• Frequency-dependent Thermal Response of the Charge System and Restricted Sum Rules in La(2-x)Sr(x)CuO(4)
• The in-plane electrodynamics of the superconductivity in Bi2Sr2CaCu2O8+d: energy scales and spectral weight distribution
• Optical Conductivity of the t-J model within Cluster Dynamical Mean Field Theory
• Kinetic-energy driven superconductivity in cuprate superconductors
• Optical and Raman spectroscopy studies on Fe-based superconductors
• Ward identity and optical-conductivity sum rule in the d-density wave state
• In-plane optical conductivity of La${}_{2-x}$Sr${}_x$CuO${}_4$: Reduced superconducting condensate and residual Drude-like response
• Non-BCS behavior of optical properties across the cuprate phase diagram
• Infrared Signature of the Superconducting State in Pr(2-x)Ce(x)CuO(4)
• Optical Integral in the Cuprates and the Question of Sum Rule Violation
• Optical-conductivity sum rule in cuprates and unconventional charge density waves: a short review
• Thermodynamics of an Exactly Solvable Model for Superconductivity in a Doped Mott Insulator
• Optical sum increase due to electron undressing
• Infrared properties of Mg${}_{1-x}$Al${}_x($B${}_{1-y}$C${}_y$)${}_2$ single crystals in the normal and superconducting state
• Optical Sum Rule in Finite Bands
• Effect of orbital currents on the restricted optical sum rule
• Optical sum rule anomalies in the cuprates: interplay between strong correlation and electronic bandstructures
• Kinetic Energy, Condensation Energy, Optical Sum Rule and Pairing Mechanism in High-Tc Cuprates
• Interpretation of the in-plane infrared response of the high-Tc cuprate superconductors involving spin fluctuations revisited
• Optical sum rule in metals with a strong interaction
• Optical Integral and Sum Rule Violation
• Investigation of Precursor Superconducting State in YBa${}_2$Cu${}_3$O${}_{7-\delta }$ through In-plane Optical Spectroscopy
• Optical spectral weight distribution in d-wave superconductors
• Temperature Dependence of the Conductivity Sum Rule in the Normal State due to Inelastic Scattering
• Pseudogap Phase: Exchange Energy Driven vs. Kinetic Energy Driven
• The spin resonance and high frequency optical properties of the cuprates
• Strange metal from incoherent bosons
• Unravelling the mechanism of the semiconducting-like behavior and its relation to superconductivity in (CaFe${}_{1-x}$Pt${}_x$As)${}_{10}$Pt${}_3$As${}_8$
• Sum rules, plasma frequencies and Hall phenomenology in holographic plasmas
• Pseudogap and charge dynamics in doped cuprates
• Stripe-Like Inhomogeneities, Spectroscopies, Pairing, and Coherence in the High-Tc Cuprates
• Effect of the pseudogap on the infrared response in cuprate superconductors
• Electronic structure in underdoped cuprates due to the emergence of a pseudogap
• Particular type of gap in the spectrum of multiband superconductors