Universal scaling behavior of pseudogap with doping in high Tc cuprates; temperature and doping dependence of spectral intensity

TL;DR

This paper uses an improved SU(2) slave-boson approach to reveal universal doping-dependent scaling laws of the pseudogap in high Tc cuprates, explaining spectral features and the sharpening of quasiparticle peaks below Tc.

Contribution

It introduces a novel theoretical analysis demonstrating universal doping scaling of pseudogap ratios and explains spectral features in high Tc cuprates.

Findings

Universal hyperbolic scaling of pseudogap to Tc with doping, $rac{2 riangle_0}{k_B T_c} o x^{-eta}$

Near doping independence of pseudogap to $T^*$ ratio, $rac{2 riangle_0}{k_B T^*} ext{~constant}$

Sharpening of quasiparticle peaks below Tc attributed to holon pair Bose condensation.

Abstract

Based on our improved SU(2) slave-boson approach (Phys. Rev. B 64, 052501(2001)) to the t-J Hamiltonian, we report a scaling behavior of pseudogap with doping and the temperature and doping dependence of spectral functions. In addition we discuss the cause of hump and quasi-particle peak in the observed spectral functions of high Tc cuprates. It is demonstrated that the sharpening of the observed quasi-particle peak below Tc is attributed to the bose condensation of holon pair. From the computed ratios of pseudogap $\Delta_0$ to both the superconducting temperature Tc and the pseudogap temperature $T^*$ as a function of hole doping concentration x, we find that there exists a universal scaling of these ratios with doping, that is, the hyperbolic scaling behavior of the former, $\frac{2 \Delta_0}{k_B T_c} \sim x^{-\alpha}$ with $\alpha \sim 2$ and near doping independence of the latter, $\frac{2 \Delta_0}{k_B T^*} \approx 4 \sim 6$ are found.