Superconductivity of the $Sr_2 Ca_{12} Cu_{24} O_{41}$ spin ladder system: Are the superconducting pairing and the spin-gap formation of the same origin?

Naoki Fujiwara

doi:10.1103/PhysRevLett.90.137001

paper

Superconductivity of the $S r_{2} C a_{12} C u_{24} O_{41}$ spin ladder system: Are the superconducting pairing and the spin-gap formation of the same origin?

arXiv:cond-mat/0303278 · doi:10.1103/PhysRevLett.90.137001

Abstract

Pressure-induced superconductivity in a spin-ladder cuprate Sr $_{2}$ Ca $_{12}$ Cu $_{24}$ O $_{41}$ has not been studied on a microscopic level so far although the superconductivity was already discovered in 1996. We have improved high-pressure technique with using a large high-quality crystal, and succeeded in studying the superconductivity using $^{63}$ Cu nuclear magnetic resonance (NMR). We found that anomalous metallic state reflecting the spin-ladder structure is realized and the superconductivity possesses a s-wavelike character in the meaning that a finite gap exists in the quasi-particle excitation: At pressure of 3.5GPa we observed two excitation modes in the normal state from the relaxation rate $T_{1}^{- 1}$ . One gives rise to an activation-type component in $T_{1}^{- 1}$ , and the other $T$ -linear component linking directly with the superconductivity. This gapless mode likely arises from free motion of holon-spinon bound states appearing by hole doping, and the pairing of them likely causes the superconductivity.

to be published in Phys. Rev. Lett

Superconductivity of the $S r_{2} C a_{12} C u_{24} O_{41}$ spin ladder system: Are the superconducting pairing and the spin-gap formation of the same origin?

Abstract

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Cited by in corpus (21)

Superconductivity of the Sr2​Ca12​Cu24​O41​ spin ladder system: Are the superconducting pairing and the spin-gap formation of the same origin?

Abstract

References in corpus (5)

Cited by in corpus (21)

Superconductivity of the $S r_{2} C a_{12} C u_{24} O_{41}$ spin ladder system: Are the superconducting pairing and the spin-gap formation of the same origin?