Spin and charge response of phase fluctuating d-wave superconductors
Abstract
General theory of nodal d-wave quasiparticles coupled to regular and vortex fluctuations of the phase of the superconducting order parameter will be presented. The theory predicts a strong charge renormalization and vanishing superfluid density with underdoping. In the spin sector, the theory reduces to the QED3 [1] in the pseudogap state, and is related to the Thirring model in the superconducting state. At lowest energies spin response is predicted to be 'diagonally' incommensurate, with four peaks centered at the wave vectors that span between the nodes. With increase in energy, these four 'mother' peaks first overlap to produce the dominant response at four 'parallel' incommensurate wavevectors, and finally at the commensurate wavevector, giving birth to 'resonance'. At higher energies the resonance splits into four weak 'parallel' incommensurate peaks again with upward dispersion. Various details of the spin response will be discussed, and compared with the measurements on underdoped YBCO [2]. [1] I. F. Herbut, Phys. Rev. B, Phys. Rev. B 66. 094504 (2002). [2] I. F. Herbut and D. J. Lee, Phys. Rev. B 68. 104518 (2003).
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MARJ13013H