2003/05/31 by Oskar Vafek, Zlatko Tesanovic
Physics and Astronomy · #cond-mat.supr-con #cond-mat.str-el
paper · pdf · doi:10.1103/physrevlett.91.237001
published as Phys. Rev. Lett. 91, 237001 (2003) · 5 pages; published version
arxiv created 2003/12/02 · arxiv updated 2009/11/30
We present finite temperature extension of the QED3 theory of underdoped cuprates. The theory describes nodal quasiparticles whose interactions with quantum proliferated vortex-antivortex pairs are represented by an emergent U(1) gauge field. Finite temperature introduces a scale beyond which the long wavelength fluctuations in the spatial components of vorticity are suppressed. As a result, the spin susceptibility of the pseudogap state is bounded by T2 at low T and crosses over to ∼ T at higher T, while the low-T electronic specific heat scales as T2, reflecting the thermodynamics of QED3. The Wilson ratio vanishes as T→ 0. This non-Fermi liquid behavior originates from two general principles: spin correlations induced by ``gauge'' interactions of quasiparticles and fluctuating vortices and the ``relativistic'' scaling of the T=0 fixed point.