Spin resonance peak in Na${}_x$CoO${}_2\cdot y$H${}_2$O superconductors: A probe of the pairing symmetry

Jian-Xin Li, Z. D. Wang

Motivated by the recent discovery of superconductivity in layered Na${}_x$CoO${}_2\cdot y$H${}_2$O compound, we investigate theoretically the spin dynamics in the superconducting s…