Resonant Raman scattering in mercurate single crystals

We report resonant electronic Raman scattering in optimally doped single layer HgBa2CuO4+delta (Hg-1201) and trilayer HgBa2Ca2Cu3O8+delta (Hg-1223) single crystals. Analysis of the B-1g and B-2g channels in the superconducting state of Hg-1201 advocates for a gap having d-wave symmetry. In addition a resonant study B-1g pair-breaking peak and the A(1g) peak suggests that the A(1g) peak is not directly related to the d-wave superconducting gap amplitude. Comparison with trilayer Hg-1223 demonstrates the universal behavior of this two energy scales in optimally doped cuprates. (C) 2004 Elsevier B.V. All rights reserved.