Absence of spin gap in the superconducting ladder compound Sr_2Ca_{12}Cu_{24}O_{41}

H. Mayaffre; P. Auban-Senzier; D. Jérome; D. Poilblanc; C. Bourbonnais; U. Ammerahl; G. Dhalenne; A. Revcolevschi

doi:10.1126/science.279.5349.345

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Absence of spin gap in the superconducting ladder compound Sr_2Ca_{12}Cu_{24}O_{41}

H. Mayaffre·P. Auban-Senzier·D. Jérome·D. Poilblanc·C. Bourbonnais·U. Ammerahl·G. Dhalenne·A. Revcolevschi

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Abstract

Transport and 63^Cu-NMR, Knight shift and T_1, measurements performed on the two-leg spin ladders of Sr_2Ca_{12}Cu_{24}O_{41} single crystals show a collapse of the gap in ladder spin excitations when superconductivity is stabilised under a pressure of 29 kbar. These results support the prediction made with exact diagonalisation techniques in two-leg isotropic t-J ladders of a transition between a low-doping spin gap phase and a gapless 1-D Tomonaga-Luttinger regime.

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H. Mayaffre, P. Auban-Senzier, D. Jérome, D. Poilblanc, C. Bourbonnais, U. Ammerahl, G. Dhalenne, A. Revcolevschi. 1997-10-07. Absence of spin gap in the superconducting ladder compound Sr_2Ca_{12}Cu_{24}O_{41}. https://doi.org/10.1126/science.279.5349.345

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