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arXiv · 0704.1161

The Fincher-Burke spin excitations and omega/T scaling in the insulating 5% Sr-doped La2CuO4

Wei Bao·Ying Chen·K. Yamada·A. T. Savici·P. L. Russo·J. E. Lorenzo·J. -H. Chung
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Abstract

Insulating La1.95Sr0.05CuO4 shares with superconducting cuprates the same Fincher-Burke-like spin excitations, which usually are observed in itinerant antiferromagnets. The local spectral function satisfies omega/T scaling above ~16 K for this incommensurate insulating cuprate. Together with previous results in commensurate insulating and incommensurate superconducting cuprates, these results further support the general scaling prediction for square-lattice quantum spin S=1/2 systems. The width of incommensurate peaks in La1.95Sr0.05CuO4 scales to a similar finite value as at optimal doping, strongly suggesting that they are similarly distant from a quantum critical point. They might both be limited to a finite correlation length by the partial spin-glass freezing.

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Wei Bao, Ying Chen, K. Yamada, A. T. Savici, P. L. Russo, J. E. Lorenzo, J. -H. Chung. 2007-10-23. The Fincher-Burke spin excitations and omega/T scaling in the insulating 5% Sr-doped La2CuO4. https://doi.org/10.1103/physrevb.76.180406

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