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arXiv · 1103.4178

Direct observation of multiple spin zeroes in the underdoped high temperature superconductor YBa2Cu3O6+x

Suchitra E. Sebastian·N. Harrison·M. M. Altarawneh·F. F. Balakirev·C. H. Mielke·Ruixing Liang·D. A. Bonn·W. N. Hardy·G. G. Lonzarich
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Abstract

We report the direct observation of multiple `spin zeroes' in angle-dependent magnetic quantum oscillations measured up to 85T in YBa2Cu3O6+x, at which the amplitude falls to a deep minimum accompanied by a phase inversion of the measured quantum oscillations, enabling the product of the effective mass and effective g-factor m*g* to be tightly constrained. We find an evolution of the location of the spin zeros with applied magnetic field, and suggest that this effect and the absence of a spin zero at low angles can be produced by more than one Fermi surface component, and an effective g-factor with a subtle anisotropy between in-plane and out-of-plane crystalline directions.

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Suchitra E. Sebastian, N. Harrison, M. M. Altarawneh, F. F. Balakirev, C. H. Mielke, Ruixing Liang, D. A. Bonn, W. N. Hardy, G. G. Lonzarich. 2011-03-22. Direct observation of multiple spin zeroes in the underdoped high temperature superconductor YBa2Cu3O6+x. https://arxiv.org/abs/1103.4178

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