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arXiv · 0905.3305

Topological change of the Fermi surface in ternary iron-pnictides with reduced c/a ratio: A dHvA study of CaFe2P2

Amalia I. Coldea·C. M. J. Andrew·J. G. Analytis·R. D. McDonald·A. F. Bangura·J. -H. Chu·I. R. Fisher·A. Carrington
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Abstract

We report a de Haas-van Alphen effect study of the Fermi surface of CaFe2P2 using low temperature torque magnetometry up to 45 T. This system is a close structural analogue of the collapsed tetragonal non-magnetic phase of CaFe2As2. We find the Fermi surface of CaFe2P2 to differ from other related ternary phosphides in that its topology is highly dispersive in the c-axis, being three-dimensional in character and with identical mass enhancement on both electron and hole pockets (~1.5). The dramatic change in topology of the Fermi surface suggests that in a state with reduced (c/a) ratio, when bonding between pnictogen layers becomes important, the Fermi surface sheets are unlikely to be nested.

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Amalia I. Coldea, C. M. J. Andrew, J. G. Analytis, R. D. McDonald, A. F. Bangura, J. -H. Chu, I. R. Fisher, A. Carrington. 2009-05-20. Topological change of the Fermi surface in ternary iron-pnictides with reduced c/a ratio: A dHvA study of CaFe2P2. https://doi.org/10.1103/physrevlett.103.026404

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