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arXiv · 0807.4890

Fermi surface of superconducting LaFePO determined by quantum oscillations

A. I. Coldea·J. D. Fletcher·A. Carrington·J. G. Analytis·A. F. Bangura·J. -H. Chu·A. S. Erickson·I. R. Fisher·N. E. Hussey·R. D. McDonald
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Abstract

We report extensive measurements of quantum oscillations in the normal state of the Fe-based superconductor LaFePO, (Tc ~ 6 K) using low temperature torque magnetometry and transport in high static magnetic fields (45 T). We find that the Fermi surface is in broad agreement with the band-structure calculations with the quasiparticle mass enhanced by a factor ~2. The quasi-two dimensional Fermi surface consist of nearly-nested electron and hole pockets, suggesting proximity to a spin/charge density wave instability.

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A. I. Coldea, J. D. Fletcher, A. Carrington, J. G. Analytis, A. F. Bangura, J. -H. Chu, A. S. Erickson, I. R. Fisher, N. E. Hussey, R. D. McDonald. 2008-10-19. Fermi surface of superconducting LaFePO determined by quantum oscillations. https://doi.org/10.1103/physrevlett.101.216402

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