The evolution of the Fermi surface of CeRh1−xCoxIn5 was studied as a function of Co concentration x via measurements of the de Haas-van Alphen effect. By measuring the angular dependence of quantum oscillation frequencies, we identify a Fermi surface sheet with f-electron character which undergoes an abrupt change in topology as x is varied. Surprisingly, this reconstruction does not occur at the quantum critical concentration xc, where antiferromagnetism is suppressed to T=0. Instead we establish that this sudden change occurs well below xc, at the concentration x ~ 0.4 where long range magnetic order alters its character and superconductivity appears. Across all concentrations, the cyclotron effective mass of this sheet does not diverge, suggesting that critical behavior is not exhibited equally on all parts of the Fermi surface.
@article{arxiv.0803.4424,
title = {Fermi Surface Reconstruction in CeRh$_{1-x}$Co$_{x}$In$_{5}$},
author = {Swee K. Goh and Johnpierre Paglione and Mike Sutherland and E. C. T. O'Farrell and C. Bergemann and T. A. Sayles and M. B. Maple},
journal= {arXiv preprint arXiv:0803.4424},
year = {2008}
}