Possibility of magnetic-field-induced reconstruction of the Fermi surface in underdoped cuprates: Constraints from infrared magneto-optics

We present an analysis of infrared optical and magneto-optical conductivity data for a range of underdoped cuprate superconductors including YBa₂Cu₃O_y and La_2−xSr_xCuO₄. In light of recent magneto-oscillation experiments which have been interpreted in terms of Fermi surface reconstruction in magnetic field, we search for far-infrared signatures of field-induced pockets of coherent quasiparticles. Analysis of the conductivity spectra in magnetic field reveals no sign of field-induced Drude-like response, as well as no evidence for modification of the pseudogap. By considering changes of the low-frequency spectral weight, we are able to place limits on the oscillator strength of coherent modes deriving from proposed field-induced pockets in the Fermi surface. In underdoped La_2−xSr_xCuO₄ we observe a complete suppression of the superfluid density but no evidence for a coherent contribution to the conductivity. Other limits are established for YBa₂Cu₃O_y. We further discuss these results in the context of cuprate systems in which stripe order can account for the observed nodal effects but does not lead to the development of antinodal pockets with long-lived quasiparticles. ©2010 The American Physical Society