  The normal-state behavior of the temperature-dependent Hall coefficient in
cuprate superconductors is investigated using linear response theory. The Hall
conductivity is of paramount importance in that its sign and magnitude directly
reflect the sign of the charge carriers and the size of particle-hole asymmetry
effects. Here we apply a strong-pairing fluctuation theory that incorporates
pseudogap effects known to be important in cuprate transport. As a result, in
the vicinity of the transition temperature our theoretical approach goes beyond
the conventional superconducting fluctuation formalism. In this regime,
pseudogap effects are evident in both the transverse and longitudinal
conductivities and the bosonic response is explicitly gauge invariant. The
presence of a gap in the excitation spectrum is also apparent at higher
temperatures, where the gapped fermionic quasiparticles are the dominant
contribution to the Hall coefficient. The observed non-monotonic temperature
dependence of the Hall coefficient therefore results from a delicate interplay
between the fermionic quasiparticles and the bosonic fluctuations. An important
feature of our work is that the sign of the Hall conductivity from the Cooper
pair fluctuations is the same as that of their fermionic constituents. Thus, we
find no sign change in the Hall coefficient above the transition temperature.
This prediction is corroborated by experiments, away from special charge
ordering stoichiometries. The theoretical results presented in this paper
provide crucial signatures that can be experimentally verified, enabling
validation of the present theory.
