  Andreev interferometry - the sensitivity of the tunneling current to spatial
variations in the local superconducting order at an interface - is proposed as
a probe of the spatial structure of the phase correlations in the pseudogap
state of the cuprate superconductors. To demonstrate this idea theoretically, a
simple tunneling model is considered, via which the tunneling current is
related to the equilibrium phase-phase correlator in the pseudogap state. These
considerations suggest that measurement of the low-voltage conductance through
mesoscopic contacts of varying areas provides a scheme for accessing
phase-phase correlation information. For illustrative purposes, quantitative
predictions are made for a model of the pseudogap state in which the phase (but
not the amplitude) of the superconducting order varies randomly, and does so
with correlations consistent with certain proposed pictures of the pseudogap
state.
