  We investigate the statistical properties of wavefunctions in an open chaotic
cavity. When the number of channels in the openings of the billiard is
increased by varying the frequency, wavefunctions cross over from real to
complex. The distribution of the phase rigidity, which characterizes the degree
to which a wavefunction is complex, and long-range correlations of intensity
and current density are studied as a function of the number of channels in the
openings. All measured quantities are in perfect agreement with theoretical
predictions.
