Аннотация:It
is
found
that
spontaneous
two-photon
emission
generated
by
parametric
downconversion
should
experience
a
distinctive
type
of
diffraction,
which
can
be
observed
by
the
photon correlation method.
It
is
convenient
to interpret
the
effect
in
terms
of
advanced
waves.
Two-photon analogs
of
other
optical phenomena
are
also considered:
holography,
two-dimensional
Fourier transforms,
and
image
formation.