  We demonstrate an unseeded, multimode four-wave mixing process in hot
$^{85}$Rb vapor, using two pump beams of the same frequency that cross at a
small angle. This results in the simultaneous fulfillment of multiple
phase-matching conditions that reinforce one another to produce four
intensity-stabilized bright output modes at two different frequencies. Each
generated photon is directly correlated to exactly two others, resulting in the
preferred four-mode output, in contrast to other multimode four-wave mixing
experiments. This provides significant insight into the optimal configuration
of the output multimode squeezed and entangled states generated in such
four-wave mixing systems. We examine the power, temperature and frequency
dependence of this new output and compare to the conical four-wave mixing
emission from a single pump beam. The generated beams are spatially separated,
allowing a natural distribution for potential use in quantum communication and
secret-sharing protocols.
