Multi-pathway all-optical wavelength conversion switching and routing via four- and six-wave mixing in hot rubidium vapour

We report an experimental demonstration of multi-pathway all-optical switching and routing via efficient wavelength conversion in hot rubidium vapour. We apply a coupling field and a control field to drive both 87Rb and 85Rb isotope atoms into either the double-Λ or triple-Λ configuration when a probe field is scanned across the D1 line of the rubidium atom. We find that this driving scheme facilitates the coherent generation of seven wave-mixing signals with different frequencies and polarizations based on four-wave mixing and six-wave mixing interactions. Also, each generated signal can be switched on and off simply by modulating the control field in frequency to optimize or suppress one specific wave-mixing interaction.