Scalable wavelength-converting crossbar switches

We report scalable low-power wavelength-converting crossbar switches that monolithically integrate two-dimensional compact arrays of surface-normal photodiodes with quantum-well waveguide modulators. We demonstrate proof-of-concept, electrically reconfigurable 2×2 crossbars that perform unconstrained wavelength conversion across 35 nm in the C-band (1530-1565 nm), using only <4.3-mW absorbed input optical power, and with 10-dB extinction ratio at 1.25 Gb/s. Such wavelength-converting crossbars provide complete flexibility to selectively convert any of the input wavelengths to any of the output wavelengths at high data bit rates in telecommunication, with the input and output wavelengths being arbitrarily chosen within the C-band.