Wavelength-independent optical two-tone signal generator composed of one single Mach-Zehnder optical modulator and a polarizer

We demonstrate generation of 60-GHz-separation optical two-tone signal at arbitrary C-band wavelength, utilizing selective suppression of undesired low-order optical sidebands by a polarizer. Without involving complicated optical wavelength filtering, more than 20-dB suppression of undesired ±1st-order ones has been successfully achieved over 40-nm wavelength range.