A Versatile Bias Control Technique for Any-Point Locking in Lithium Niobate Mach–Zehnder Modulators

A versatile bias control technique for lithium niobate Mach-Zehnder modulators was demonstrated. Using this technique, bias locking at any arbitrary position along the transfer function was achieved with better than ±0.1° accuracy. This technique was shown to be independent of optical input power to the modulator. In addition, this bias control technique was also proven to be robust and simple to implement in field applications.