Methods for measuring the RF half-wave voltage of LiNbO3 optical modulators

Abstract

We present methods to measure the RF half-wave voltage Vπ(f) using a photodetector and an RF spectrum analyzer based on (i) the nonlinear response and (ii) the two-point technique. The results obtained from these methods for an LiNbO3 Mach–Zehnder optical modulator at 6.3 GHz are compared and good agreement is found between all the methods. Also, measurement methods based on optical-spectrum techniques, namely, the optical response and two-tone methods, are analyzed. An error analysis shows that the new and simpler techniques proposed offer similar levels of measurement uncertainty. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 440–443, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21011