Integrated InP Mach-Zehnder analog modulator

We demonstrate the use of an area selective zinc indiffusion technique to fabricate an integrated InP Mach-Zehnder optical modulator. The modulator exhibits an extinction ratio of 19 dB and a voltage swing of +/- 2.3 volts at a wavelength of 1550 nm. The extinction ratio is only reduced to -18 dB when operated over a 40 mn range, with the center wavelength around 1560 nm. The V. voltage is increased from 4 volts at 1540 nm to 7.1 volts at 1580 nm. Very good electrical isolation is obtained between the contacts, which confirms the potential of the technique for the fabrication of Photonic Integrated Circuits (PIC).