Low Voltage, High Optical Power Handling Capable, Bulk Compound Semiconductor Electro-Optic Modulators at 1550 nm

AlGaAs bulk electro-optic Mach-Zehnder modulators with low Vp are reported. Epilayer design is an npin, which is shown to be equivalent to a pin. Measured Vp is 1 V for 1 cm long electrode and this result agrees very well with the numerical modeling. Modulator capacitance remains constant and current through the device is negligible over a wide bias range. Lowest bandgap of the material in the active waveguide region is larger than twice the photon energy at 1550 nm, significantly reducing material absorption, including two-photon absorption. Modulator characteristics remain unchanged under coupled input optical powers approaching 160mW. Low Vp combined with high optical power handling capability make these devices suitable for analog photonic links.