Design and characterization of a low optical loss depletion mode silicon optical modulator

Abstract

In this paper, a new design of a depletion mode silicon optical modulator is proposed which has low optical loss of 1.31 dB/mm at reverse bias voltage of 8 V. The modulator consists of two Schottky contacts which provide two extra depletion region in the phase shifter. The low optical loss results in better performance of the device which makes the 40 Gbit/s modulation bandwidth possible. Moreover, the phase shift efficiency of the device is achieved as 2.8 V·cm. The optical eye diagram of the new device shows 6.5 dB extinction ratio and decision point of 21.8 ps is produced for the 3.5 mm long Mach-Zehnder modulator.