0.3 V drive voltage GaAs∕AlGaAs substrate removed Mach–Zehnder intensity modulators

Abstract

Push-pull driven Mach-Zehnder intensity modulators with a record low drive voltage of 0.3 V were realized in substrate removed very compact GaAs/ AlGaAs optical waveguides at 1.55 m. The modulator electrode is 7 mm long, corresponding to a drive voltage length product of 0.21 V cm. The modulation is due to linear electro-optic and carrier depletion effects and has a high speed potential. The propagation loss was 8 dB/ cm, making moderately long devices possible.

Ultralow Drive Voltage Substrate Removed GaAs/AlGaAs Electro-Optic Modulators at 1550 nm

“…This corresponds to 0.21 V·cm modulation efficiency, which is a world record for compound semiconductor bulk electro-optic modulators [8]. These modulators use highly confined substrate removed GaAs/AlGaAs optical guides with buried doped QW electrodes.…”

“…But differential loss between the arms due to carrier depletion can limit the ER. In the presence of this limitation, ER can be found using (8) as…”

“…This provides very high index contrast and modulator electrode gap can be made submicron. Studies in this direction have already resulted in Mach-Zehnder intensity modulators with 0.3 V V π with only 7-mm-long electrode [8]. This paper describes a detailed description of such modulators and the issues that need to be addressed to realize them successfully.…”

Ultra-low voltage GaAs/AlGaAs Mach-Zehnder intensity modulators

“…High speed operation of such modulators up to 35 GHz with drive voltage of 5 V was also demonstrated [3]. In this paper we present a novel approach that yields record low drive voltage of 0.3 V in a Mach-Zehnder intensity modulator [4].…”

Traveling Wave Electrodes for Substrate Removed Electro-Optic Modulators With Buried Doped Semiconductor Electrodes

“…Result is very strong modulating field overlapping very well with the optical mode and significant drive voltage reduction. Using this approach in our previous work, we demonstrated 0.3 V V π Mach Zehnder Modulators (MZMs) in bulk GaAs [4] and 0.8 V V π in InP using multi quantum well cores [5]. However, wide bandwidth operation of such devices has not been demonstrated yet.…”