Ultralinear heterogeneously integrated ring-assisted Mach–Zehnder interferometer modulator on silicon

Abstract

A linear modulator is indispensable for radio frequency photonics or analog photonic link applications where high dynamic range is required. There is also great interest to integrate the modulator with other photonic components, to create a photonic integrated circuit for these applications, with particular focus on silicon photonics integration in order to take advantage of complementary metal-oxide-semiconductor compatible foundries for high-volume, low-cost devices. However, all silicon modulators, including the highest performing Mach-Zehnder interferometer (MZI) type, have poor linearity, partially due to the inherent nonlinearity of the MZI transfer characteristic, but mostly due to the nonlinearity of silicon's electro-optic phase shift response. In this work, we demonstrate ultralinear ring-assisted MZI (RAMZI) modulators, incorporating heterogeneously integrated III-V multiple quantum wells on silicon phase modulation sections to eliminate the nonlinear silicon phase modulation response. The heterogeneously integrated III-V/Si RAMZI modulators achieve record-high spurious free dynamic range (SFDR) for silicon-based modulators, as high as 117.5 dB • Hz 2∕3 at 10 GHz for a weakly coupled ring design, and 117 dB • Hz 2∕3 for a strongly coupled ring design with higher output power. This is a higher SFDR than typically obtained with commercial lithium niobate modulators. This approach advances integrated modulator designs on silicon for applications in compact and high-performance analog optical systems.

High-power sub-kHz linewidth lasers fully integrated on silicon

“…The 500 nm thick silicon can achieve index matching between the silicon waveguide and the III-V epitaxial stack to provide a suitable Si/III-V hybrid mode in the gain section [34][35][36]. The use of a thick (500 nm) silicon layer has also been demonstrated to support high linearity heterogeneous silicon/III-V modulators [37] with high operating power [38], and high bandwidth photodetectors [9].…”

Nanophotonic lithium niobate electro-optic modulators

“…As a result, they remain bulky (∼ 10 cm long), discrete, expensive, and require highpower electrical drivers [1,2]. Integrated silicon (Si) [4][5][6][7] and indium phosphide (InP) [8][9][10] photonics are promising solutions for scalability but come at the cost of compromised performance [4][5][6][7][8][9][10]. Here we demonstrate monolithically integrated LN electro-optic modulators that are orders of magnitudes smaller and more efficient than traditional bulk LN devices while preserving LN's excellent material properties.…”

High-Power, High-Linearity, Heterogeneously Integrated III-V on Si MZI Modulators for RF Photonics Systems

“…This paper addresses high optical power operation of the heterogeneously integrated III-V/SI MZI modulators through extensive device testing using a high power (1 Watt), polarization maintaining (PM) erbium doped fiber amplifier (EDFA). Additional previous work by the authors demonstrated III-V/Si RAMZI modulators with demonstrated SFDR at 10 GHz as high as 117 dB.Hz 2/3 [25], and suggested a further improvement in device linearization, using a novel Grating Assisted Michelson interferometer (GAMI) modulator [26].…”