Silicon Photonic Single-Sideband Generation with Dual-Parallel Mach-Zehnder Modulators

Abstract

We demonstrate a silicon photonic carrier-suppressed single-sideband (CS-SSB) modulator with dual-parallel Mach-Zehnder modulators (DP-MZMs) operating near 1550 nm with a measured carrier suppression of 30 dB and an ultra-high sideband suppression (SSR) of 47.8 dB at 1 GHz with peak conversion efficiency of -6.846 dB (20.7%). We extensively study the effects of imbalances in both the optical and RF phases and amplitudes on the side-band performance. Furthermore, with our silicon photonic modulator, we successfully demonstrate state-selective detection for atoms with time-multiplexed frequency shifting and atom interferometer fringes in a Rubidium ( 87 Rb) atom system to estimate gravitational acceleration. These multidisciplinary efforts demonstrate progress towards an integrated silicon photonic chip-scale laser system for atom interferometry and quantum information science applications.

Integrated Optical SSB Modulation / Frequency Shifting Using Cascaded Silicon MZM

“…(7) may be rewritten: is the modulation index. The pre-factor √2 confirms the 3-dB electrical advantage of the proposed architecture in comparison to circuits presented in [5,[8][9]. The 3-dB optical advantage is not realised because of the presence of the third stage.…”

“…A notable advance on the design of the desired function is presented in [7] and a DC bias-less and filter-less scheme based on MMI couplers has been reported [8]. A silicon-based DP-MZM architecture for 1 GHz frequency shifting is reported in [9]. All these architectures are directly equivalent to a single stage generalized Mach-Zehnder Interferometer (GMZI) circuit: an 1 × splitter directly interconnected to a × 1 combiner via an array of linear electro-optic phase modulators.…”

“…However, the original design confirms the 3-dB optical advantage as well. It can be understood from (9), that all the even harmonics are suppressed including the carrier. The principal sidebands are -1, +3, and -5.…”

“…FFICIENT single side band suppressed carrier (SSB-SC) modulation technology for frequency conversion or shifting is a growing need and fundamental to radio frequency photonic systems. Starting from the very first demonstration [1] of an integrated SSB modulator based on a Ti-diffused LiNbO3 optical waveguide circuit driven by an in-phase (I) and quadrature (Q) signal at 2 GHz, there has been a plethora of publications [2][3][4][5][6][7][8][9] describing different techniques for obtaining the desired functions. All the architectures presented in references [1][2][3][4][5][7][8][9] use circuits of Mach-Zehnder Modulators (MZM).…”

“…In this scheme, the optical carrier is modulated by the in-phase and quadrature component of the RF drive signal. However, a dualparallel Mach Zehnder Modulator (DP-MZM) is the most widely used solution because of its superior carrier and sideband suppression [3,5,[7][8][9]. In this scheme, two child MZM are biased at the minimum transmission point (MITP) while the parent MZM is kept at the quadrature bias point (QTP).…”