Highly-Linear Integrated Modulators

​Linear optical modulators are key devices for RF photonics systems, particularly RF Photonic Links, and also to generate complex modulation formats in high speed digital systems.  At Morton Photonics (MP), high linearity analog systems are being developed through a combinaton of silicon photonics modulators and MPs ULN lasers, with one goal of fabricating integrated Transmit and Receive PICs using heterogeneous integration on the Silicon Photonics platform.  MP has demonstrated record linearity for silicon photonics modulators, using III-V materials for the phase modulation sections of a Mach-Zehnder interferometer (MZI) modulator, showing performance similar to often used (but high SWaP-C) Lithium Niobate MZI modulators.  Linearized MZI modulators developed by MP, using highly coupled ring phase modulation sections, have produced even higher linearity performance.

MP developed novel, highly linear, miniature, silicon modulators to provide the required optical modulation for high SFDR analog links, and to be used in advanced PIC devices as part of a phased array sensor system.  Record results for spurious free dynamic range (SFDR) in all-silicon photonics devices were obtained in initial prototype devices. Further work using heterogeneously integrated III-V/Si phase modulation sections within MZI modulators produced significantly improved performance, similar to Lithium Niobate modulators, with an SFDR of 112dB.Hz2/3 at 10 GHz.  Further improved SFDR results were demonstrated using Ring Assisted MZI (RAMZI) linearized modulators, utilizing heterogeneously integrated III-V/Si phase modulation sections, which provided a record SFDR value of 117 dB.Hz2/3 at 10GHz.​​  The same program included the invention of a new, single port optical modulator, the Grating Assisted Michelson Interferometer (GAMI) modulator.