From Displays to Datacom: Unleashing the Pockels Effect in Silicon via Ferroelectric Nematic Liquid Crystals

With data-intensive applications driving demand for higher bandwidth and lower power consumption, silicon photonics is established as the premier platform for optical interconnects. However, native silicon’s lack of a strong second-order nonlinear optical X (2) effect has historically forced reliance on free-carrier dispersion for optical modulation. This mechanism limits the scalability of next-generation transceivers, inherently introducing performance trade-offs between footprint, insertion loss, bandwidth, and power consumption.

This presentation explores a novel hybrid integration approach that leverages a new material platform to overcome the limitations of standard silicon (photonics) modulators. Ferroelectric nematic liquid crystals (FNLCs) exhibit massive second-order nonlinear optical X(2) coefficients (and spontaneous polar ordering) qualities that bridge a critical materials gap and unlock the ultra-fast, electro-optic Pockels effect within a highly processable fluid medium. This capability was previously reserved for rigid solid-state crystals.

Indeed, the use of FNLCs addresses a well-known limitation in liquid crystals (LCs). LCs are foundational to optics technologies, though their utility has been strictly relegated to low-speed applications (displays, spatial light modulators). This limitation stems from their reliance on the slow dynamics of bulk molecular reorientation under an electric field.

In the hybrid integration approach, a slotted waveguide architecture is used to tightly confine the optical mode within a nanoscale dielectric slot. Back-end-of-line (BEOL) processing is used to fill this slot with the highly responsive FNLC material. This architecture maximizes the overlap integral between the modulating radio-frequency field and the optical field where the X(2) effect is strongest. The result is a critical pathway toward ultra-efficient, high-bandwidth optical engines.

• Additional areas of focus include:
  • Waveguide Architecture: The design and mechanics of slotted silicon waveguides optimized to harness hybrid electro-optic material properties.
  • Performance Breakthrough: How this integration inherently reduces the half-wave voltage-length product (VpL), enabling ultra-compact, high-speed modulators capable of 400G/lane data rates and beyond.
  • The LC Paradigm Shift: The underlying physics of FNLCs that are transitioning LC technology from millisecond molecular reorientation to gigahertz-scale electro-optic Pockels modulation.
  • Manufacturing Viability: The fluid nature of FNLCs and their seamless compatibility with existing CMOS and silicon photonics foundry processes via simple BEOL integration.

About the presenter
Cory Pecinovsky, Ph.D., is the co-founder and CTO at Polaris Electro-Optics, a Colorado-based company pioneering the future of optical interconnects. Pecinovsky leads the development and commercialization of Polaris’s proprietary ferroelectric nematic liquid crystal (FNLC) technology. By integrating these highly efficient, poling-free materials into silicon photonics, his team is creating ultra-high-speed, low-energy modulators designed to meet the extreme computational demands of modern AI, cloud datacenters, and high-performance computing.

After earning his doctorate in organic chemistry from the University of Colorado Boulder, Pecinovsky dedicated his industrial career to the advancement of liquid crystals and nonlinear optical materials. Following the CU-Boulder team’s landmark 2020 publication on the FNLC phase—a material that perfectly bridges those two fields—he immediately saw the disruptive potential. Recognizing that his dual expertise was uniquely suited to the challenge, he pivoted to bring this novel electro-optic technology to market.