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We demonstrate efficient photonic devices that rely on sub-100nm features in unmodified 45nm SOI CMOS, including photonic crystals, array-antenna grating couplers, and modulators. We then show monolithically integrated electronic-photonic systems comprising millions of transistors and thousands of photonic devices, including a complete chip-to-chip photonic link.

United States. Defense Advanced Research Projects Agency. Photonically Optimized Embedded Microprocessors Program (Award HR0011-11-C-0100)

A finite-difference, complex-wavevector photonic band structure solver with perfectly matched layer absorbing boundaries is presented. Modal properties of leaky-wave structures, such as silicon photonic grating couplers and waveguide crossing arrays, are shown.

A two-dimensional finite-difference complex wavevector band structure solver for nanophotonics applications is presented, and rigorous computation of modal properties within bandgaps of periodic devices, including mirror strength, is shown.

Numerically rigorous full-wave electromagnetic analysis of scattering from hailstones based primarily on the method of moments is presented. The analysis employs generalized curved hexahedral volume and surface elements of arbitrary geometrical-mapping orders, current polynomial vector basis functions of arbitrarily high expansion orders, and higher order modeling of inhomogeneous lossy dielectric materials. The method can accurately and efficiently model and analyze scattering from dry, wet, and melting hailstones of various realistic shapes and material compositions, including layered models and continuous variations of the dielectric permittivity.

Analysis of electromagnetic scattering from hailstones has conventionally been done using the T-matrix method. This method, which reduces exactly to the Lorenz-Mie scattering theory when the scattering particle is a homogeneous or layered piecewise homogeneous sphere, worked well so far when we tried to understand the measurements. However the measurements have become fairly sophisticated with many decades of multiple polarization measurements and the current models are not able to explain many of the nuances in the measurements, because the current model is not well suited for analysis of arbitrarily shaped and non-layered particles.

We demonstrate a finite-difference approach to complex-wavevector band structure simulation and its use as a tool for the analysis and design of periodic leaky-wave photonic devices. With the (usually real) operating frequency and unit-cell refractive index distribution as inputs, the eigenvalue problem yields the complex-wavevector eigenvalues and Bloch modes of the simulated structure. In a two-dimensional implementation for transverse-electric fields with radiation accounted for by perfectly matched layer boundaries, we validate the method and demonstrate its use in simulating the complex-wavevector band structures and modal properties of a silicon photonic crystal waveguide, an array-antenna-inspired grating coupler with unidirectional radiation, and a recently demonstrated low-loss Bloch-mode-based waveguide crossing array. Additionally, we show the first direct solution of the recently proposed open-system low-loss Bloch modes. We expect this method to be a valuable tool in photonics design, enabling the rigorous analysis and synthesis of advanced periodic and quasi-periodic photonic devices.