University of Delaware

Lumilant, Inc.

Ahmed Sharkawy

Dennis W Prather

Shouyun Shi

Mathew Zablocki

Richard A Soref

Caihua Chen

An optical routing element may include a planar dielectric photonic crystal which includes a lattice of holes having a first linear defect adjacent a second linear defect, with the two defects being separated by a central row of lattice holes. The first linear defect in the lattice of holes may form a first single mode line defect waveguide, and the second linear defect in the lattice of holes may form a second single mode line defect waveguide. Optical energy may be selectively coupled between the first and second waveguides across the central row of lattice holes. A free-carrier injector may be included to inject free-carriers into the dielectric photonic crystal, activation of which may alter selectivity of the optical coupling between the first and second waveguides. A plurality of optical routing elements with associated free-carrier injectors may be interconnected to form a bi-directional optical routing array.

Optical router having optical routing nodes of four bi-directional optical switches

Optical router using interconnected photonic crystal elements with specific lattice-hole geometry

A transfer process for silicon nanomembranes (SiNM) may involve treating a recipient substrate with a polymer structural support. After treating the recipient substrate, a substrate containing the intended transferable devices may be brought in direct contact with the aforementioned polymer layer. The two substrates may then go through a Deep Reactive Ion Etch (DRIE) to remove at least a portion of the substrate containing the devices. Oxide may be selectively removed with a buffered oxide wet etch, leaving the transferred SiNM on the recipient substrate with the Underlying polymer layer.

Transfer method for thin film nanomembrane structures

An electro-optical switch implemented in coupled photonic crystal waveguides is disclosed. The switch is proposed and analyzed using both a finite-difference time-domain ('FDTD') method and a plane wave expansion ('PWM) method. The switch may be implemented in a square lattice of silicon posts in air, as well as in a hexagonal lattice of air holes in a silicon slab. Switching occurs due to a change in the conductance in the coupling region between the photonic crystal waveguides, which modulates the coupling coefficient and eventually causes switching. Conductance may be induced electrically by carrier injection or optically by electron-hole pair generation. The electro-optical switch has low insertion loss and optical crosstalk in both the cross and bar switching states.

Electro-optical switching using coupled photonic crystal waveguides

Described herein is a multi-channel wavelength division multiplexing (WDM) device including a two-dimensional photonic crystal. The photonic crystal consists of two primary components: (1) a waveguiding element created by line defects formed in the photonic crystal, and (2) frequency-selective elements created by high Q-value microcavities formed in the crystal. The multi-channel WDM system offers a flexible design and high channel density.

Multi-channel wavelength division multiplexing using photonic crystals

A two-dimensional, hetero-structure photonic crystal includes a first rectangular lattice array of dielectric rods provided on a portion of an air background, and a second rectangular lattice array of dielectric rods provided on another portion of the air background. The two-dimensional, hetero-structure photonic crystal provides the advantages of both the rectangular and triangular lattice arrays for application with optical beam splitters and combiners, and achieves a transmission efficiency greater than 90% in comparison to the transmission efficiency of 50% for the conventional uni-structure photonic crystals.

Hetero-structure photonic bandgap materials

In an optical coupling system, an optical coupler having a dielectric mirror or Gaussian beam mirror is used to efficiently couple optical signals to photonic crystal waveguides. Dielectric mirrors offer the advantage of optical coupling between dielectric waveguides and single mode photonic crystal waveguides. Various types of optical couplers may be implemented with or without a dielectric waveguide in the system.

Growing community of inventors

Newark, DE, United States of America

Ahmed Sharkawy