Accession Number:

ADA416362

Title:

Dynamically Tunable Photonic Bandgap Crystal Components

Descriptive Note:

Final rept. 15 Aug 2002-14 Feb 2003

Corporate Author:

TESLA TECHNOLOGIES INC KNOXVILLE TN

Report Date:

2003-02-01

Pagination or Media Count:

11.0

Abstract:

Periodic photonic crystal structures channel electromagnetic waves much as semiconductorsquantum wells channel electrons. Photonic bandgap crystals PBC are fabricated by arranging sub-wavelength alternating materials with high and low dielectric constants to produce a desired effective bandgap. Photons with energy within this bandgap cannot propagate through the structure. This property has made these structures useful for microwave applications such as frequency-selective surfaces, narrowband filters, and antenna substrates when the dimensions are on the order of millimeters. They are also potentially very useful, albeit much more difficult to fabricate, in the visiblenear-infrared region for various applications when the smallest dimensions are at the edge of current microlithography fabrication tools. We micro-fabricated suspended free standing micro-structure bridge waveguides to serve as substrates for PBC features. These micro-bridges were fabricated onto commercial silicon-on-insulator SOI wafers. Nanoscale periodic features were fabricated onto these micro-structure bridges to form a tunable system. When this combined structure is perturbed, such as mechanical deflection of the suspended composite structure at resonance, there can be a realtime shift in the material effective bandgap due to slight geometric alterations due to the induced mechanical stress. Extremely high resonance frequenciesdevice speeds are possible with these very small dimension MEMS.

Subject Categories:

  • Electrooptical and Optoelectronic Devices
  • Crystallography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE