Tunable graphene-based infrared reflectance filter having patterned nanoantenna layer and unpatterned graphene layer

Patent · Mon Dec 28 23:00:00 EST 2020

OSTI ID:1771771

Beechem, III, Thomas Edwin; Goldflam, Michael; Howell, Stephen W.; Peters, David W.; Ruiz, Isaac; Davids, Paul

An actively tunable optical filter can control the amplitude of reflected infrared light. The filter exploits the dependence of the excitation energy of plasmons in a continuous and unpatterned sheet of graphene, on the Fermi-level, which can be controlled by conventional electrostatic gating. An exemplary filter enables simultaneous modification of two distinct spectral bands whose positions are dictated by the device geometry and graphene plasmon dispersion. Within these bands, the reflected amplitude can be varied by over 15% and resonance positions can be shifted by over 90 cm−1. Electromagnetic simulations verify that tuning arises through coupling of incident light to graphene plasmons by a nanoantenna grating structure. Importantly, the tunable range is determined by a combination of graphene properties, device structure, and the surrounding dielectrics, which dictate the plasmon dispersion. Thus, the underlying design is applicable across a broad range of infrared frequencies.

• Research Organization: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: NA0003525
• Assignee: National Technology & Engineering Solutions of Sandia, LLC (Albuquerque, NM)
• Patent Number(s): 10,877,194
• Application Number: 15/872,293
• OSTI ID: 1771771
• Country of Publication: United States
• Language: English