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Burckel, David Bruce

Publications and source records attributed to Burckel, David Bruce.

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Zero-Power Analog Optical Processing

The motivation behind this research is the growing challenge of handling the massive amounts of data generated by modern imaging systems. Conventional digital image processing techniques are struggling to keep pace with the demands of high-resolution and high-speed imaging systems for remote sensing due to their high-power consumption and data storage requirements. We present a novel approach based on analog photonics to address this challenge. The proposed system utilizes a silicon-photonics-based image encoder positioned after image formation and initial optical-to-electrical conversion. The photonic encoder compresses image data using a passive disordered photonic structure to perform kernel-type random projections of the raw data. The compressed data is then processed by a back-end neural network, which reconstructs the original image with high fidelity (structural similarity exceeding 90%). Our proposed approach has the potential to compress images with ~ 1000X lower power consumption compared to digital approaches with data rates exceeding 1 terapixel/second.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2021

Optical devices enabled by vertical dielectric Mie resonators

Dielectric resonators provide a building block for the development of low-loss resonant metamaterials because they replace lossy ohmic currents of metallic resonators with low-loss displacement currents. The spectral locations of electric and magnetic dipole resonances of a dielectric resonator can be tuned by varying the resonator geometry so that desired scattering properties are achieved.

Campione, Salvatore↗
DOE OSTI2020

Kinematic chip to chip bonding

The various technologies presented herein relate to integrating an IC having at least one waveguide incorporated therein with a v-groove array IC such that an optical fiber located in a v-groove is aligned relative to a waveguide in the IC maximizing optical coupling between the fiber and the waveguide. The waveguide IC and the v-groove array IC are bonded in a stacked configuration. Alignment of the waveguide IC and the array IC in the stacked configuration enables advantage to be taken of lithographic accuracy of features formed with respect to the Z-direction. Further, kinematic pins and sockets are utilized to provision accuracy in the X- and Z-directions, wherein advantage is taken of the placement accuracy and fabrication tolerance(s) which can be utilized when forming the and sockets. Accordingly, automated alignment of the waveguide IC and the array IC is enabled, facilitating accurate alignment of the respective waveguides and fibers.

42 ENGINEERING↗
DOE OSTI2020

Fabrication of multilayered carbon MEMS devices

The various technologies presented herein relate to formation of carbon micromechanical systems (CMEMS), wherein the CMEMS comprise multiple layers of carbon structures and are formed using a plurality of photoresist precursors that are processed to form carbon. The various embodiments can be utilized in producing a plurality of CMEMS with full production level fabrication, e.g., 6 inch wafers can be processed. A pyrolyzed layer of carbon is lithographically defined after pyrolysis, wherein the post-pyrolysis etch process can produce carbon structures having repeatable and accurate device geometries, with straight sidewalls. A sacrificial layer can be applied to facilitate separation of a first carbon layer from a second carbon layer, wherein, upon pyrolysis to form the second carbon layer and lithography thereof, the sacrificial layer is removed to form a CMEMS comprising a first carbon layer (e.g., comprising bottom contacts) located beneath a second carbon layer (e.g., a mechanical layer).

36 MATERIALS SCIENCE↗
DOE OSTI2019

Rapidly tunable, narrow-band infrared filter arrays

Tunable filters can use Fano metasurface designs having extremely narrow transmission bands. The Fano metasurface can comprise dielectric or semiconductor materials and can produce transmission bands with quality factors well in excess of 1000—at least a factor of 50 greater than typical metamaterial-based infrared resonances. Numerical simulations of these metasurfaces show that the spectral position of the passband can be changed by slightly changing the position of a small dielectric perturbation block placed within the near-field of the resonator by using simple electromechanical actuation architectures that allow for such motion. An array of independently tunable narrowband infrared filters can thereby be fabricated that only requires deep-subwavelength motions of perturbing objects in the resonator's near-field.

Sinclair, Michael B.↗
DOE OSTI2019

Enhancing Absorption Bandwidth through Vertically Oriented Metamaterials

Metamaterials research has developed perfect absorbers from microwave to optical frequencies, mainly featuring planar metamaterials, also referred to as metasurfaces. In this study, we investigated vertically oriented metamaterials, which make use of the entire three-dimensional space, as a new avenue to widen the spectral absorption band in the infrared regime between 20 and 40 THz. Vertically oriented metamaterials, such as those simulated in this work, can be experimentally realized through membrane projection lithography, which allows a single unit cell to be decorated with multiple resonators by exploiting the vertical dimension. In particular, we analyzed the cases of a unit cell containing a single vertical split-ring resonator (VSRR), a single planar split-ring resonator (PSRR), and both a VSRR and PSRR to explore intra-cell coupling between resonators. We show that the additional degrees of freedom enabled by placing multiple resonators in a unit cell lead to novel ways of achieving omnidirectional super absorption. Our results provide an innovative approach for controlling and designing engineered nanostructures.

36 MATERIALS SCIENCE↗