Engineering topics

Stewart, Kenneth

Publications and source records attributed to Stewart, Kenneth.

4 records

DOE OSTI2025

The neurobench framework for benchmarking neuromorphic computing algorithms and systems

Neuromorphic computing shows promise for advancing computing efficiency and capabilities of AI applications using brain-inspired principles. However, the neuromorphic research field currently lacks standardized benchmarks, making it difficult to accurately measure technological advancements, compare performance with conventional methods, and identify promising future research directions. This article presents NeuroBench, a benchmark framework for neuromorphic algorithms and systems, which is collaboratively designed from an open community of researchers across industry and academia. NeuroBench introduces a common set of tools and systematic methodology for inclusive benchmark measurement, delivering an objective reference framework for quantifying neuromorphic approaches in both hardware-independent and hardware-dependent settings. For latest project updates, visit the project website (neurobench.ai).

Yik, Jason [Harvard Univ., Cambridge, MA (United S↗

NASA NTRS1999

Broadband Infrared Antireflection Structured Silicon Surfaces

Silicon and germanium are materials often used for IR windows and optical elements. However they have a very high index of refraction, in the order of three to four, which causes large reflection losses on each surface. These losses are especially high under large angles of incidence which are often desirable if signals are faint and fast optics are to be used. Solid antireflection coatings are either not available because materials with appropriate index of refraction do not exist, or their use is limited to a small wavelength range and small angles of incidence. We will present the status of our work to calculate, create, and test the performance of graded structures in Si to reduce its surface reflection. The structures are expected to work over the very broad wavelength range of 10 to 1000 micrometers and a wide range of angle of incidence. We have identified several high aspect ratio MEMS process techniques to Create the structures and have done 3D electromagnetic modeling, which predicts significant effects. Measurements on different samples have validated our modeling.

Stewart, Kenneth↗

NASA NTRS1999

Broadband Infrared Antireflection Structured Silicon Surfaces

Silicon and germanium are materials often used for infrared (IR) windows and optical elements. However they have a very high index of refraction, in the order of three to four, which causes large reflection losses on each surface. These losses are especially high under large angles of incidence which are often desirable if signals are faint and fast optics are to be used. Solid antireflection coatings are either not available because materials with appropriate index of refraction do not exist, or their use is limited to a small wavelength range and small angles of incidence. We will present the status of our work to calculate, create, and test the performance of graded structures in Si to reduce its surface reflection. The structures are expected to work over the very broad wavelength range of 10 micron to 1000 micron and a wide range of angle of incidence. We.have identified several high aspect ratio MEMS process techniques to create the structures and have done 3D electromagnetic modeling, which predicts significant effects. Measurements on different samples have validated our modeling.

Stewart, Kenneth↗

NASA NTRS1998

Broadband Infrared Antireflection Structured Silicon Surfaces

Silicon and germanium are materials often used for IR windows and optical elements. However they have a very high index of refraction, in the order of three to four, which causes large reflection losses on each surface. These losses are especially high under large angles of incidence which are often desirable if signals are faint and fast optics are to be used. Solid antireflection coatings are either not available because materials with appropriate index of refraction do not exist, or their use is limited to a small wavelength range and small angles of incidence. We will present the status of our work to calculate, create, and test the performance of graded structures in Si to reduce its surface reflection. The structures are expected to work over the very broad wavelength range of 10 microns to 1000 microns and a wide range of angle of incidence. We have identified several high aspect ratio MEMS process techniques to create the structures and have done 3D electromagnetic modeling, which predicts significant effects. Measurements on different samples have validated our modeling.

Stewart, Kenneth↗