"Did You Know That" columnist Curt Eriksmoen begins the story of T. Keith Glennan, who was born in Enderlin, N.D., and played a role in the early days of "talking" motion pictures.
Photodetection spanning the short-, mid-, and long-wave infrared (SWIR-LWIR) underpins modern science and technology. Devices using state-of-the-art narrow bandgap semiconductors require complex manufacturing, high costs, and cooling requirements that remain prohibitive for many applications. We report high-performance infrared photodetection from a donor-acceptor conjugated polymer with broadband SWIR-LWIR operation. Electronic correlations within the π-conjugated backbone promote a high-spin ground state, narrow bandgap, long-wavelength absorption, and intrinsic electrical conductivity. These previously unobserved attributes enabled the fabrication of a thin-film photoconductive detector from solution, which demonstrates specific detectivities greater than 2.10 × 109 Jones. These room temperature detectivities closely approach those of cooled epitaxial devices. This work provides a fundamentally new platform for broadly applicable, low-cost, ambient temperature infrared optoelectro
Researchers have developed a blueprint for designing new materials using difficult combinations of nanocrystals.
The work could lead to improvements in nanocrystals already used in displays, medical imaging, and diagnostics, and enable new materials with previously impossible properties.
Researchers can make materials with new and interesting properties by bringing together nanocrystals of different compositions, sizes, and shapes. The challenge is doing that in an organized way. Now, the team has developed a strategy that explores the available nanoparticles and figures out how to stick them together.
“It’s one of those problems where ‘like likes like, ” says recent PhD graduate Katherine Elbert, who led this study while working in the lab of Chris Murray, professor in materials science and engineering at the University of Pennsylvania.