Publications by authors named "Ali Basiri"

Polarimetric imaging has a wide range of applications for uncovering features invisible to human eyes and conventional imaging sensors. Chip-integrated, fast, cost-effective, and accurate full-Stokes polarimetric imaging sensors are highly desirable in many applications, which, however, remain elusive due to fundamental material limitations. Here we present a chip-integrated Metasurface-based Full-Stokes Polarimetric Imaging sensor (MetaPolarIm) realized by integrating an ultrathin (~600 nm) metasurface polarization filter array (MPFA) onto a visible imaging sensor with CMOS compatible fabrication processes.

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Exploring emerging materials with enhanced optical nonlinearities at low power levels with ultrafast response and small footprints is of great interest for information processing, communication, sensing, and quantum systems. Recent progress on nonlinear metamaterials and metasurfaces suggests promising solutions to overcome the limitations of nonlinear materials in nature. Here we present a design concept for highly enhanced saturable absorption effect based on subwavelength-thick (<1/5λ) hybrid graphene-plasmonic metasurface structures in infrared wavelengths.

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Graphene is an attractive material for all-optical modulation because of its ultrafast optical response and broad spectral coverage. However, all-optical graphene modulators reported so far require high pump fluence due to the ultrashort photo-carrier lifetime and limited absorption in graphene. We present modulator designs based on graphene-metal hybrid plasmonic metasurfaces with highly enhanced light-graphene interaction in the nanoscale hot spots at pump and probe (signal) wavelengths.

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The manipulation and characterization of light polarization states are essential for many applications in quantum communication and computing, spectroscopy, bioinspired navigation, and imaging. Chiral metamaterials and metasurfaces facilitate ultracompact devices for circularly polarized light generation, manipulation, and detection. Herein, we report bioinspired chiral metasurfaces with both strong chiral optical effects and low insertion loss.

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Familial Adenomatous Polyposis (FAP) is an autosomal dominant disease characterized by the development of multiple colonic polyps at younger age with a near 100% lifetime risk of colorectal cancer. The determination of FAP is made after extensive clinical evaluation and genetic testing of at risk individuals. We investigated a novel spectro-polarimetric imaging system capable of capturing high-resolution images of the oral mucosa at different wavelengths in an attempt to distinguish patients with FAP from controls.

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Familial adenomatous polyposis (FAP) is an autosomal dominant disease with hundreds of colorectal adenomas in teenagers and progression to colorectal cancer if colectomy is not performed. We investigated the association of two phenotypic manifestations-oral mucosal vascular density (OMVD) and oral mucosal reflectance (OMR)--with FAP and patients with multiple colorectal adenomas. Thirty-three patients with FAP from 29 unrelated pedigrees with APC gene mutation, 5 with multiple adenomas and no known gene mutations, and 50 population controls were evaluated for the two different manifestations utilizing a photographic/spectrophotometric system capturing images and reflectance at various wavelengths.

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A 20-year-old man with persistent fifth aortic arch associated with coarctation of the aorta underwent catheterization and stenting of coarctation of the aorta.

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Skin breakdown is a prevalent and costly medical condition worldwide, with the etiologic and healing processes being complex and multifactorial. Quantitative assessment of wound healing is challenging due to the subjective measurement of wound size and related characteristics. We propose that in vivo spectral reflectance measurements can serve as valuable clinical monitoring tool/device in the study of wound healing.

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