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J. Edgar

Publications and source records attributed to J. Edgar.

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Response of wavelength-shifting and scintillating-wavelength-shifting fibers to ionizing radiation

We report results of characterizing the response and light transport of wavelength-shifting (WLS) and scintillating-wavelength-shifting (Sci-WLS) fibers under irradiation by radioactive $\alpha$, $\beta$, and $\gamma$ sources. Light yield and light transmission were measured for the WLS fiber BCF-91A from Saint-Gobain and for a new Sci-WLS fiber EJ-160 from Eljen Technology. The two variants with different fluor mixtures, EJ-160I and EJ-160II, exhibited approximately five and seven times higher light yield than BCF-91A, respectively, while their attenuation lengths were 3.80\,m for BCF-91A, 4.00\,m for EJ-160I, and 2.50\,m for EJ-160II.

physics.ins-det

Optical characterization of wavelength-shifting and scintillating-wavelength-shifting fibers

We report results of optical characterizations of new wavelength-shifting and scintillating-wavelength-shifting fibers EJ-182 and EJ-160 from Eljen Technology and compare them to the wavelength-shifting fiber BCF-91A from Saint-Gobain. The wavelength-dependence of attenuation was derived from spectral measurements confirming that the long attenuation length increases with wavelength, while short attenuation effects become less significant at longer wavelengths. The impact of the environmental refractive index was studied by immersing the EJ-160II fiber in water. Immersing the fiber in water reduced the overall light output and suppressed the short attenuation component, which can be explained by reduced light-collection efficiency due to the smaller refractive-index contrast between the fiber cladding and the surrounding medium.

physics.ins-det

Enhanced Light-Matter Interaction in B-10 Monoisotopic Boron Nitride Infrared Nanoresonators

Phonon-polaritons, mixed excitations of light coupled to lattice vibrations (phonons), are emerging as a powerful platform for nanophotonic applications. This is because of their ability to concentrate light into extreme sub-wavelength scales and because of their longer phonon lifetimes than their plasmonic counterparts. In this work, the infrared properties of phonon-polaritonic nanoresonators made of monoisotopic B-10 hexagonal-boron nitride (h-BN) are explored, a material with increased phonon-polariton lifetimes compared to naturally abundant h-BN due to reduced photon scattering from randomly distributed isotopes. An average relative improvement of 50% in the nanoresonators Q factor is obtained with respect of nanoresonators made of naturally abundant h-BN. Moreover, the monoisotopic h-BN nano-ribbon arrays are used to sense nanometric-thick films of molecules, both through surface-enhanced absorption spectroscopy and refractive index sensing. In addition, strong coupling is achieved between a molecular vibration and the phonon-polariton resonance in monoisotopic h-BN ribbons.

physics.optics