Bullseye dielectric cavities for photon collection from a surface-mounted quantum-light-emitter

Coupling light from a point source to a propagating mode is an important problem in nano-photonics and is essential for many applications in quantum optics. Circular "bullseye" cavities, consisting of concentric rings of alternating refractive index, are a promising technology that can achieve near-unity coupling into a first lens. Here we design a bullseye structure suitable for enhancing the emission from dye molecules, 2D materials and nano-diamonds positioned on the surface of these cavities. A periodic design of cavity, meeting the Bragg scattering condition, achieves a Purcell factor of 22.5 and collection efficiency of 80%. We also tackle the more challenging task of designing a cavity for coupling to a low numerical aperture fibre in the near field. Finally, using an iterative procedure, we study how the collection efficiency varies with apodised (non-periodic) rings.

Postsurgical follow-up study of patients with severe polypoid degeneration

This report summarizes our experiences with 23 women whose bilateral severe polypoid degeneration was managed surgically and who have been followed over a 2- to 7-year postoperative period. In our study group, polypoid degeneration did not reappear if the patient stopped smoking and practiced healthy vocal hygiene. About 25% of those who continued to smoke after surgery evidenced return of the disease, usually within 2 to 3 years. Reappearance of polypoid degeneration appeared most strongly related to the smoking variable alone or in combination with vocal abuse and/or medications that can cause edema. Neither vocal abuse nor medications appeared to be primary causal factors. The return of polypoid degeneration, in its earliest stages, was detected first via laryngeal examination.

Phonatory characteristics following surgical treatment of severe polypoid degeneration

This paper summarizes the results of our research into the efficacy of phonosurgery. Our study group consisted of 25 women whose severe, bilateral polypoid degeneration was managed surgically by one of the following methods: Hirano's technique, mechanical stripping, or CO2 laser enucleation. We found that all three procedures improved the voice. Surgery increased the average speaking fundamental frequency level substantially and improved the phonational range. Listeners' judgments about the appropriateness of vocal pitch and severity of hoarseness also changed positively following surgery. No one method was clearly better than another in improving the voice. However, patients treated using Hirano's method experienced the most rapid return of functional voice use, probably because the procedure is less traumatic and promotes more rapid healing than mechanical stripping or laser removal.

Comparison of surgical techniques in the treatment of laryngeal polypoid degeneration

Surgical excision has been the accepted treatment of laryngeal polypoid degeneration, or chronic polypoid corditis. We report on 29 women with polypoid degeneration who received one of three surgical treatments: vocal fold stripping, carbon dioxide laser obliteration, or the Hirano technique. The duration of postoperative dysphonia was longest with the laser removal and shortest with the Hirano technique. A combination of vocal hygiene management and the Hirano technique of removal provided the most efficacious treatment.

Chalcogenide glass bolometers

The chalcogenide glass Tl(2)SeAs(2) Te(3) has been evaluated as a thermistor bolometer material for room temperature operation. Thin film bolometers were fabricated on mica, glass, and sapphire substrates by both hot-pressing and rf sputtering techniques. Best results were achieved with 10-micro thick Tl(2)SeAs(2) Te(3) elements on thin mica substrates. Using a 500 K blackbody at a 10-Hz chopping frequency, a 2.5 x10(_3)cm(2) device yielded an NEP of 2.3 x 10(_9) W Hz(_4) cm(-2) device achieved an NEP of 7.7 x 10(-10) W Hz(-1/2) The ac performance of these devices is limited by their inherently long response times (tau congruent with 1 sec).