1,721,771 research outputs found
A new genus and species of primary freshwater crab and a new species of Artopotamon Dai & Chen, 1985 (Crustacea, Brachyura, Potamidae) from western Yunnan, China
No full textChu, Kelin, Wang, Pengfei, Sun, Hongying (2018): A new genus and species of primary freshwater crab and a new species of Artopotamon Dai & Chen, 1985 (Crustacea, Brachyura, Potamidae) from western Yunnan, China. Zootaxa 4422 (1): 115-131, DOI: 10.11646/zootaxa.4422.1.
A high-T high-resolution thermometer based on a microfiber coupler tip
No full textA compact thermometer based on a broadband microfiber coupler tip is demonstrated in this paper. The thermometer can measure a broad temperature range from room temperature to 1283°C. This is the highest temperature measured with a silica optical fiber device. An average sensitivity of 11.96pm/°C was achieved for a coupler tip diameter of ~3 µm
Fast-response high-temperature microfiber coupler tip thermometer
Full text linkA compact temperature sensor based on a broadband microfiber coupler tip is demonstrated. The thermometer dynamic range spans from room temperature to 1511°C with a response time of tens of ms. This is the highest temperature measured with a silica optical fiber device. A resolution of 0.66°C was achieved for a coupler tip diameter of ~12.56 µm. Better resolution can be achieved with smaller size microfiber coupler tips
A fast-response microfiber coupler tip high temperature sensor
No full textA compact fast temperature sensor based on a broadband microfiber coupler tip is demonstrated. The thermometer dynamic range spans from room temperature to 1511 °C with a response time of tens of ms. This is the highest temperature measured with an optical fiber device. The resolution of 0.66 °C was achieved for a coupler tip diameter of ~12.56 µm
High-sensitivity, fast-response ethanol gas optical sensor based on a dual microfiber coupler structure with the Vernier effect
No full textA high-sensitivity ethanol gas sensor based on two microfiber couplers and the Vernier effect is examined in this Letter using the unique variation rate conversion point characteristics. The output spectrum of the two couplers connected in parallel are superimposed to form a symmetrical envelope curve, showing high responsivity to variations in the external environment. Ethanol sensitivity was achieved by coating the waist region of the coupler with a mixture of Nile red and polymethyl methacrylate. When the concentration of ethanol gas changes, the envelope spectrum shifts. Experimental results show that a high responsivity of 160 pm/ppm can be obtained by tracing the reference peaks in the envelope curve and that the response and recovery times are on the order of seconds.</p
A compact temperature sensor based on micrometric optical fiber coupler tip
No full textA compact temperature sensor based on a coupler tip with micrometric size is demonstrated. This sensor can measure a temperatures as high as 1283 °C with an average sensitivity of ~12 pm/°C
A microfiber coupler tip thermometer
Full text linkA compact thermometer based on a broadband microfiber coupler tip is demonstrated. This sensor can measure a broad temperature interval ranging from room temperature to 1283 °C with sub-200 µm spatial resolution. An average sensitivity of 11.96 pm/°C was achieved for a coupler tip with ~2.5 µm diameter. This is the highest temperature measured with a silica optical fiber device
Focused ion beam engraved phase-shifted Bragg grating microcavity resonator
No full textA cavity with minimal-volume confinement was created in a microfiber engraving a high-contrast phase-shifted Bragg grating by focused ion beam. While waveguiding by the air/silica boundary provides a diffraction-limited 2D confinement, the grating introduces the third degree of confinement. Theoretical simulations verified the phase-shifted cavity confinement and showed a reasonable agreement with the experimental demonstration. This cavity can find a variety of applications ranging from sensing to quantum dynamic experiments
A fiber tip refractive index sensor using FIB-milled gold-coated singlemode-multimode-singlemode structure
No full textA compact fiber tip refractive index sensor using FIB-milled gold-coated singlemode-multimode-singlemode structure is demonstrated. Focused ion beam (FIB) is exploited to cut the fiber tip to obtain a flat end-face and then a layer of gold is coated on the tip surface, to increase its reflection. An average sensitivity of 265 nm/RIU is obtained experimentally with a ~2.94 µm diameter singlemode-multimode-singlemode fiber tip (SMST). Because of several advantages, including compactness, ease of fabrication, linear response, high sensitivity, easy connection with other fiberized optical components and low cost, this refractive index sensor could find various applications in chemical and biological area
Design of an extra-low-loss broadband Y-branch waveguide splitter based on a tapered MMI structure
No full textAn optimal design for an extra-low loss buried waveguide Y-branch splitter is presented over a broadband wavelength range from 1500~1600 nm. A tapered multimode waveguide section, earlier used to reduce the excess loss, is optimized when the light distribution at the end of the multimode waveguide section is matched to the profile of the symmetric supermode for the structure of the two branching waveguides. An optimization that combines genetic algorithm and a gradient-based search method are used to obtain the optimal geometrical parameters for the multimode waveguide section as well as the widths for the input and branching waveguides. An excess loss of 0.015 dB @1550 nm was obtained after the proposed optimization. For these optimized parameters, even when packaging induces a typical offset between input standard singlemode fibre and waveguide, the wavelength dependence of the output ratio between the two branches is small (less than 0.03 dB)
- …
