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Jonathan C. Knight, is a British physicist. He is the Pro Vice-Chancellor (Research) for the University of Bath where he has been Professor in the Department of Physics since 2000, and served as head of department. From 2005 to 2008, he was founding Director of the university's Centre for Photonics and Photonic Materials.
A tapered double-clad fiber (T-DCF) is a double-clad optical fiber which is formed using a specialised fiber drawing process, in which temperature and pulling forces are controlled to form a taper along the length of the fiber. By using pre-clad fiber preforms both the fiber core and the inner and outer cladding layers vary in diameter and thickness along the full length of the fiber. This tapering of the fiber enables the combination of the characteristics of conventional 8–10 µm diameter double-clad single-mode fibers to propagate light in fundamental mode with those of larger diameter (50–100 µm) double-clad multi-mode fibers used for optical amplification and lasing. The result is improved maintenance of pulse fidelity compared to conventional consistent diameter fiber amplifiers. By virtue of the large cladding diameter T-DCF can be pumped by optical sources with very poor brightness factor such as laser diode bars or even VECSELs matrices, significantly reducing the cost of fiber lasers/amplifiers.
Baruch Fischer is an Israeli optical physicist and Professor Emeritus in the Andrew and Erna Viterbi Faculty of Electrical and Computer Engineering of the Technion, where he was the Max Knoll Chair in Electro-Optics and Electronics.
References
- ↑ Zhao, Jianhui; Liu, Xiaoming (1 May 2006). "Fiber acousto-optic mode coupling between the higher-order modes with adjacent azimuthal numbers". Optics Letters. The Optical Society. 31 (11): 1609–1611. Bibcode:2006OptL...31.1609Z. doi:10.1364/ol.31.001609. ISSN 0146-9592. PMID 16688236.
- ↑ Thomas, Jens; Jovanovic, Nemanja; Becker, Ria G.; Marshall, Graham D.; Withford, Michael J.; Tünnermann, Andreas; Nolte, Stefan; Steel, M. J. (22 December 2010). "Cladding mode coupling in highly localized fiber Bragg gratings: modal properties and transmission spectra". Optics Express. The Optical Society. 19 (1): 325–341. arXiv: 1011.2691 . doi: 10.1364/oe.19.000325 . ISSN 1094-4087. PMID 21263572.
- ↑ See e.g. R. Paschotta, Mode coupling, in the online Encyclopedia of Laser Physics and Technology, https://www.rp-photonics.com/mode_coupling.html
- ↑ See e.g. W. Götze, Complex Dynamics of glass forming liquids. A mode-coupling theory, Oxford: Oxford University Press (2009).