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Prof. Fetah Benabid学术报告会-8月11日
发表时间:2016-08-10 阅读次数:1602次

报告时间:8月11日  14:00

报告地点:光学楼525室

题目:Kagome Fibre: a new paradigm in pulse compression and beam delivery of ultra-high Power Ultra-Short Pulsed Lasers

 

Abstract:

In 2002 the development of a new type of hollow-core photonic crystal fibre (HC-PCF), coined Kagome fibre, has been reported [1]. The fibre guides light via a new mechanism that doesn’t require a photonic bandgap in the fibre cladding [2]. This guidance mechanism, called Inhibited Coupling (IC), is the guided photonic analogue of the concept of bound or quasi-bound state in a continuum established within the field of solid-state quantum physics. The IC guidance offered a design tool to the seminal introduction of hypocycloid core-contour (i.e. negative curvature) hollow-core photonic crystal fibre [3,4], which allowed a dramatic reduction in transmission loss of IC guiding HC-PCF [5,6,7]. This improvement is such that IC guiding HC-PCF, which previous typical loss figure was in the range of 0.5-1 dB/m, outperforms photonic bandgap (PBG) guiding HC-PCF in optical transmission. Today, the lowest loss figures at the benchmark wavelengths of the NIR-VIS spectral range are all set by the hypocycloid core-contour (HCC) kagome HC-PCF. The records are 17 dB/km ~1μm wavelength [5], 70dB/km at ~780 nm [6] and 70 dB/km at 500-600 nm wavelength range [7], and more recently, using IC guiding tubular lattice HC-PCF, we demonstrated a loss as low as 7.7 dB/km at 750 nm [13].

 

Furthermore, because of the intrinsic properties of the IC guidance, the reduction in loss means systematically a reduction in the power-overlap with the silica core-surround. As a result unprecedented handling of laser pulse-energy and optical power is demonstrated with ultra-low transmission loss. This has been illustrated in the recent results in ultra-short pulse transportation and compression [8-11,5], leading to the record 1 mJ energy pulse delivery [5]. Here, 1 milli-Joule energy, gigawatt peak power and close-to pettawatt/cm2 intensity ultra-fast laser-pulses from 600 fs Yb fiber-laser were successfully guided and compressed in HC-PCF. The guidance was achieved with low loss and in a single-mode fashion, and the pulse compression is achieved in a self-compression manner. Another result in high optical-field is the self-compression down to sub-cycle regime of 80 fs USP operating at 1.8 μm and with several tens of μJ pulse-energy [11]. These results open exciting prospects in fibre based high field photonics and laser micromachining. As a matter of fact, IC guiding Kagome HC-PCF is currently commercially available from GLOphotonics [12] and is strongly used as a fibre beam delivery of high power ultra-short pulse lasers.

 

References
1. Benabid et al. Science 298, 399 (2002)
2. Couny et al., Science318, 1118 (2007)
3. Wang et al., in CLEO 2010, OSA Technical Digest, postdeadline paper CPDB4. (2010)
4. Wang et al., Opt. Lett. 36, 669 (2011)
5. Debord et al, Opt. Express, 21, 28597 (2013)
6. Bradley et al, J. Lightwave Tech., 3, 2752(2013)
7. Debord et al, Postdeadline paper in CLEO 2014
8. Heckl et al., Opt. Express 19, 19142(2011)
9. Wang et al, Opt. Lett. 37,3111 (2012)
10. Emaury et al. Opt. Express, 21, 4986-4994 (2013)
11. Balciunas et al. T. Balciunas et al., Nat Commun, vol. 6, Jan. 2015, and in Advanced Solid-State Lasers Congress 2013, postdeadline paper JTh5A.5 (2013).
12. www://http.glophotonics.fr
13. Debord et al. postdeadline paper. JTh4C-8, CLEO (2016)

 

 

Introduction of the speaker:
Fetah Benabid is a CNRS director of research and honorary professor at the universities of Bath (UK) and Western Australia (Australia). He is the group founder and leader of Gas-Phase Photonic and Microwave Materials (GPPMM) at the CNRS UMR Xlim, Limoges, France. Fetah Benabid has pioneered the development of hollow-core photonic crystal fibres (HC-PCF) and their incorporation into scientific and technological applications. He is the inventor of Kagome HC-PCF and an all-fibre gas cells, coined photonic microcell (PMC). He is the inceptor of new optical guidance mechanism called inhibited coupling optical guidance that led to low loss optical fiber with negative curvature core-contour, and the “photonic tight-binding model” to explain the formation of photonic bandgap in photonic crystal fibres. Fetah Benabid research interests covers guided photonics, gas-phase based nonlinear and coherent optics. Fetah Benabid is also the founder of the start-up GLOphotonics market leader in hollowcore fibers for industrial applications. He is an OSA fellow and the Fresnel Prize recipient.

 

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