Mid-Infrared Octave-Spanning Supercontinuum and Frequency Comb Generation in a Suspended Germanium-Membrane Ridge Waveguide

Abstract

(2017) Mid-infrared octave-spanning supercontinuum and frequency comb generation in a suspended germanium-membrane ridge waveguide. Journal of Lightwave Technology, 35 (14 Northumbria University has developed Northumbria Research Link (NRL) to enable users to access the University's research output. Copyright © and moral rights for items on NRL are retained by the individual author(s) and/or other copyright owners. Single copies of full items can be reproduced, displayed or performed, and given to third parties in any format or medium for personal research or study, educational, or not-for-profit purposes without prior permission or charge, provided the authors, title and full bibliographic details are given, as well as a hyperlink and/or URL to the original metadata page. The content must not be changed in any way. Full items must not be sold commercially in any format or medium without formal permission of the copyright holder. The full policy is available online: http://nrl.northumbria.ac.uk/policies.html This document may differ from the final, published version of the research and has been made available online in accordance with publisher policies. To read and/or cite from the published version of the research, please visit the publisher's website (a subscription may be required.) > REPLACE THIS LINE WITH YOUR PAPER IDENTIFICATION NUMBER (DOUBLE-CLICK HERE TO EDIT) < 1 Abstract-Stable octave-spanning supercontinuum (SC) in the mid-infrared (MIR) region finds extensive applications in spectroscopy, metrology, biochemistry, etc. The absorption of conventional silicon-or silicon oxide-dominated nonlinear media makes SC generation in MIR region technically challenging. In this paper, we propose ultra-broadband MIR-SC generation using a suspended germanium-membrane ridge waveguide. We theoretically showed that when pump pulses centered at 4.8 m with pulse width at 180 fs and peak power at 800 W are injected into a 4-mm long proposed ridge waveguide, the SC generated ranges from 1.96  12 m (about 2.6 octaves), extending deep into the "fingerprint" region. The first-order coherence is calculated to confirm the stability of the generated SC. The performance of the SC-based frequency comb is also investigated by assuming a 100-pulses pump source at a repetition rate of 100 KHz.

Highly coherent supercontinuum generation in a polarization-maintaining CS2-core photonic crystal fiber

“…where c represents the light velocity in vacuum. γ(z) is the Kerr nonlinear coefficient, which can be calculated by integration over the cross-section of the fiber as [1,39]…”

“…Supercontinuum (SC) generation has been attracting great research interests because of its extensive applications in wavelength-tunable light source, optical communication, optical coherence tomography [1][2][3][4]. The physical mechanism of the SC generation is resulted from a variety of nonlinear effects such as self-phase modulation (SPM), simulated Raman scatting (SRS), four-wave mixing (FWM), soliton fission (SF), etc.…”

“…The physical mechanism of the SC generation is resulted from a variety of nonlinear effects such as self-phase modulation (SPM), simulated Raman scatting (SRS), four-wave mixing (FWM), soliton fission (SF), etc. [1,[5][6][7]. The SC can be generated when pump pulse is respectively launched into the normal and anomalous dispersion regions of the nonlinear media [8,9].…”

Mid-Infrared Self-Similar Pulse Compression in a Tapered Tellurite Photonic Crystal Fiber and Its Application in Supercontinuum Generation

“…9(a), the temporal and spectral profiles are not sensitive to the noise seed since the MI is suppressed by the self-similar compression, and the coherence of the SC is greatly enhanced. To compare the coherence of the SCs generated with the 1 ps and 62.16 fs pulses, we use the degree of coherence (1) 12 g to characterize the output spectra of the SC which is defined as [34], [44]- [45] A λ tAλ t g λ, t t A λ tA λ t (11) where A(λ, t) represents the signal amplitude in the frequency domain. The angular brackets represent the ensemble average over independently pairs of spectra, i.e.…”

Mid-infrared self-similar compression of picosecond pulse in an inversely tapered silicon ridge waveguide

“…Optical pulse compression technique is important for many applications, including optical communication, nonlinear microscopy, supercontinuum and frequency comb generations [1][2][3][4][5][6], etc. In laser systems, prism or grating-based compressors are typically used to compensate the linear chirp of pulses to compress them [7][8][9].…”