Ultra-Broadband CW Supercontinuum Generation Centered at 1483.4 nm from Brillouin/Raman Fiber Laser

Abstract

We analyze spectra obtained with the Spitzer Infrared Spectrograph (IRS) of 110 B-, A-, F-, and G-type stars with optically thin infrared excess in the Scorpius-Centaurus OB association. The ages of these stars range from 11 to 17 Myr. We fit the infrared excesses observed in these sources by Spitzer IRS and the Multiband Imaging Photometer for Spitzer (MIPS) to simple dust models according to Mie theory. We find that nearly all of the objects in our study can be fit by one or two belts of dust. Dust around lower mass stars appears to be closer in than around higher mass stars, particularly for the warm dust component in the two-belt systems, suggesting a massdependent evolution of debris disks around young stars. For those objects with stellar companions, all dust distances are consistent with truncation of the debris disk by the binary companion. The gaps between several of the two-belt systems can place limits on the planets that might lie between the belts, potentially constraining the mass and locations of planets that may be forming around these stars.

Optimized All-Fiber Supercontinuum Source at 1.3 $\mu \hbox{m}$ Generated in a Stepwise Dispersion-Decreasing-Fiber Arrangement

“…When the input power amounts to 4.73 W the spectral broadening starts to take place around 1315 nm. Earlier results have been reported on similar methods for the generation of cw SC emission [1], [2], [7], [21] which make use of a linear cavity configuration to shift the pump frequency into the anomalous dispersion region of the non-linear medium. It is worth to notice that, according to our results, a linear cavity is not strictly necessary to generate the spectral emission which will seed the SC broadening.…”

“…Supercontinuum (SC) generation in optical fibers from continuous-wave (cw) laser has been studied intensively in the last years, both experimentally [1]- [9] and theoretically [10]- [12]. These broadband, high power density and low-coherence light sources have been found to be extremely useful for optical coherence tomography (OCT) [13], [14].…”

Progress in Continuous-Wave Supercontinuum Generation

“…The first experimental demonstration of CW SC have been realized at the end of the nineties with a Raman laser launched in a standard telecommunication fiber. The spectral broadening was relatively restricted (around 200 nm) because it was mainly due to Raman effect Gonzalez-Herraez et al (2003); Persephonis et al (1996); Prabhu et al (2000). A breakthrough was reached a few years later when stronger pump lasers (from more than one order of magnitude) based on Ytterbium doped fibers were combined with photonic crystal fibers 4 www.intechopen.com (PCFs) owing a low group-velocity dispersion (GVD) value around the pump wavelength Avdokhin et al (2003).…”

Optical Coherence Tomography Based on a Continuous-wave Supercontinuum Seeded by Erbium-doped Fiber's Amplified Spontaneous Emission

“…On the other hand, SC was also found to be generated in the continuous-wave (CW) mode by using a partiallycoherent CW pump beam [10][11][12][13]. The physical mechanism for CW SC evolution in optical fiber is slightly different from pulse-mode SC evolution [10][11][12][13].…”

“…The physical mechanism for CW SC evolution in optical fiber is slightly different from pulse-mode SC evolution [10][11][12][13]. Modulation instability (MI) converts an initial, partially-coherent CW beam coupled into a nonlinear anomalous-dispersion fiber into large numbers of ultrashort soliton-like pulses.…”