Scalar generalized nonlinear Schrödinger equation-quantified continuum generation in an all-normal dispersion photonic crystal fiber for broadband coherent optical sources

Abstract

We quantitatively predict the observed continuum-like spectral broadening in a 90-mm weakly birefringent all-normal dispersion-flattened photonic crystal fiber pumped by 1041-nm 229-fs 76-MHz pulses from a solid-state Yb:KYW laser. The well-characterized continuum pulses span a bandwidth of up to 300 nm around the laser wavelength, allowing high spectral power density pulse shaping useful for various coherent control applications. We also identify the nonlinear polarization effect that limits the bandwidth of these continuum pulses, and therefore report the path toward a series of attractive alternative broadband coherent optical sources.

Suppressing Short-Term Polarization Noise and Related Spectral Decoherence in All-Normal Dispersion Fiber Supercontinuum Generation

“…The unintentional latent birefringence of these nonlinear fibers, although small, defines a distinct slow axis along which linearly polarized SC output can be produced when a polarized input is launched along this axis, i.e., the SC generation can be effectively polarization-maintaining [12]. However, above a certain threshold of output power, this SC suffers a hardly controllable nonlinear depolarization effect [12–14], so that the spectrum of the SC defies the scalar generalized nonlinear Schrödinger equation (GNLSE) [13] and the polarization of the SC endures long-term instability [14].…”

“…However, above a certain threshold of output power, this SC suffers a hardly controllable nonlinear depolarization effect [12–14], so that the spectrum of the SC defies the scalar generalized nonlinear Schrödinger equation (GNLSE) [13] and the polarization of the SC endures long-term instability [14]. In these prior works, the depolarization effect has been attributed to vector modulation instability [3,15].…”

Label-free optical imaging technologies for rapid translation and use during intraoperative surgical and tumor margin assessment

“…21,41,42 Journal of Biomedical Optics 021104-5 February 2018 • Vol. 23 (2) Recently, Tu et al 43 and Tu and Boppart 44 developed a platform system based on a pumped photonic crystal fiber source that produced widely coherent supercontinuum suitable for pulse compression and shaping to efficiently drive label-free nonlinear processes of two-and three-photon autofluorescence, secondand third-harmonic generation, and broadband hyperspectral coherent anti-Stokes Raman scattering. 45 This multimodal platform imaging system was able to simultaneously capture all channels for spatially and temporally correlated images of autofluorescent molecules associated with metabolism and cell function (NADH and FAD), microstructural organizational features of collagen and elastin, cellular and subcellular interfaces, and compositional molecular differences throughout tissue.…”

Nonlinear Interferometric Vibrational Imaging (NIVI) with Novel Optical Sources

“…Unfortunately, few known fiber continuum sources have sufficient coherence, bandwidth, or power for coherent control. We have developed an Yb laser-pumped fiber continuum [44,47,48], with broad bandwidth (880-1,180 nm), high average power (361 mW), and excellent coherence (Fig. 39.9a, b).…”