Cross-validation of theoretically quantified fiber continuum generation and absolute pulse measurement by MIIPS for a broadband coherently controlled optical source

Abstract

The predicted spectral phase of a fiber continuum pulsed source rigorously quantified by the scalar generalized nonlinear Schrödinger equation is found to be in excellent agreement with that measured by multiphoton intra-pulse interference phase scan (MIIPS) with background subtraction. This cross-validation confirms the absolute pulse measurement by MIIPS and the transform-limited compression of the fiber continuum pulses by the pulse shaper performing the MIIPS measurement, and permits the subsequent coherent control on the fiber continuum pulses by this pulse shaper. The combination of the fiber continuum source with the MIIPS-integrated pulse shaper produces compressed transform-limited 9.6 fs (FWHM) pulses or arbitrarily shaped pulses at a central wavelength of 1020 nm, an average power over 100 mW, and a repetition rate of 76 MHz. In comparison to the 229-fs pump laser pulses that generate the fiber continuum, the compressed pulses reflect a compression ratio of 24.

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

“…1). The pulse compression was conducted by a 640-pixel 4f pulse shaper (MIIPSBox 640, BioPhotonic Solutions Inc.), which employed the pulse measurement of multiphoton intrapulse interference phase scans (MIIPS) [17,18] to iteratively compress the SC pulse [9,19]. Alternative pulse measurements based on FROG [20] and SPIDER [21,22] have also enabled the iterative compression of other fiber SC pulses by similar 4f pulse shapers.…”

“…Thus, the input quantum noise is not amplified, i.e., the spectral decoherence is not accumulated to disrupt high-quality pulse compression [4]. Inspired by the 1999 innovation of hybrid anomalous-normal dispersion (HANDi) fiber SC generation that has enabled wide access to ultra-broadband laser-like sources [5], recently revived efforts in the ANDi fiber SC generation have claimed to develop various low-noise coherent SC sources by coupling common nJ-level ~100 fs input pulses into dispersion-flattened Ge-doped circular fibers [6], pure-silica photonic crystal fibers [7–9], and soft-glass all-solid microstructured fibers [10]. Octave-spanning bandwidth has been attained to center at 1550 nm [6,10], 1050 nm [7,8], and 800 nm [8].…”

“…Octave-spanning bandwidth has been attained to center at 1550 nm [6,10], 1050 nm [7,8], and 800 nm [8]. The low optical noise has been confirmed by relative intensity noise (RIN) measurements [6] and ultrafast transient absorption spectroscopy [8], while the high coherence by spectral interference [6] and pulse compression [7,9]. These experiments are highly consistent with theoretical analysis [11], reinforcing the general notion that the ANDi fiber SC sources are not limited by optical noise or decoherence [4].…”

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).…”

“…This degree of predictability and controllability allows us to compress and arbitrarily shape the fiber continuum using an MIIPS-assisted 4-f pulse shaper (Fig. 39.9c) [48] and to conduct multimodal multiphoton imaging on biological samples. Also, MIIPS adaptively compensates for the transmission optics and microscope objective after the shaper (Fig.…”