Optical pulse compression to 34fs in the monocycle region by feedback phase compensation

Abstract

We compensated for chirp of optical pulses with an over-one-octave bandwidth (495 -1090 nm; center wavelength of 655.4 nm) produced by self-phase modulation in a single argon-filled hollow fiber and generated 3.4-fs, 1.56 optical-cycle pulses (500 nJ, 1-kHz repetition rate). This was achieved with a feedback system combined with only one 4-f phase compensator with a spatial light modulator and a significantly improved phase characterizer based on modified spectral phase interferometry for direct electric-field reconstruction. To the best of our knowledge, this is the shortest pulse in the visible-to-infrared region.

Comparison between Finite-Difference Time-Domain Method and Experimental Results for Femtosecond Laser Pulse Propagation

“…The spectrum, temporal intensity profile, and pulse width after phase compensation results as calculated by the extended FDTD method agree well with those obtained in our previous experiment. These findings indicate that the combination of this extended FDTD method and the group delay compensation simulation is robust for estimating the spectrum, the temporal pulse profile after propagation through a fiber and the shortest pulse obtained by compensation, and is useful for estimating the shortest pulse when the fiber-compression system is designed to obtain a single-cycle pulse (Yamane et al, 2003). When the extended FDTD method is established as the ultrashort optical pulse propagation analysis technique, its application to the characteristic analysis of an ultrahigh-speed optical switch, the propagation characteristic analysis of the optical pulse in a photonic crystal, and nonlinear propagation analysis in a photonic crystal fiber or a taper fiber are expected.…”

“…The 4-f system consisted of two spherical mirrors and two reflective gratings (Nakamura et al, 2002a), ), (Yamane et al, 2003). The optical path lengths from the gratings to the spherical mirrors with a focal length f and those from the spherical mirrors to the SLM are all set to be f. The liquid crystal SLM (Citizen Company) ) consisted of 648 97−μm-wide pixels, with a 5 μm gap between adjacent pixels.…”

“…A recent report by Kalosha and Herrmann considers the linear dispersion with two resonant frequencies and the nonlinear terms without the Raman effect (Kalosha & Herrmann, 2000). For the single-cycle pulse generation experiment, we must use at least the shortest pulse of 3.4 fs (Yamane et al, 2003) or sub-5 fs ), (Cheng et al, 1998) or the commercially available 12 fs pulses. Such a time regime is comparable to the…”

Attosecond‐precision ultrafast photonics

“…For further investigations and applications of such phase-sensitive phenomena [11,12,[48][49][50][51][52][53][54], a single-cycle optical pulse, comprising only one cycle of the light oscillation, has been pursued in many laboratories. Different approaches include cascaded Raman sideband generation [55], broadband optical parametric amplification [56], and external compression [57][58][59]. To synthesize singlecycle pulses, several groups have worked on the synthesis of optical combs that span the visible to infrared ranges by synchronizing two broadband mode-locked lasers with different center wavelengths [40,60,61] or by synchronizing an optical parametric oscillator and its mode-locked pump laser [62,63].…”

Spatial optimization of filaments

“…From other experiments [53,54] we know that octave-broad spectra in the visible/NIR and compression down to < 4f s have been successfully demonstrated. However, the energy of the dramatically shortened pulses is mostly on the order of less than 300µJ.…”