Two-octave-spanning dispersion-controlled precision optics for sub-optical-cycle waveform synthesizers

Abstract

Two-octave-spanning precision dispersive mirror systems are demonstrated, providing a new enabling technology for pulse-energy and bandwidth scaling of sub-cycle optical waveform synthesizers. We propose and characterize new dispersion management schemes with advanced dielectric coating designs. Based on an analytic dual adiabatic matching structure, we implement a chirped dichroic mirror, to efficiently optimize the beam combining from different spectra, and a double-chirped mirror pair, to avoid unwanted nonlinearity during beam propagation, with custom-tailored dispersion and reflectivity over more than two octaves of bandwidth ranging from 0.49 to 2.3 μm, supporting 1.9-fs-short sub-optical-cycle pulses. The multilayer coating structures can also be applied to the design of chirped-fiber Bragg gratings and general optical filters. The proposed designs and schemes will benefit ultrabroadband applications requiring precise dispersion management, especially enabling the generation of intense sub-optical-cycle light transients

Toward Waveform Nonlinear Optics Using Multimillijoule Sub-Cycle Waveform Synthesizers

“…In [65], we recently introduced a dual-adiabatic-matching (DAM) mirror structure, that generates a double chirp not only in the front (as in DCMs) but also in the back section of the mirror approaching the substrate, thus adiabatically tapering the impedance again to provide high transmission for long wavelengths. The front and back chirped high-index layers perform dual adiabatic impedance matching, resulting in (1) high reflectivity and smooth GD over the high-reflectivity range and (2) high transmission with sidelobe suppression outside the high-reflectivity range, respectively.…”

Timing jitter characterization of a high-energy sub-cycle optical waveform synthesizer

“…We generate a common CEP-stable seed continuum (0.5-2.5 µm) [10] by white-light generation in a YAG crystal pumped by the second harmonic (1.06 µm) of the CEP-stable idler of a NIR OPA. The resulting continuum is then split with dichroic beam splitters [11] and seeds three OPA channels employing type-I BBO crystals, a VIS non-collinear OPA (NOPA), a NIR and an IR degenerate OPA (DOPA) channel, pumped by the fundamental wavelength pulses at 0.8 µm (IR DOPA) and by its second harmonic at 0.4 µm (VIS NOPA, NIR DOPA). Figure 1 shows the output spectra and pulse energies of the 3 channels obtained after 3 amplification stages each.…”

“…Figure 1 shows the output spectra and pulse energies of the 3 channels obtained after 3 amplification stages each. After parametric amplification, the three OPA channel outputs can individually be compressed, recombined and finally fully recompressed close to the Fourier limit inside the vacuum chamber using custom-designed precision dispersive mirrors [11]. To illustrate the precision and flexibility of our dispersion compensation scheme, we show in Fig.…”

“…We combined spatially and temporally the three OPA pulses after the third amplification stages (VIS NOPA3, NIR DOPA3, IR DOPA3) on custom-designed dichroic beam splitters [11], which have a ~5% leakage composed of the combined OPA pulses collinear with each other. This leakage is used for the balanced optical cross-correlator (BOC) setups, analogous to the ones described in [7,8].…”

High-Energy Sub-Optical-Cycle Parametric Waveform Synthesizer

“…In other words, the synthesis can later directly be performed from these pulses after locking their relative timing using feedback loops with balanced optical cross-correlators, that can achieve sub-cycle synchronization with <30-as RMS timing jitter [6]. The dispersion compensation scheme [10] includes custom-designed double-chirped mirror (DCM) pairs and dichroic beam splitters/combiners, plates and wedges (SiO 2 , ZnSe) for dispersion fine-tuning, and the CaF 2 window of our future experiment's vacuum chamber. The next step will be the waveform synthesis from all three channels at the mJ level.…”