arXiv subjects

Kevin Zawilski

Publications and source records attributed to Kevin Zawilski.

3 recordsLinked to original sources

arXiv2022

High quantum efficiency parametric amplification via hybridized nonlinear optics

Parametric amplifiers have allowed breakthroughs in ultrafast, strong-field, and high-energy density laser science and are an essential tool for extending the frequency range of powerful emerging diode-pumped solid-state laser technology. However, their impact is limited by inherently low quantum efficiency due to nonuniform light extraction. Here we demonstrate a new type of parametric amplifier based on hybridized nonlinear optics. Hybridization of parametric amplification with idler second harmonic generation induces unusual evolution dynamics for a fully parametric amplifier - with saturating rather than cyclic gain - observed here for the first time. This allows highly uniform light extraction enabling unprecedented efficiency for a lossless amplifier with Gaussian-like intensity profiles - a 48-dB single-stage gain with 68% quantum efficiency and 44% pump-to-signal energy conversion - a several-fold improvement over the standard. Possessing both laser-like high quantum efficiency and the advantages of thermal-loading free parametric systems, this simple approach can be implemented widely and have significant impact by increasing several-fold the power available for science and industry.

physics.optics↗

arXiv2019

Table-top high-energy 7 um OPCPA and 260 mJ Ho:YLF pump laser

We present the state of the art of a compact high-energy mid-infrared laser system for TW-level 8-cycle pulses at 7 um. This system consists of an Er:Tm:Ho:fiber MOPA which serves as the seeder for a ZGP-based OPCPA chain in addition to a Ho:YLF amplifier which is Tm:fiber pumped. Featuring all-optical synchronization, the system delivers 260-mJ pump energy at 2052 nm, 16-ps duration at 100 Hz with a stability of 0.8 % rms over 20 min. We show that chirp inversion in the OPCPA chain leads to excellent energy extraction and aids in compression of the 7-um pulses to 8 optical cycles (188 fs) in bulk BaF2 with 93.5 % efficiency. Using 21.7 mJ of the available pump energy, we generate 0.75-mJ-energy pulses at 7 um due to increased efficiency with a chirp-inversion scheme. The pulse quality of the system's output is shown by generating high harmonics in ZnSe which span up to harmonic order 13 with excellent contrast. The combination of the passive carrier-envelope phase stable mid-infrared seed pulses and the high-energy 2052 nm picosecond pulses makes this compact system a key enabling tool for the next generation of studies on extreme photonics, strong field physics and table-top coherent X-ray science.

physics.optics↗

arXiv2017

High-energy mid-infrared sub-cycle pulse synthesis from a parametric amplifier

High-energy, carrier-envelope phase (CEP)-stable, sub-cycle, mid-infrared (mid-IR) pulses can provide unique opportunities of exploring phase-sensitive strong-field light-matter interactions in atoms, molecules, and solids. In the mid-IR wavelength, the ponderomotive energy of laser pulses is dramatically increased (versus the visible/near-infrared) and, therefore, the Keldysh parameter is much smaller than unity even at relatively modest laser intensities. This enables to study the sub-cycle electron dynamics in solids via high-harmonic generation (HHG) without damage. One can also control the electron emissions from nano-devices in the sub-cycle time scale. These efforts are opening a great opportunity towards petahertz electronics. Here, we present a high-energy, sub-cycle pulse synthesizer based on a mid-IR optical parametric amplifier (OPA), pumped by CEP-stable, 2.1 um femtosecond pulses, and its application to HHG in solids. The signal and idler combined spectrum spans from 2.5 to 9.0 um, which covers the whole midwave-infrared (MWIR) region. We coherently synthesize the passively CEP-stable few-cycle signal and idler pulses to generate 33 uJ, 0.88-cycle (12.4 fs), multi-GW pulses centered at ~4.2 um, which is further energy scalable. The in-line synthesis of the CEP-stable sub-cycle pulse is realized through the type-I collinear OPA with minimal temporal walk-off. The MWIR sub-cycle pulse is used for driving HHG in thin silicon samples, producing harmonics up to ~19th order with a continuous spectral coverage due to the isolated emission by the sub-cycle driver. Our demonstration offers an energy scalable and technically simple platform of laser sources generating CEP-stable sub-cycle pulses in the whole MWIR region for investigating isolated phase-sensitive strong-field interactions in solids and gases.

physics.optics↗