Attosecond science capitalizes on the extreme nonlinearity of strong fields—driven by few-cycle pulses—to attain attosecond temporal resolution and give access to the electron motion dynamics of ...matter in real time. Here we measured the relative electronic delay response of a dielectric system triggered by a strong field of few-cycle pulses to be of the order of a few hundred attoseconds. Moreover, we exploited the electronic response following the strong driver field to demonstrate all-optical light-field-sampling methodology with attosecond resolution. This methodology provides a direct connection between the driver field and induced ultrafast dynamics in matter. Also, we demonstrate control of electron motion in a dielectric using synthesized light waveforms. This on-demand control of electron motion paves the way for establishing long-anticipated ultrafast switches and quantum electronics. This advancement promises to increase the limiting speed of data processing and information encoding to rates that exceed one petabit per second, opening a new realm of information technology.Light-field-induced electron dynamics in a silicon dioxide dielectric system are exploited to directly measure the attosecond relative electronic delay response in the dielectric system, potentially extending the speed of data processing and information encoding into the petahertz realm.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Spectral broadening in bulk material is a simple, robust and low-cost method to extend the bandwidth of a laser source. Consequently, it enables ultrashort pulse compression. Experiments with a 38 ...MHz repetition rate, 50 W average power Kerr-lens mode-locked thin-disk oscillator were performed. The initially 1.2 μJ, 250 fs pulses are compressed to 43 fs by means of self-phase modulation in a single 15 mm thick quartz crystal and subsequent chirped-mirror compression. The losses due to spatial nonlinear effects are only about 40 %. A second broadening stage reduced the Fourier transform limit to 15 fs. It is shown that the intensity noise of the oscillator is preserved independent of the broadening factor. Simulations manifest the peak power scalability of the concept and show that it is applicable to a wide range of input pulse durations and energies.
The measurement and control of light field oscillations enable the study of ultrafast phenomena on sub-cycle time scales. Electro-optic sampling (EOS) is a powerful field characterization approach, ...in terms of both sensitivity and dynamic range, but it has not reached beyond infrared frequencies. Here, we show the synthesis of a sub-cycle infrared-visible pulse and subsequent complete electric field characterization using EOS. The sampled bandwidth spans from 700 nm to 2700 nm (428 to 110 THz). Tailored electric-field waveforms are generated with a two-channel field synthesizer in the infrared-visible range, with a full-width at half-maximum duration as short as 3.8 fs at a central wavelength of 1.7 µm (176 THz). EOS detection of the complete bandwidth of these waveforms extends it into the visible spectral range. To demonstrate the power of our approach, we use the sub-cycle transients to inject carriers in a thin quartz sample for nonlinear photoconductive field sampling with sub-femtosecond resolution.
We present directly oscillator-driven self-compression inside an all-bulk Herriott-type multi-pass cell in the near-infrared spectral range. By utilizing precise dispersion management of the ...multi-pass cell mirrors, we achieve pulse compression from 300 fs down to 31 fs at 11 µJ pulse energy and 119 W average power with a total efficiency exceeding 85%. This corresponds to an increase in peak power by more than a factor of three and a temporal compression by almost a factor of ten in a single broadening stage without necessitating subsequent dispersive optics for temporal compression. The concept is scalable towards millijoule pulse energies and can be implemented in visible, near-infrared and infrared spectral ranges. Importantly, it paves a way towards exploiting Raman soliton self-frequency shifting, supercontinuum generation and other highly nonlinear effects at unprecedented high peak power and pulse energy levels.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We demonstrate nonlinear pulse compression by multi-pass cell spectral broadening (MPCSB) from 860 fs to 115 fs with compressed pulse energy of 7.5 µJ, average power of 300 W and close to ...diffraction-limited beam quality. The transmission of the compression unit is >90%. The results show that this recently introduced compression scheme for peak powers above the threshold for catastrophic self-focusing can be scaled to smaller pulse energies and can achieve a larger compression factor than previously reported. Good homogeneity of the spectral broadening across the beam profile is verified, which distinguishes MPCSB among other bulk compression schemes.
High harmonic generation (HHG) enables extreme-ultraviolet radiation with table-top set-ups. Its exceptional properties, such as coherence and (sub)-femtosecond pulse durations, have led to a ...diversity of applications. Some of these require a high photon flux and megahertz repetition rates, for example, to avoid space charge effects in photoelectron spectroscopy. To date, this has only been achieved with enhancement cavities. Here, we establish a novel route towards powerful HHG sources. By achieving phase-matched HHG of a megahertz fibre laser we generate a broad plateau (25 eV-40 eV) of strong harmonics, each containing more than 1 × 1012 photons s-1 , which constitutes an increase by more than one order of magnitude in that wavelength range. The strongest harmonic (H25, 30 eV) has an average power of 143 μW (3 × 1013 photons s-1 ). This concept will greatly advance and facilitate applications in photoelectron or coincidence spectroscopy, coherent diffractive imaging or (multidimensional) surface science.
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Peak and average power scalability is the key feature of advancing femtosecond laser technology. Today, near-infrared light sources are capable of providing hundreds of Watts of average power. These ...sources, however, scarcely deliver pulses shorter than 100 fs which are, for instance, highly beneficial for frequency conversion to the extreme ultraviolet or to the mid- infrared. Therefore, the development of power scalable pulse compression schemes is still an ongoing quest. This article presents the compression of 90 W average power, 190 fs pulses to 70 W, 30 fs. An increase in peak power from 18 MW to 60 MW is achieved. The compression scheme is based on cascaded phase-mismatched quadratic nonlinearities in BBO crystals. In addition to the experimental results, simulations are presented which compare spatially resolved spectra of pulses spectrally broadened in self-focusing and self-defocusing media, respectively. It is demonstrated that balancing self- defocusing and Gaussian beam convergence results in an efficient, power-scalable spectral broadening mechanism in bulk material.
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We have temporally characterized, dispersion compensated and carrier-envelope phase stabilized 1.4-cycle pulses (3.2 fs) with 160 µJ of energy at 722 nm using a minimal and convenient dispersion-scan ...setup. The setup is all inline, does not require interferometric beamsplitting, and uses components available in most laser laboratories. Broadband minimization of third-order dispersion using propagation in water enabled reducing the compressed pulse duration from 3.8 to 3.2 fs with the same set of chirped mirrors. Carrier-envelope phase stabilization of the octave-spanning pulses was also performed by the dispersion-scan setup. This unprecedentedly simple and reliable approach provides reproducible CEP-stabilized pulses in the single-cycle regime for applications such as CEP-sensitive spectroscopy and isolated attosecond pulse generation.
We study coherence properties of a χ(²) optical parametric oscillator (OPO), which produces 2/3-octave-wide spectrum centered at the subharmonic (3120 nm) of the femtosecond pump laser. Our method ...consists of interfering the outputs of two identical, but independent OPOs pumped by the same laser. We demonstrate that the two OPOs show stable spatial and temporal interference and are mutually locked in frequency and in phase. By observing a collective heterodyne beat signal between the two OPOs we show that one can deterministically choose, by cavity length adjustment, between the two frequency states corresponding to the two sets of modes shifted with respect to each other by half of the laser pulse repetition rate. Moreover, we observe that the existence of two opposite phase states, a known common feature of a parametrically driven n = 2 subharmonic oscillator, reveals itself in our experiment as a common phase, 0 or π, being established through the whole set of some 300 thousand longitudinal modes.
Attosecond light field synthesis Alqattan, Husain; Hui, Dandan; Pervak, Vladimir ...
APL photonics,
04/2022, Volume:
7, Issue:
4
Journal Article
Peer reviewed
Open access
The advancement of the ultrafast pulse shaping and waveform synthesis allowed to coherently control the atomic and electronic motions in matter. The temporal resolution of the waveform synthesis is ...inversely proportional to the broadening of its spectrum. Here, we demonstrate the light field synthesis of high-power waveforms spanning two optical octaves, from near-infrared to deep-ultraviolet with attosecond resolution. Moreover, we utilized the all-optical field sampling metrology for on-demand tailoring of light field waveforms to control the electron motion in matter. The demonstrated synthesis of the light field and the electron motion control pave the way for switching the photo-induced current signal in dielectric nanocircuit and establishing ultrafast photonics operating beyond the petahertz speed.
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