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Measurement of Scattering Nonlinearities from a Single Plasmonic Nanoparticle
Published on: January 3, 2016
Spectral features and modeling of high-order harmonics generated by sub-10-fs pulses
Villoresi1, Ceccherini, Poletto
1Istituto Nazionale Fisica della Materia, Laboratorio di Elettronica Quantistica-D.E.I., Universita di Padova, Padova, Italy.
Physical Review Letters
|September 8, 2000
Summary
Investigating harmonic radiation from neon gas jets with ultrashort laser pulses revealed unique spectral features. A numerical model accurately reproduced these experimental findings, confirming the quasi-single-cycle excitation regime.
Area of Science:
- Atomic, Molecular, and Optical Physics
- Nonlinear Optics
- Quantum Electronics
Background:
- High-harmonic generation (HHG) is a crucial process for producing coherent extreme ultraviolet (XUV) and soft X-ray radiation.
- Understanding the influence of laser pulse duration and medium properties is essential for controlling HHG spectra.
- Previous studies have explored HHG in various media, but the quasi-single-cycle regime in neon requires further investigation.
Purpose of the Study:
- To experimentally and theoretically investigate harmonic radiation generated in a neon gas jet using sub-10-femtosecond laser pulses.
- To analyze the spectral profile, intensity, and relative spectral shifts of generated harmonics.
- To explore the impact of gas jet position on harmonic emission characteristics.
Main Methods:
- Experimental measurements of harmonic spectra as a function of gas jet position.
- Theoretical investigation using a non-adiabatic three-dimensional numerical model.
- Comparison of experimental results with theoretical predictions.
Main Results:
- Observed spectral features characteristic of the quasi-single-cycle excitation regime.
- Measured harmonic intensity and spectral shifts varied with gas jet position.
- The numerical model demonstrated remarkable agreement with experimental harmonic spectra.
Conclusions:
- The study confirms the quasi-single-cycle excitation regime in neon gas jets with ultrashort laser pulses.
- The developed numerical model is a reliable tool for simulating and understanding HHG in this regime.
- Precise control over experimental parameters, like gas jet position, allows for tuning of harmonic emission properties.
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