High intensity, laser solid interactions are capable of generating attosecond light bursts via high harmonic generation, most work focuses on single beam interactions. In this study, we perform a numerical investigation on the role of wavelength and polarization in relativistic, high harmonic generation from normal-incidence, two-beam interactions off plasma mirrors. We find that the two-beam harmonic generation mechanism is a robust process described by a set of well-defined selection rules. We demonstrate that the emitted harmonics from normal incidence interactions exhibit an intensity optimization when the incident fields are of equal intensity for two-color circularly-polarized fields.
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A multi-terawatt two-color beam for high-power field-controlled nonlinear optics
Two-color laser beams are instrumental in light-field control and enhancement of high-order harmonic, spectral supercontinuum, and terahertz radiation generated in gases, plasmas, and solids. We demonstrate a multi-terawatt two-color beam produced using a relativistic plasma mirror, with 110 mJ at 800 nm and 30 mJ at 400 nm. Both color components have high spatial quality and can be simultaneously focused, provided that the plasma mirror lies within a Rayleigh range of the driving fundamental beam. Favorable scaling of second-harmonic generation by plasma mirrors at relativistic intensities suggests them as an excellent tool for multi-color waveform synthesis beyond the petawatt level.
more » « less- Award ID(s):
- 1806911
- PAR ID:
- 10371627
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Letters
- Volume:
- 45
- Issue:
- 23
- ISSN:
- 0146-9592; OPLEDP
- Format(s):
- Medium: X Size: Article No. 6542
- Size(s):
- Article No. 6542
- Sponsoring Org:
- National Science Foundation
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