Open AccessCalibration of a high harmonic spectrometer by laser induced plasma emission
Author(s) -
Joseph Farrell,
B. K. McFarland,
P. H. Bucksbaum,
Markus Gühr
Publication year - 2009
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.17.015134
Subject(s) - optics , high harmonic generation , laser , harmonics , spectrometer , harmonic spectrum , extreme ultraviolet , physics , harmonic , calibration , emission spectrum , spectral line , plasma , wavelength , focus (optics) , voltage , quantum mechanics , astronomy
We present a method that allows for a convenient switching between high harmonic generation (HHG) and accurate calibration of the vacuum ultraviolet (VUV) spectrometer used to analyze the harmonic spectrum. The accurate calibration of HHG spectra is becoming increasingly important for the determination of electronic structures. The wavelength of the laser harmonics themselves depend on the details of the harmonic geometry and phase matching, making them unsuitable for calibration purposes. In our calibration mode, the target resides directly at the focus of the laser, thereby enhancing plasma emission and suppressing harmonic generation. In HHG mode, the source medium resides in front or after the focus, showing enhanced HHG and no plasma emission lines. We analyze the plasma emission and use it for a direct calibration of our HHG spectra.