Influence of atomic density in high-order harmonic generation
(1996) In Optical Society of America. Journal B: Optical Physics 13(1). p.148-156- Abstract
- We have investigated how high-order harmonics generated in rare gases depend on the atomic density. The peak and the profile of the atomic density in the interaction region were measured as a function of the backing pressure and the distance from the nozzle by a differential interferometry technique, The conversion efficiency for the harmonics in the plateau was found to increase approximately quadratically over the entire range of peak pressures investigated (3-80 mbar). The intensity of the harmonics in the cutoff region, in contrast, increased only until an optimum peak pressure was reached, beyond which it decreased. This optimum peak pressure was found to be dependent on both the laser intensity and the process order. To understand... (More)
- We have investigated how high-order harmonics generated in rare gases depend on the atomic density. The peak and the profile of the atomic density in the interaction region were measured as a function of the backing pressure and the distance from the nozzle by a differential interferometry technique, The conversion efficiency for the harmonics in the plateau was found to increase approximately quadratically over the entire range of peak pressures investigated (3-80 mbar). The intensity of the harmonics in the cutoff region, in contrast, increased only until an optimum peak pressure was reached, beyond which it decreased. This optimum peak pressure was found to be dependent on both the laser intensity and the process order. To understand this effect, we have performed extensive propagation calculations of both the fundamental and the harmonic fields, using ionization rates and dipole moments from a tunnel ionization model. We obtained good agreement with the experimental results. The observed effect is attributed to ionization-induced defocusing of the fundamental laser beam, which reduces the peak intensity obtained in the medium and shortens the extent of the plateau. (C) 1996 Optical Society of America (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/2257190
- author
- Altucci, C ; Starczewski, Tomas ; Mevel, E ; Wahlström, Claes-Göran LU ; Carre, B and L'Huillier, Anne LU
- organization
- publishing date
- 1996
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Optical Society of America. Journal B: Optical Physics
- volume
- 13
- issue
- 1
- pages
- 148 - 156
- publisher
- Optical Society of America
- external identifiers
-
- scopus:0030532380
- ISSN
- 0740-3224
- DOI
- 10.1364/JOSAB.13.000148
- language
- English
- LU publication?
- yes
- id
- 9087fd23-3bba-4488-ab69-d0d7e0785429 (old id 2257190)
- date added to LUP
- 2016-04-04 09:43:05
- date last changed
- 2022-03-23 06:51:57
@article{9087fd23-3bba-4488-ab69-d0d7e0785429, abstract = {{We have investigated how high-order harmonics generated in rare gases depend on the atomic density. The peak and the profile of the atomic density in the interaction region were measured as a function of the backing pressure and the distance from the nozzle by a differential interferometry technique, The conversion efficiency for the harmonics in the plateau was found to increase approximately quadratically over the entire range of peak pressures investigated (3-80 mbar). The intensity of the harmonics in the cutoff region, in contrast, increased only until an optimum peak pressure was reached, beyond which it decreased. This optimum peak pressure was found to be dependent on both the laser intensity and the process order. To understand this effect, we have performed extensive propagation calculations of both the fundamental and the harmonic fields, using ionization rates and dipole moments from a tunnel ionization model. We obtained good agreement with the experimental results. The observed effect is attributed to ionization-induced defocusing of the fundamental laser beam, which reduces the peak intensity obtained in the medium and shortens the extent of the plateau. (C) 1996 Optical Society of America}}, author = {{Altucci, C and Starczewski, Tomas and Mevel, E and Wahlström, Claes-Göran and Carre, B and L'Huillier, Anne}}, issn = {{0740-3224}}, language = {{eng}}, number = {{1}}, pages = {{148--156}}, publisher = {{Optical Society of America}}, series = {{Optical Society of America. Journal B: Optical Physics}}, title = {{Influence of atomic density in high-order harmonic generation}}, url = {{https://lup.lub.lu.se/search/files/5398917/2296959.pdf}}, doi = {{10.1364/JOSAB.13.000148}}, volume = {{13}}, year = {{1996}}, }