Ponderomotive self-focusing of a short laser pulse under a plasma density ramp

• Autorzy: Kant N. , Saralch S. , Singh H.
• Konferencja: 9th Kudowa Summer School „Towards Fusion Energy”
• Języki publikacji: EN

Abstrakty

EN

The ponderomotive self-focusing of a short laser pulse in an underdense plasma under a plasma density ramp is analyzed. The pulse may acquire a minimum spot size due to the ponderomotive self-focusing. Beyond the focus, the nonlinear refraction starts weakening, and the spot size of the laser pulse increases, resulting in an oscillatory self-focusing and defocusing behavior of the beam with the propagation distance. In order to minimize the defocusing, we introduce a localized upward plasma density ramp. Due to the upward plasma density ramp, the laser beam retains a minimum spot size. Self-focusing becomes stronger with a mild ripple as the propagation distance increases. The conditions for the ponderomotive self-focusing for suitable parameters of the laser beam and the plasma are determined. The plasma density ramp of the considered type may be observed in gas jet plasma experiments.

Słowa kluczowe

EN

self-focusing; underdense plasma; plasma density ramp; ponderomotive force; short laser pulse; Gaussian beam

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2011
• Tom: Vol. 56, No. 2
• Strony: 149--153
• Opis fizyczny: Bibliogr. 16 poz., rys.

Twórcy

autor

Kant N.

autor

Saralch S.

autor

Singh H.

• Department of Physics, Lovely Professional University, Phagwara-144402, Punjab, India, Tel.: [phone], Fax: [phone],

Bibliografia

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