Supercontinuum emission from water using fs pulses in the external tight focusing limit

S. Sreeja; S. Venugopal Rao; P. Radhakrishnan; Surya P. Tewari; P. Prem Kiran

doi:10.1117/12.907278

30 January 2012 Supercontinuum emission from water using fs pulses in the external tight focusing limit

S. Sreeja, S. Venugopal Rao, P. Radhakrishnan, Surya P. Tewari, P. Prem Kiran

Proceedings Volume 8247, Frontiers in Ultrafast Optics: Biomedical, Scientific, and Industrial Applications XII; 824718 (2012) https://doi.org/10.1117/12.907278
Event: SPIE LASE, 2012, San Francisco, California, United States

Abstract

From the initial observation of self-channeling of high-peak power femtosecond (fs) laser pulses in air, propagation of intense ultrashort laser pulses in different media has become one of the most investigated research areas. The supercontinuum emission (SCE), a spectral manifestation of the spatio-temporal modifications experienced by a propagating ultrashort laser pulse in a nonlinear medium, has many practical applications. However, the extent of blue shift of SCE is reported to be constant due to the phenomenon of "intensity clamping". To further explore the recently observed regime of filamentation without intensity clamping, we measured the evolution of spectral blue shift of SCE resulting from the propagation of fs pulses (800 nm, 40 fs, 1 kHz) in distilled water under different focusing geometries. The efficiency of SCE from tight focusing (f/6) geometry was always higher than the loose focusing (f/12) geometry for both linear and circular polarized pulses. The blue edge of the SCE spectrum (λ_min) was found to be blue shifted for f/6 focusing conditions compared to f/12 focusing geometry. The lower bound of the intensity deposited in the medium measured from the self-emission from the filament demonstrated the existence of intensities ~ 6x10¹³ Wcm^-2, far beyond the clamping intensities achieved erstwhile.

Citation Download Citation

S. Sreeja, S. Venugopal Rao, P. Radhakrishnan, Surya P. Tewari, and P. Prem Kiran "Supercontinuum emission from water using fs pulses in the external tight focusing limit", Proc. SPIE 8247, Frontiers in Ultrafast Optics: Biomedical, Scientific, and Industrial Applications XII, 824718 (30 January 2012); https://doi.org/10.1117/12.907278

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available