Enhancement of filamentation postcompression by astigmatic focusing

The energy scaling up of pulse postcompression is still an open issue. In this work we analyze the use of astigmatic focusing to improve the output pulses in a filamentation based postcompression setup. Unlike spherical conditions, astigmatic focusing enhances the output energy and the spectral broadening of the filament. This is due to the increase of critical power, allowing a considerable improvement of the postcompression energy and stability in a simple way. We demonstrated compression from FWHM 100 fs, 10 nm, 3 mJ input pulses to 13 fs, 142 nm, near 1 mJ pulses.We acknowledge support from the Spanish Ministerio de Ciencia e Innovación through the Consolider Program SAUUL (CSD2007-00013), Research project FIS2009- 09522, and grant programs Formación de Profesorado Universitario (for B. Alonso and R. Borrego-Varillas) and Ramón y Cajal (for I. J. Sola), and from the Junta de Castilla y León through the Program for Groups of Excellence (GR27). We also acknowledge support from the Centro de Láseres Pulsados, Salamanca, Spain

Design and calibration of an Radiation Thermometer

6 páginas, 5 figuras, 2 tablas.-- Trabajo presentado a la VII Reunión Española de Optoelectrónica celebrada del 29 de Junio al 1 de Julio de 2011 en Santander.[EN]: Following other national metrological laboratories, as NIST, PTB or NPL, our laboratory is developing, in collaboration with the CEM, a low uncertainty filter radiometer. The device is based on radiance measurement with a filter detector and a lens system. In this paper we present the realized works in this way, with some measures promising for our objective.[ES]: Siguiendo la estrategia de Laboratorios Nacionales de metrología de alto nivel metrológico como son el NIST, PTB o NPL, nuestro laboratorio está desarrollando en colaboración con el CEM un radiómetro de filtro para medidas de alta temperatura con baja incertidumbre. El instrumento se basa en la medida de la radiancia con un detector, un filtro interferencial y un sistema de lentes. En el artículo se presentan los trabajos realizados en esta dirección, con medidas prometedoras para su desarrollo.Convenio especifico CSIC-CEM para la medida de la temperatura con métodos radiométricos.Peer reviewe

Compensation of second-order dispersion in femtosecond pulses after filamentation using volume holographic transmission gratings recorded in dichromated gelatin

We have designed and developed a pulse compressor with volume transmission holographic gratings to be implemented in post-compression experiments based on filamentation in gases. Pulse compression down to 13 fs has been demonstrated. The gratings have been recorded in commercial PFG-04 dichromated gelatin emulsions with a recording wavelength of 532 nm, attaining sufficient index modulation to achieve high efficiency when they are illuminated by an 800-nm laser.This research has been supported by the Diputación General de Aragón (Grupo Consolidado TOL), the Universidad de Zaragoza (under grant UZ2010-CIE-02), the Spanish Ministerio de Ciencia y Tecnología (FEDER funds, grant FIS2006-04151) and grant Consolider Programme SAUUL (CSD2007-00013)), COST (grant CM0702-CUSPFEL), and the Junta de Castilla y León (grants GR27 and SA002B08). We also acknowledge support from the Centro de Laseres Pulsados, CLPU, Salamanca, Spain. B. Alonso and I.J. Sola acknowledge support from the Spanish Ministerio de Ciencia e Innovación through the ‘Formación de Profesorado Universitario’ and ‘Ramón y Cajal’ grant programs, respectively. Valuable assistance by J. Rodríguez Vázquez de Aldana and R. Torres is also acknowledged