LONGITUDINAL MODES IN A HIGH‐GAIN LASER

Competition and bistability of longitudinal modes in a Raman laser.

The Raman laser is an optically pumped three-level laser in which both the pump and the laser field ~frequencies vP and vL , respectively! are far off resonance ~see Fig. 1!. This system is commonly used to produce high gain steady-state lasing emissions in the midto far infrared spectral region @1#. In addition, this system can show a very rich dynamical behavior @2#, including single-mode pul...

Improving the stability of longitudinal and transverse laser modes

We show that laser mode stability can be improved with an intracavity mode selecting phase element. Without the phase element, a sub-wavelength change of the distance between the mirrors of a CO2 laser leads to a substantial change of the transverse mode distribution, whereas with it the distribution remains essentially the same. 2004 Elsevier B.V. All rights reserved. PACS: 42.60.Lh; 42.60.Jf;...

Longitudinal Laser Shaping in Laser Wakefield Accelerators

A digital laser for on-demand laser modes.

Customizing the output beam shape from a laser invariably involves specialized optical elements in the form of apertures, diffractive optics and free-form mirrors. Such optics require considerable design and fabrication effort and suffer from the further disadvantage of being immutably connected to the selection of a particular spatial mode. Here we overcome these limitations with the first dig...

Gaussian modes in high loss laser resonators.

Matrix techniques are applied to the mode analysis of laser resonators having spherical mirrors and Gaussian profiles of the mirror reflectivity. These same analytical methods provide a useful approximation to the mode and loss characteristics of conventional resonators having an abrupt discontinuity of the reflectivity. Mode selection in apertured waveguides and resonators is also discussed.