<title>Measurements of profile of energy density and wavefront of pulsed laser beam propagating through near-resonant medium</title>

Abstract

We measured the energy density profile and wavefront of the laser beam through the near resonator sodium heat pipe using a linear sensor camera and a Shack-Hartmann type wavefront sensor. Development of the wavefront was obtained as a function of laser wavelength, and self-focusing and -defocusing were observed for a small laser beam diameter. The energy density profile of the laser beam shows good agreement with the result of our simulation code based on the coupled Maxwell-Density Matrix equations including transverse and time- dependent variations. For the laser beam with large diameter, change of wavefront from the convex to the concave in the shorter wavelength region was observed.