Measurement of 3/2-harmonic radiation in high-intensity femtosecond laser-solid interaction

摘要

Summary form only given. We report to our knowledge the first experiments and pulse duration dependence of high intensity fs-laser generated 3/2-harmonic radiation in inhomogeneous plasmas and the comparison of this effect to theory. p-polarized 150 fs, 790 nm Ti:sapphire laser pulses with an energy of 200 mJ were focused under an angle of incidence of 45/spl deg/ to an intensity of 2 /spl times/ 10/sup 17/ W/cm/sup 2/ onto a polished aluminum target inside a vacuum chamber. The generated 3/2-radiation was collimated in the specular direction.