Efficient atomization of cesium metal in solid helium by low energy (10 $\mu$J) femtosecond pulses

Abstract

Metal atoms in solid and liquid helium-4 have attracted some interest either as a way to keep the atoms in a weakly perturbing matrix, or using them as a probe for the helium host medium. Laser sputtering with nanosecond pulsed lasers is the most often used method for atom production, resulting however in a substantial perturbation of the matrix. We show that a much weaker perturbation can be obtained by using femtosecond laser pulses with energy as low as 10 $\mu$J. As an unexpected benefit, the atomic density produced is much higher.