Laser light forces and self-focusing in fully ionized plasmas

A derivation is given for the nonrelativistic equation of motion of a fully ionized isothermal plasma in the presence of an intense electromagnetic wave, such as laser light. The result can be expressed in a form similar to an equation used in the microwave confinement of plasmas. Applications of the result are made to the evaluation of self-focusing effects. The forces exerted on the plasma are found to be significant magnitude at contemporary intensity levels for neodymium laser radiation at λ = 1.06 μm.