Demonstration of a plasma mirror based on a laminar flow water film

A plasma mirror based on a laminar water film with low flow speed (0.5–2 cm/s) has been developed and characterized, for use as an ultrahigh intensity optical reflector. The use of flowing water as a target surface automatically results in each laser pulse seeing a new interaction surface and avoids the need for mechanical scanning of the target surface. In addition, the breakdown of water does not produce contaminating debris that can be deleterious to vacuum chamber conditions and optics, such as is the case when using conventional solid targets. The mirror exhibits 70% reflectivity, while maintaining high-quality of the reflected spot.