Abstract

Lasers of Petawatt power have numerous applications, such as particles acceleration, laboratory-based astrophysics, fast ignitor fusion, generation of short pulse X-rays [1]. All these application would greatly benefit if laser repetition rate is increased. The first Petawatt laser [2] was based on 30 cm diameter Nd:glass disk amplifier and had a repetition rate of 1 shot every few hours that was limited by poor thermal properties of disk amplifiers . Ti:sapphire-based CPA lasers have 2-fold advantage over their Nd:glass based counterparts in regards to their repetition rate. Firstly, sapphire has much better thermal properties and secondly, the size of the amplifier is smaller because about an order of magnitude less energy is needed for Ti:sapphire laser to produce the s ame output power. Power up to 100 TW at 10 Hz has been demonstrated [2] using Ti:sapphire amplifier pumped with frequency doubled Nd:YAG lasers. As output energy of Nd:YAG laser is significantly below a value ( 60-80 J) required for pumping Petawatt scale Ti:sapphire lasers, glass pump lasers are used limiting repetition rate to a single shot operation [3]

© 2003 Optical Society of America