High field applications (particles acceleration, laboratory-based astrophysics, fast ignitor fusion, generation of short pulse X-rays) benefit if laser repetition rate is increased
The first Petawatt laser (LLNL) had a repetition rate of 1 shot every few hours that was limited by poor thermal properties of disk amplifiers
Ti:sapphire CPA lasers have 2-fold advantage in regard to 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 same output power
Problem: glass laser has to be used to pump Ti:sapphire at100J energy but it still can be repetitive at this energy level because requirements for pump are less stringent