Office of Technology Transfer – University of Michigan

N2 Times Pulse Energy Enchancement Using Coherent Addition of N Orthogonally Phase Modulated Periodic Signals

Technology #5428

BACKGROUND

This invention provides with a new-frontier type of laser capability that currently does not exist: it enables lasers that simultaneously can produce very high pulse energy and very high average power. Current lasers can do either one of the two but none of the existing laser solutions can do both simultaneously. This solution is in general applicabe to any periodically-pulsed format, but it is expected that its greatest impact will be in the area of ultrashort-pulse lasers. We believe that it should enable compact TW - PW peak power lasers with multi-kW average power. It can be implemented with any type of laser gain medium, but should be especially useful when implemented with fiber laser technology. The idea exploits coherent beam combining of a laser array, but is based on an entirely new approach, which does not seem to be described in any prior art.

TECHNOLOGY

This is a completely new technical paradigm in that it uses coherent laser-beam combining not only to add-up laser power and energy “in parallel”, but also (this is the key unique aspect of the invention) interferes these combined signals in the time domain so that energy is re-distributed “longitudinally”. In essence it replaces the conventional laser scaling approcah where high power and enegy is extracted simply by using a larger crystal, with the new approach when instead of a laser crystal an “optical circuit” s used consisting of a number of integrated fiber-laser “boards”, and the generation of high pulse energies is achieved by synthesing a combined waveform (i.e. in effect “computing” this waveform).

APPLICATIONS

Application areas are very broad. First, since this can enable TW-PW peak power and multi-kW average power lasers, it should have a revolutionary impact on moving high-intensity laser-plasma accelerators from laboratory to wide-spread practical use. For example, this could enable portable and affordable high-brightness X-ray sources wih characteristics matching those of current Synchrotron sources (which are billion-$ scale facitlities), particle accelerators for material processing and medical applications, portable neutron, gamm and other particle sources for homeland security applications, etc. Second, high energy and high power nanosecond pulse sources could potentialy replace very large and expensive eximer lasers used in electronics industry. In the near term such lasers would have a large demand as scientific facilities.

ADVANTAGES

  • compact, portable, and efficienct practical high-energy lasers
  • achieving currently not available combination of high pulse energy and high average average power