Masahiro Ono, NASA JPL – Comet Hitchhiker: Harvesting Kinetic Energy from Small Bodies to Enable Fast and Low-Cost Deep Space Exploration in the first half of a video below.
Nextbigfuture focused on the second half with the talk by Young Bae.
Young Bae, Y.K. Bae Corporation – Propellant-less Spacecraft Formation-Flying and Maneuvering with Photonic Laser Thrusters
Young Bae used a diamond thin disk laser and increased the power to achieve 1.03 millinewtons of force with a laser photonic thruster.
It bounces lasers between mirrors. The bouncing amplification was 100-200 times.
He believes they can get bouncing amplification to 1000 times.
The mirrors can handle 50 megawatts per square centimeter and they are at 500 kilowatts per square centimeter.