Image credit – Marija Vranic, Instituto Superior Técnico, University of Lisbon.
Figure SEQ Figure \* ARABIC 2: An optical trap for matter-antimatter plasma. The trap is formed by 4 lasers, arranged in one plane, all going towards the same point. When the lasers overlap, they form a 2D wave, with electric fields shown in the figure. There is a tiny object in the center, a nanowire 100x thinner than a human hair. The electrons are stripped off the wire and accelerated close to the speed of light. They are trapped in the wave, so when they lose most of their energy by emitting light, they get re-accelerated. The photons produce electron-positron pairs, themselves trapped. This process can create a dense electron-positron plasma that eventually converts most of the available laser energy into gamma-rays.