Practical fusion?: A new ultrafast laser offers hope
Nuclear fusion promises clean, unlimited energy, of the sort created by the sun. But making a practical reactor is difficult and expensive. In one approach, called inertial fusion, scientists bombard a tiny pellet of deuterium-tritium fuel with intense laser pulses to kick off the fusion reaction.
The problem, said Princeton mechanical engineering professor Szymon Suckewer, is that this technique requires large lasers that come with equally large price tags—billions of dollars. One leading idea to make fusion more efficient is a two-laser system that ignites the fuel pellet in steps. Suckewer is developing an extremely powerful, compact laser that could greatly reduce the cost of the first step.
His laser exploits the properties of plasmas -- hot ionized particles -- to transfer energy from one laser into another, producing pulses that deliver an enormous amount of power (on the order of petawatts, or 1015 watts) in ultrashort bursts measured in femtoseconds. In addition to reducing the cost of fusion, the new laser could lead to a practical x-ray laser, a long-sought tool for microscopy and for manufacturing ultra-small devices, including computer chips.