Laser Interactions Create Powerful Magnetic Fields

Intense laser pulses, which possess strong magnetic and electric fields, can force the electrons in a plasma to oscillate dramatically. It is this unique interaction, which also produces very high current electron jets, that has fascinated scientists involved in a relatively new and risky area of fusion research.
At the Rutherford Appleton Laboratories in Oxfordshire, UK, scientists used the Vulcan Nd:glass laser aimed at plasma targets to produce intense magnetic fields of several million gauss.
The interaction between the pulse and preionized plasma produced an incident intensity of a few times 10¹⁸ W/cm². The resulting fields were substantially higher than those that were observed in earlier experiments at the Naval Research Laboratory in Washington. These results could be a step toward evaluating ultraintense laser applications such as those in laser fusion.
"This is very interesting for physics, but whether it can be used in fusion is something on the frontier," said John Stamper, a retired scientist at the Naval Research Laboratory who spent decades working on laser-plasma interactions.