About once every hour, the high-powered laser would unleash one petawatt of energy (100 times the power delivered by the entire U.S. electrical grid) in a burst less than one trillionth of a second long, focused into a spot one tenth the diameter of a human hair, on a tiny metal foil target. The intensity was such that we would generate incredibly hot and incredibly dense plasmas—matter so hot it’s a gas of ions and free electrons - for the study of what we call high-energy density physics (HEDP).
Depending on the experiment, the precise heating and compression of the target sample could generate tiny explosions that replicate what happens inside supernovae. In some cases, the extreme crushing of material using enormous light pressure even resulted in entirely new states of matter, never before generated on earth, by completely rearranging the atomic and molecular structures.
That was 2006. Fast forward to 2020, and yes, the field of HEDP has evolved. Facilities have become more versatile, combining multiple lasers, or lasers with x-ray free electron lasers (XFELs), or with pulsed power machines. Experimentalists have developed a multitude of new measurement technologies, capable of greater accuracy at ultrashort time and length scales. All this new technology has led to enormous advances in HEDP, producing new knowledge relevant to planetary science, astrophysics, materials physics and fusion.