Previous experiments were done with laser pulses that lasted more than 400 quadrillionths
of a second, or approximately 10 times longer than the ultrashort pulses.
The just-patented system under development at the University of Sherbrooke in Canada delivers 1,000 pulses of infrared light per second, each lasting only about 100 quadrillionths
of a second, says laser physicist and study coauthor Daniel Houde.
These conducting nanoscale dielectric slivers are what Hunt calls liquid glass electrodes, fabricated at the U-M Center for Ultrafast Optical Science with a femtosecond laser, which emits light pulses that are only quadrillionths
of a second long.
The NIF laser packs more energy overall, but since peak power is a function of both average power and pulse length, BELLA took the crown with shorter pulses lasting just 40 quadrillionths
of a second.
The laser emits 10 billion pulses per second, with each pulse lasting about 40 femtoseconds, or quadrillionths
of a second, producing extra-wide spacing between individual comb teeth.
Since the laser pulses last only a matter of picoseconds, or quadrillionths
of a second, they do not cause heat damage to the foil-thin stainless steel and titanium material used to make the stents.