Laser pulse compression technology invented in the late 1980s resulted in high-power, short-pulse laser techniques, enhancing laser intensity 10 million-fold in a quarter of a century.
Scientists at Osaka University discovered a novel particle acceleration mechanism they describe as a micro-bubble implosion, in which super-high energy hydrogen ions (relativistic protons) are emitted at the moment when bubbles shrink to atomic size through the irradiation of hydrides with micron-sized spherical bubbles by ultraintense laser pulses. Their research results were published in Scientific Reports.
The group led by Masakatsu Murakami has reported an astonishing physical phenomenon: When shrinking matter to unprecedented density, comparable toa mass the size of a sugar cube weighing more than 100 kilograms, high-energy protons are emitted from the positively-charged nanoscale clusters, a world first. Usually, an acceleration distance of several tens to hundreds of meters is necessary for conventional accelerators to generate such huge energy.