Spontaneous bursts of light,
which last trillionths of a second, change color as they pulse from within a solid-state block
and illuminate the unusual way interacting quantum particles behave when they are driven far from equilibrium. A way to trigger these flashes may lead to new telecommunications equipment and other devices that transmit signals at picosecond speeds.
The Rice University lab of Junichiro Kono said the phenomenon can be understood as a combination of two previously known many-body concepts: superfluorescence, as seen in atomic and molecular systems, and Fermi-edge singularities, a process known to occur in metals.