Cosmos:
"'Squeezing' laser light could significantly improve the
accuracy of detectors searching for Einstein's elusive
gravitational waves," writes Myles Gough for
Cosmos magazine. Because gravitational waves, which
are generated by violent astronomical events, have traveled
billions of light-years before reaching Earth, they are greatly
weakened and thus difficult to detect. Until now, the accuracy
of the laser interferometers used to detect the waves has been
limited by a quantum phenomenon of light called "shot
noise"—a type of electronic interference. To overcome
this problem, Roman Schnabel of the Max Planck Institute for
Gravitational Physics in Germany and coworkers perfected a
method of "squeezing" the light to reduce the noise to less
than that dictated by the Heisenberg uncertainty principle and
then feeding the squeezed light into the interferometer, along
with the normal laser light, which resulted in a laser beam
with a much more uniform intensity. "One can say that for the
first time a 'technology' is based on one of the distinct
features of quantum physics itself. We were able to leave the
stage of laboratory experiments and realize a real
application," said Schnabel. The group's
results,
published in
Nature Physics, are an exciting step forward for the
Laser Interferometry Gravitational-Wave Observatory (LIGO)
project in its quest to observe gravitational waves using
Earth-based detectors.
