LIP Lisboa

The 2018 Nobel Prize in Physics

by Prof. José Manuel Rebordão (FCUL)

Europe/Lisbon
311 (LIP seminar room)

311

LIP seminar room

Description

"... for groundbreaking inventions in the field of laser physics".

The inventions being honoured this year have revolutionised laser
physics. Extremely small objects and incredibly rapid processes are now
being seen in a new light. Advanced precision instruments are opening up
unexplored areas of research and a multitude of industrial and medical
applications.

ARTHUR ASHKIN invented optical tweezers that grab particles, atoms,
viruses and other living cells with their laser beam fingers. This new
tool allowed Ashkin to realise an old dream of science fiction - using
the radiation pressure of light to move physical objects. He succeeded
in getting laser light to push small particles towards the centre of the
beam and to hold them there. Optical tweezers had been invented. A major
breakthrough came in 1987, when Ashkin used the tweezers to capture
living bacteria without harming them. He immediately began studying
biological systems and optical tweezers are now widely used to
investigate the machinery of life.

GÉRARD MOUROU and DONNA STRICKLAND paved the way towards the shortest
and most intense laser pulses ever created by mankind. Their
revolutionary article was published in 1985 and was the foundation of
Strickland's doctoral thesis. Using an ingenious approach, they
succeeded in creating ultrashort high-intensity laser pulses without
destroying the amplifying material. First they stretched the laser
pulses in time to reduce their peak power, then amplified them, and
finally compressed them. If a pulse is compressed in time and becomes
shorter, then more light is packed together in the same tiny space - the
intensity of the pulse increases dramatically. Strickland and Mourou's
newly invented technique, called chirped pulse amplification, CPA, soon
became standard for subsequent high-intensity lasers. Its uses include
the millions of corrective eye surgeries that are conducted every year
using the sharpest of laser beams.

FROM THE PRESS RELEASE