UCD Physics - RDS

Distinguished Speaker Series 2012

See below to book your tickets

When the first laser was demonstrated in 1960, it was recognized as a most remarkable light source because of the impressive features of high intensity, excellent phase coherence with spectral purity and beam directionality that were offered.   However, just a few years later, another quite distinctive strand of laser development began.  This showed that instead of the light emerging from the laser as a constant intensity beam, the light could be extracted in the form of a periodic sequence of discrete and extremely intense optical pulses. In fact, modern lasers now produce periodic sequences of femtosecond [1fs =10-15s] pulses that can be amplified to enormously high peak powers in the petaWatt range (where 1PW=1015 W) and, when desired, there is an option for the subsequent generation of even shorter, attosecond (1as=10-18s), pulses in the soft X-ray region of the electromagnetic spectrum!

The science that has underpinned the key developments of ultrafast lasers during the past five decades is an interesting story in itself and some of the highlight achievements will be reviewed briefly in my presentation.  In particular, I will mention how the design considerations relating to a 1980s style femtosecond laser led researchers to devise much more practical and compact 21st century counterparts.  It is probably also worth mentioning that in this 20-year period the efficiency of ultrafast lasers had been increased by a factor of almost one million!

Complementarily, the many and varied implementations that demonstrate the versatility and applicability of ultrashort-pulse lasers can serve to convey the clear message that the translation of the research-based systems to technologically compatible and practical products is becoming well established.   Within this context, and by way of examplars, I will describe some applications that range from novel optical imaging through material processing to cell biology.  The illustrations opposite and below show that light pulses can be used in corneal surgery for visual correction, or alternatively, to puncture cell membranes to produce a transient pore (poration) through which biologically active material such as DNA or RNA may be injected (transfection).

More information on Prof. Wilson Sibbett can be found at: http://www.laserfest.org/lasers/pioneers/sibbett.cfm

For more information contact us at: physics@ucd.ie