M Squared Lasers announces new compact, widely tunable terahertz source
Firefly-THz is based on novel, highly
efficient intra-cavity optical parametric oscillator (OPO)
technology developed by the University of St. Andrews, UK. Output
powers >10µW at 400Hz (10x higher power than equivalent THz
sources) have already been demonstrated, with continuous tuning
from 1 to >3.5THz (<100 to 250µm). Higher powers and wider
tuning are also expected.
Dr Graeme Malcolm, CEO of M Squared Lasers, commented 'We are
delighted to have the opportunity to commercialize the St. Andrew's
THz technology exclusively. The unique properties of THz waves hold
great promise for many detection, imaging, non-destructive testing
and security applications. The lack of truly practical,
cost-effective THz sources to date, however, has inhibited the
widespread realization of THz applications. Firefly-THz,
however, represents a new, efficient and cheaper approach to THz
sources.
Dr Gareth Maker, head of R&D at M Squared Lasers, explained
how applications would benefit from the Firefly-THz design.
'Firefly-THz offers several advantages over other methods of
generating THz radiation. Unlike far infrared molecular lasers, or
optical rectification/ optically induced photoconductive switching
with relatively costly femtosecond lasers, Firefly-THz provides
wide and continuous tuning. This allows users to cover the THz
absorption features or 'fingerprints' of many different substances
with a single device. And unlike THz systems excited by femtosecond
pulses, Firefly-THz operates in the frequency (spectral) domain
rather than time domain. This removes the need for post-detection
Fourier transform data processing and averaging. Quantum cascade
lasers are also being explored as sources of THz radiation, but
they generally need cryogenic cooling - a major drawback for
practical THz devices. Firefly-THz also provides improved output
power compared to devices using difference frequency mixing, and
unlike quantum cascade lasers and femtosecond laser excitation
schemes, its beam quality is close to
diffraction-limited.'