Bright Ideas
Dr Jennifer Hastie leads research into new kinds of
semiconductor laser that have not been built before.
These lasers are easily tuneable, even at visible and
ultraviolet wavelengths, which make them highly
applicable in many fields – especially Biophotonics.
Research area
Dr Jennifer Hastie is a Research Team
Leader at the Instit ute of Photonics,
Strathclyde University. Her research
work has focused on the development
of optically pumped (using light as the
‘fuel’) semiconductor disk lasers (SDLs)
that use novel semiconductor materials
and nonlinear conversion techniques.
This enables the lasers to operate
at novel wavelengths. Conventional
semiconductor lasers are electrically
injected, and the advantage of optically
pumped devices is that they offer
high beam quality with relatively high
output power, and this improves the
brightness of the laser significantly.
Dr Hastie’s work on this type of laser
began with her PhD thesis when she
worked on solving an issue that held
back the development of these lasers:
managing the heat they generate when
in operation. “We optimised the heat
removal using transparent materials
with exceptional thermal conductivity,
such as silicon carbide and diamond,
and could demonstrate higher power
for these lasers at any SDL emission
wavelength,” she said.
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With the practicality demonstrated,
Dr Hastie’s work during the period
of her Royal Academy of Engineering
Fellowship was directed towards
expanding the spectral range of these
devices. Dr Hastie said, “Previous SDLs
operated in the invisible infrared range,
but we saw an opportunity to target
our work towards the applicationsrich areas of visible and ultraviolet
where it is much more difficult to get
conventional compact laser sources.
“The principal advantage of these
lasers is our ability to tailor the
wavelength to meet different
application needs – they are more
easily engineered than others”.
The work involved designing the
semiconductor structure that provides
the amplification at the desired
wavelength within the laser, sometimes
using novel materials, then working
with external fabrication specialists
to produce the structure, followed by
further refinement and performance
testing.
Dr Hastie’s research during her
Academy Fellowship was further
supported by project funding from
EPSRC. This supported her work on
ultraviolet SDLs for use in biophotonics
and on indium phosphide quantum dot
SDLs. The second of these projects
was in collaboration with researchers
at Cardiff and Sheffield
Universities.
Key achievements
Dr Hastie is a senior member
of international optical and
engineering societies and sits on the
technical programme committees of
leading conferences and meetings
on lasers. In 2011, she was appointed
a member of the Royal Society of
Edinburgh’s Young Academy of
Scotland.