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<p class="MsoPlainText">Next week’s colloquium will be by Pascal Del'Haye from the National Physical Laboratory. As usual, there will be tea/coffee afterwards in the common room.<o:p></o:p></p>
<p class="MsoPlainText"><o:p></o:p></p>
<p class="MsoPlainText">Title: Frequency Comb Generation and Spontaneous Symmetry Breaking in Microresonators<o:p></o:p></p>
<p class="MsoPlainText">Speaker: Pascal Del'Haye (NPL)<o:p></o:p></p>
<p class="MsoPlainText">Venue: John Anderson JA3.14<o:p></o:p></p>
<p class="MsoPlainText">Time/Date: 3pm Wed 2<sup>nd</sup> November 2016<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">Abstract:<o:p></o:p></p>
<p class="MsoPlainText">Microresonator-based frequency combs ("microcombs") have attracted a lot of attention for their potential applications in precision metrology, gas sensing, arbitrary optical waveform generation, telecommunication and integrated photonic
circuits. Microcombs are generated in ultra-high-Q optical resonators that enable the confinement of extremely high optical power levels in tiny mode-volumes. The high optical power densities lead to the conversion of a continuous wave laser into a comb of
equidistant optical modes that can be used like a ruler for optical frequency measurements. This talk presents new results in the field of microresonator-based frequency combs, which are a promising candidate to realize out-of-the-lab applications for this
technology.<o:p></o:p></p>
<p class="MsoNormal">The second part of the talk presents new results on optically induced symmetry breaking between counter-propagating light in microresonators. This effect shows that microresonators can act as nonreciprocal devices that transmit light in
one direction but not in the other. The symmetry breaking can be used for optical diodes, circulators and for the development of integrated optical gyroscopes.<o:p></o:p></p>
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