Eleana Makri, a PhD candidate in physics, spoke on “Reflective Photonic Limiters: a Novel Scheme for Sensor Protection” during the Graduate Student Speaker Series Feb. 10 in Exley Science Center. Photonic limiters are devices designed to transmit low-level radiation, while blocking electromagnetic pulses of power or total energy exceeding a certain threshold.
Since the first lasers were developed in the 1960’s, there has been an interest in building non-mechanical photonic limiters, which can be used to protect optical sensors (for example, the human eye) against laser-induced damage. “The basic principle of operation of these devices is to exploit several absorption mechanisms of their constituent materials in order to block excessive radiation,” she said. “The main drawback of this method is that absorption can lead to overheating, eventually causing the destruction of the limiter.” Makri introduced the audience to to reflective photonic limiters, which are designs that become reflective instead of absorptive at high-level radiation. “Consequently, they can offer protection to optical sensors while avoiding their self-destruction,” she explained.
Makri’s advisor is Tsampikos Kottos, professor of physics, professor of integrative sciences. The next speaker in the Graduate Student Speaker Series is Stephen Frayne, a PhD candidate in chemistry. He will speak at noon, April 20 in Exley Room 58.
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