Tornoe, S. (ECE) – Improving the UV optical response and suppressing surface plasmon resonance in aluminum and silver base telescope mirrors

Aluminum and silver are excellent metal-bases for astronomical telescopes designed for broadband spectral measurements. In particular silver excels in the violet to infrared spectral range range with over 95% reflectance. In turn aluminum excels deep ultra-violet to infrared with over 90% reflectance across the bulk of its spectral range. In astronomical telescope optics, each percent reflectance is extremely valuable, meaning each mirror type has place. However, both metal-bases suffer from unwanted oxidation necessitating protective coatings. Unfortunately, even a few nanometers of traditional coatings like AlOx, can completely eliminate the far and deep UV response. These dielectric protective coatings can also induce surface plasmon resonance (SPR) in the mirrors. SPR occurs when light propagates in a dielectric protective coating along a metal-dielectric interface exciting electrons in the metal as it propagates. The plasmonic response in the metal-base alters how light reflects from the mirror creating an oscillation in the UV spectral range. This research will focus on improving the UV response and diminishing the detrimental effects of SPR for two cases: aluminum mirrors and silver mirrors.

Event Host: Soren Tornoe, Ph.D. Student, Electrical & Computer Engineering 

Advisor: Nobuhiko Kobayashi

Zoom: https://ucsc.zoom.us/j/93650451146?pwd=IFEbCOKZQAyDdoYMO5b19JqGZbX07m.1

Passcode: 657292