Controlling real and virtual photons: from quantum forces to space propulsion

Condensed Matter Seminars

Speaker: Jeremy N. Munday, University of Maryland, College Park, MD
Date & Time: Thu, 2018-04-19 14:00 - 15:00
Location: BRIM 311
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Optoelectronic devices are used to detect and manipulate light for communications, sensing, solar power generation, etc. However, even in the dark (i.e. when no photons are present), there exist quantum fluctuations of electromagnetic fields (sometimes called virtual photons) that give rise to measurable effects. One such phenomenon is a force between two charge-neutral objects, known as the Casimir effect. Here, I will discuss our recent experiments that resulted in the first measurement of the Casimir force between two spheres. Next, I will describe an experiment aimed at detecting a Casimir torque, which was predicted to cause two objects to rotate in vacuum due to quantum fluctuations but has evaded detection for over 40 years. Finally, I will discuss the concept of a spacecraft powered by radiation pressure (resulting from momentum transfer upon photon reflection), and how optically switchable devices can enable actuation of such a craft. In addition to the fundamental science being pursued through this research, a number of interesting practical applications have been uncovered ranging from self-powered solar windows to novel optical and infrared detectors. I will conclude with a brief overview of these activities.