The existence of planets outside our solar system was first confirmed in 1995. The discovery was embraced by the scientific community and the public, since it made the possibility of extraterrestrial life more real. Since then, over 100 systems have been found, some with multiple planets. To date, astronomers have found these celestial bodies using only indirect methods: changes in radial velocity, gravitational wobbling, microlensing, brightness changes due to a transit. An extrasolar planet has not yet been directly imaged; this is exceedingly difficult since the planet is very close to its sun from our point of view and is millions of times dimmer. Several methods have been proposed to attenuate the blinding glare of the star. One of these is an interferometric technique in which the relatively intense starlight would be hidden inside of an optical vortex created by a transmission phase mask [Grover A. Swartzlander, Jr., Optics Letters 26, 497 (2001)].

The goal of our project is to simulate and test Swartzlander's proposed method in small-scale laboratory experiments. We will initially create an optical vortex with laser light and a computer-generated hologram. The next step will be to replace the laser with a quasi-monochromatic and spatially-coherent source such as a pinhole or optical fiber illuminated by filtered white light from a halogen lamp. A second pinhole or optical fiber could then be used to simulate the faint light of the nearby planet.

We would like to thank Grover Swartzlander, Jr. (University of Arizona, Tucson) for invaluable suggestions, and Prof. E. Galvez (Colgate University) for providing the computer-generated hologram.

Azure Hansen March 2004

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