Editing Arago spot (section)

== Arago spot with matter waves ==

In 2009, the Arago spot experiment was demonstrated with a supersonic expansion beam of [[deuterium]] molecules (an example of neutral [[matter waves]]).<ref name="reisinger2009"/> Material particles behaving like waves is known from [[quantum mechanics]]. The wave nature of particles actually dates back to [[Louis de Broglie|de Broglie's]] hypothesis<ref name="debroglie"/> as well as [[Davisson–Germer experiment|Davisson and Germer's experiments]].<ref name="davisson"/> An Arago spot of electrons, which also constitute matter waves, can be observed in [[transmission electron microscope]]s when examining circular structures of a certain size.

The observation of an Arago spot with large molecules, thus proving their wave-nature, is a topic of current research.<ref name="reisinger2009"/>