  We examine the properties of a gaseous plasma resonator generated by focusing
a high-energy laser pulse through a lens and into a gas. An analytical model is
presented describing the scattering resonance of these near-ellipsoidal plasmas
and its dependence on their eccentricity and intrinsic plasma properties. This
dependence is investigated through Ku band transmission experiments of a
waveguide with an embedded single plasma element and through optical
diagnostics of the laser-induced plasma. The described resonator has the
potential to be used as the building block in a new class of metamaterials with
fully three-dimensional structural flexibility.
