Title: "Laboratory tests on dark energy"

The physical nature of the dark energy in the universe is completely unclear at the moment and many theoretical models co-exist. Nevertheless, if dark energy is due to vacuum fluctuations then there is a chance to probe some of its properties in laboratory experiments using superconducting devices. I will decribe a new model of dark energy where vacuum fluctuations of photons (or any other bosons) can switch from a gravitationally active phase (contributing to the cosmological constant Lambda) to a gravitationally inactive phase (not contributing to Lambda) via a Ginzburg-Landau-like phase transition [1]. This model allows for an interaction of dark energy with Cooper pairs in superconductors. I will describe new experiments with Josephson junctions and rotating superconductors that are currently being performed in this context. [1] C. Beck and M.C. Mackey, astro-ph/0703364, to appear in Int. J. Mod. Phys. D (2007)