Results of Measuring the Influence of Casimir Energy on Superconducting Phase Transitions

• Published in: Journal of superconductivity and novel magnetism 2012-12, Vol.25 (8), p.2557-2565
• Main Authors: Allocca, Annalisa, Bimonte, Giuseppe, Born, Detlef, Calloni, Enrico, Esposito, Giampiero, Huebner, Uwe, Il’ichev, Evgeni, Rosa, Luigi, Tafuri, Francesco
• Format: Article
• Language: English
• Subjects: Aluminum; Bcs theory and its development; Characterization and Evaluation of Materials; Condensed Matter Physics; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Deviation; Dispersions; Exact sciences and technology; Holes; Letter; Magnetic fields; Magnetic Materials; Magnetism; Metals, alloys and compounds (a15, 001c15, laves phases, chevrel phases, borocarbides, etc.); Phase transformations; Physics; Physics and Astronomy; Strongly Correlated Systems; Superconducting films and low-dimensional structures; Superconducting materials (excluding high-tc compounds); Superconductivity; Theory and models of superconducting state
• ISSN: 1557-1939; 1557-1947
• DOI: 10.1007/s10948-012-1767-y

The ALADIN experiment aims at observing how the critical magnetic field of a superconducting aluminum film is modified, when it constitutes one of the reflecting surfaces of a Casimir cavity. If successful, such an observation would reveal the influence of vacuum energy on the superconducting phase transition. In this paper, a rigorous analysis of experimental data is reported, the results are discussed and compared with theoretical predictions based on Lifshitz theory of dispersion forces, and the BCS formula for the optical conductivity of superconductors. Thanks to this rigorous analysis, it can now be asserted that in the region of energy where it is expected that Casimir energy is comparable with condensation energy and the deviations of critical field from BCS formula to be not negligible, an anomalous behavior is found.