2018/07/19 by G. L. Klimchitskaya, G. L . Klimchitskaya, V. M. Mostepanenko · 1 citation
Engineering · Physics and Astronomy · #Casimir effect #Engineering physics #Graphene #Indium #Indium tin oxide #Materials science #Mechanical and Optical Resonators #Metallurgy #Nanotechnology #Optoelectronics #Oxide #Physics #Quantum Electrodynamics and Casimir Effect #Quantum mechanics #Thermal Radiation and Cooling Technologies #Thin film #Tin #cond-mat.mtrl-sci #cond-mat.other
paper · pdf · doi:10.1103/physrevb.98.035307
published as Phys. Rev. B v.98, 035307 (2018) · 18 pages, 6 figures; accepted for publication in Phys. Rev. B
arxiv created 2018/07/19 · openalex publication_date 2018/07/30 · arxiv updated 2018/08/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We reconsider the long-explored problem that the magnitude of the measured Casimir force between an Au sphere and an indium tin oxide (ITO) film decreases significantly after the UV treatment with no respective changes in the ITO dielectric permittivity required by the Lifshitz theory. Two plausible resolutions of this conundrum are discussed: the phase transition of an ITO film from metallic to dielectric state and the modification of a film surface under the action of UV light. To exclude the latter option, we propose an improvement in the experimental scheme by adding a graphene sheet on top of an ITO film. The formalism is developed allowing precise calculation of the Casimir force between an Au sphere and a graphene sheet on top of ITO film deposited on a quartz substrate. In doing so Au, ITO, and quartz are described by the frequency-dependent dielectric permittivities and real graphene sheet with nonzero mass-gap parameter and chemical potential by the polarization tensor at nonzero temperature. Numerical computations performed both before and after the phase transition resulting from the UV treatment show that the presence of graphene leads to only a minor decrease in the drop of the Casimir force which remains quite measurable. At the same time, in the presence of graphene the guess that an observed drop originates from the modification of an ITO surface by the UV light breaks down. Similar results are obtained for the configuration of two parallel plates consisting of a graphene sheet, an ITO film, and a quartz substrate. The proposed experiments involving additional graphene sheets may help in resolution of the problems arising in application of the Lifshitz theory to real materials.