NNSA PRISM Seminar Series: "Casimir Force and Near-field Radiative Heat Transfer....."
October 23 @ 3:00 PM - 4:00 PM - Birck 1001
Presented by: Joel Chevrier, Professor of Physics, University Joseph Fourier of Grenoble
Abstract: Near-field force and energy exchange between two objects due to quantum and thermal induced electrodynamic fluctuations give rise to interesting phenomena such as Casimir/van der Waals forces and thermal radiative transfer far exceeding Planck theory of blackbody radiation. While quantum fluctuations, related to zero point energy, yelds to the formulation of the Casimir/van der Waals force, near-field radiative heat transfer is only due to classical thermodynamics charge fluctuations. Although significant progress has been made in the past in the precise measurement of the Casimir force, a detailed quantitative comparison between theory and experiments in the sub-micron regime was still lacking when speaking about heat transfer. I shall first make a simple introduction on how the charge fluctuations give rises to these effects that are nowadays most effectively detected using MEMS or AFM technologies. This will lead me to question the relevance of these effects in the use of MEMS. After description of our quantitative measurement of the Casimir force and comparison with theory, I shall report on our experimental data on the thermal flux spatial dependence. Theory based on the Derjguin approximation, successfully used there for the first time to describe radiative heat transfer from the far field to the near field regimes, reproduces the measured dependence.
- Mari-Ellyn Brock