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Electromagnetic Nanoscale Metrology Based on Entropy Production and Fluctuations



James R. Baker-Jarvis


Many electromagnetic measurements are based on the relationship between dissipation and fluctuations. As measurement frequencies increase and dimensional scales decrease, an understanding of fluctuations and the effects of nonequilbrium behavior become more important. In this paper we begin with deriving a new equation fro entropy rate in terms of correlation functions and apply this equation to dielectric and magnetic material measurements, cavity resonance, nose, and power. This exact equation is a very general fluctuation-dissipation relation between dissipation and the fluctuations of the reversible microscopic entropy. We show that many electromagnetic metrology areas can be formulated in terms of the entropy production. We apply this equation to study entropy fluctuation-dissipation equations for dielectric and magnetic susceptibilities, impedance and resonant systems, and Johnson-Nyquist noie. The approach used here is based on a derivation of an entropy evolution equation using an exact reversible Liouville-based statistical-mechanical theory. A variational principle is also derived for maximuym-entropy-production, that yields the linear equations for the polarization and magnetization reates and indicates the region of validity on Onsager's variational approach. Cavity resonance and relaxation loss peaks are related to maximum-entropy production.
Journal of Research (NIST JRES) -


dielectric, entropy, magnetic, maximum-entropy production, nonequilibrium, relaxation


Baker-Jarvis, J. (2008), Electromagnetic Nanoscale Metrology Based on Entropy Production and Fluctuations, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed May 24, 2024)


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Created October 8, 2008, Updated June 2, 2021