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Updated: Aug 18, 2026

NMR 15N Relaxation Experiments for the Investigation of Picosecond to Nanoseconds Structural Dynamics of Proteins
Published on: November 1, 2024
Roundabout relaxation: collective excitation requires a detour to equilibrium
Hidetoshi Morita1, Kunihiko Kaneko
1Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan. morita@complex.c.u-tokyo.ac.jp
Abstract:
Relaxation to equilibrium after strong and collective excitation is studied by using a Hamiltonian dynamical system of a one-dimensional XY model. After an excitation of a domain of K elements, the excitation is concentrated to fewer elements, which are made farther away from equilibrium, and the excitation intensity increases logarithmically with K. Equilibrium is reached only after taking this roundabout route, with the time for relaxation diverging asymptotically as Kgamma with gamma approximately 4.2.
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