2007/09/05 by D. A. Garanin
Chemistry · Materials Science · Physics and Astronomy · #Advanced NMR Techniques and Applications #Bottleneck #Condensed matter physics #Excitation #Laser linewidth #Magnetism in coordination complexes #Phonon #Physics #Quantum and electron transport phenomena #Quantum mechanics #Relaxation (psychology) #Spin (aerodynamics) #Spins #cond-mat.mtrl-sci #cond-mat.stat-mech
paper · pdf · doi:10.1103/physrevb.77.024429
published as Phys. Rev. B 77, 024429 -(16) (2008) · 16 PR pages, 14 Figure captions, submitted to PRB. The whole text does dot fit here. Please, get the correct file from http://www.lehman.edu/faculty/dgaranin/Bottleneck2.pdf
arxiv created 2007/09/05 · openalex publication_date 2008/01/31 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The phonon-bottleneck problem in the relaxation of two-level systems (spins) via direct phonon processes is considered numerically in the weak-excitation limit where the Schr"odinger equation for the spin-phonon system simplifies. The solution for the relaxing spin excitation p(t), emitted phonons nk(t), etc., is obtained in terms of the exact many-body eigenstates. In the absence of phonon damping \ensuremathΓph and inhomogeneous broadening, p(t) approaches the bottleneck plateau p_\ensuremath∞>0 with strongly damped oscillations, the frequency being related to the spin-phonon splitting \ensuremathΔ at the avoided crossing. For any \ensuremathΓph>0, one has p(t)\ensuremath→0, but in the case of strong bottleneck, the spin relaxation rate is much smaller than \ensuremathΓph and p(t) is nonexponential. Inhomogeneous broadening exceeding \ensuremathΔ partially alleviates the bottleneck and removes oscillations of p(t). The linewidth of emitted phonons as well as \ensuremathΔ increase with the strength of the bottleneck, i.e., with the concentration of spins.