Low temperature ESR in spin ladder (C7H10N)2Cu(1-x)ZnxBr4
Spin-gap magnet (C7H10N)2Cu(1-x)ZnxBr4 (DIMPY) is an example of a strongleg
spin ladder. We report here the results of the ESR study of pure and diamagnetically diluted
DIMPY. ESR study of the pure system (x=0) revealed that the spin dynamics of DIMPY is
a ected by uniform Dzyaloshinskii-Moriya (DM) interaction. We observe narrowing of the ESR
absorption line in diamagnetically diluted DIMPY pointing to suppression of DM channel of
spin relaxation by doping.
We report low temperature electron spin resonance experimental and theoretical studies of an archetype S=1/2 strong-rung spin ladder material (C5H12N)2CuBr4. Unexpected dynamics is detected deep in the Tomonaga-Luttinger spin liquid regime. Close to the point where the system is half-magnetized (and believed to be equivalent to a gapless easy plane chain in zero field) we observed orientation-dependent spin gap and anomalous g-factor values. Field theoretical analysis demonstrates that the observed low-energy excitation modes in magnetized (C5H12N)2CuBr4 are solitonic excitations caused by Dzyaloshinskii-Moriya interaction presence.
We have studied electron spin resonance (ESR) absorption spectra for the nonmagnetically diluted strong-leg spin ladder magnet (C7H10N)2Cu(1−x)ZnxBr4 (abbreviated as DIMPY) down to 450 mK. Formation of the clusters with nonzero net magnetization is confirmed; the cluster-cluster interaction is evidenced by the concentration dependence of ESR absorption. High-temperature spin-relaxation time was found to increase with nonmagnetic dilution. The ESR linewidth analysis proves that the Dzyaloshinskii-Moriya (DM) interaction remains the dominant spin-relaxation channel in diluted DIMPY. Experimental data indicate that the dilution results in the weakening of the effective DM interaction, which can be interpreted as total suppression of DM interaction in the close vicinity of impurity atom.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.