Magnetic correlations

Self-assembly and self-organization may result in a range of collective properties such as, in addition to phase changes already mentioned, directed light propagation, electronic conduction, magnetism, correlated protonic motions, etc. 

G. Aeppli and C. Broholm, Magnetic correlations in heavy-fermion systems neutron scattering from single crystals 123... 

Short Range Order (SRO) and Low-dimensional Magnetic Correlations... 

In principle, one wonld expect ID magnetic correlations to dominate bnt the interchain separation is not sufficiently great... 

Figure 60 Short range magnetic correlations in Tb2Ti207 at various temperatures up to 50 K. The x-axis is Q = 4jr sm0/X. (Reprinted with permission from J.S. Gardner, S.R. Dimsiger, B.D. Gaulin, M.J.P. Gingras, J.E. Greedan, R.F. Kiefl, M.D. Lmnsden, W.A. MacFarlane, N.P. Raju, J.E. Sonier, I. Swainson, Z. Tun, Phys.Rev.Lett, 1999, 82, 1012. 1999 by the American Physical Society)...

Magnetic correlations are caused by magnetic interactions. The interacting system has a ground state and excited states. 

In view of the unique theoretical scope of chiral (skew or screw) forms which are capable of determining both polar-electrical and axial-magnetic correlations, and of the prevalence of helical arrangements and left-handed amino acids in organisms, are the C.C. related to helical pulsations, i.e., to change in helical angles ... 

Equation 5 demonstrates the T divergence of the susceptibility and the occurrence of a critical point at T = 0 K. finally, it should be mentioned that the magnetic correlation length, can also be introduced in an equivalent form of the Eq. 5 ... 

For an infinite chain, the relaxation time (r) of the magnetization is activated with the corresponding energy gap (At) expressed as a function of A A and A. The difference between Aa and the total activation energy of r describes the effect of the magnetic correlations. For the infinite chain, the expression of At is ... 

As this expression only rehes on the temperature dependence of the magnetic correlations, Eq. 44 is valid for any Ising-Hke chain independently of the domain wall structure. More specifically, in the case of narrow domain walls and for single-ion anisotropy this expression becomes (using the notations of Eqs. 7a and 23) ... 

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