Magnetic phases

In equilibrium, this describes the coexistence of two different phases (solid and liquid), just as in the case of the Ising model ( hising) with the up and down magnetization phases. When h 0, one of these two phases has a priority. Therefore, a sign change of h -h induces a first-order phase transition. (Note that for modeling reasons h(T) may be assumed to depend on temperature.)... 

For example, 0 describes the temperature dependence of composition near the upper critical solution temperature for binary (liquid + liquid) equilibrium, of the susceptibility in some magnetic phase transitions, and of the order parameter in (order + disorder) phase transitions. 

Lorentzian line shapes are expected in magnetic resonance spectra whenever the Bloch phenomenological model is applicable, i.e., when the loss of magnetization phase coherence in the xy-plane is a first-order process. As we have seen, a chemical reaction meets this criterion, but so do several other line broadening mechanisms such as averaging of the g- and hyperfine matrix anisotropies through molecular tumbling (rotational diffusion) in solution. 

At lower temperatures, the standard 3D helical order with all chains having not only the same chirality but also the same phase can be established. The two magnetic phase transitions present very different features. In fact, the transition to the... 

This drawback has been overcome by using rare-earth magnetic materials in the coldest part of the regenerator. These materials have a magnetic phase transitions below 15K, with an increase in their heat capacities (see Section 3.6). However, to find a material suitable for sub 4 K applications is still a challenge. 

Fig. 5 Magnetic phase diagram of [Mn(Cp )2][Pt(tds)2] M(T) (filled diamonds) M(H) (//] (filled triangles), H (filled inverted triangles), x (T) (open circles) x (H) (open squares) Tt is the tricritical temperature I denotes the first-order MM transition II denotes a second-order transition (AF-PM phase houndary) and III denotes a higher order transitions (from a PM to a FM like state). From [45]...

High temperature superconductors (HTS), 23 814, 826, 829. See also Anisotropic HTS HTS entries applications of, 23 852-872 layered, 23 827, 840 magnetic phase diagram of, 23 838-842 p- and n-type, 23 838 structural anisotropy and fluxon line fragmentation in, 23 841 thallium- and mercury-based, 23 848-850... 

Magnetic phase diagram, of high temperature superconductors,... 

Ito H, Kondo T, Sasaki H, Saito G, Ishiguro T (1999) Antiferromagnetic spin resonance and magnetic phase diagram of deuterated /c-(BEDT-TTE)2Cu[N(CN)2]Br. Synth Met 103 1818-1819... 

Fig. 7. Tentative magnetic phase diagram of NpAs. (Blaise et al. >)...

Fig. 6.18 Magnetic phase diagram of Co Sej J2 (Adachi et al 1970). See also Adachi...

Fig. 38. Hall resistance Rnall of an insulated gate (ln.Mn)As field-effect transistor at 22.5 K as a function of the magnetic field for three different gate voltages. /tnaii s proportional to the magnetization of the (In.Mn)As channel. Upper right inset shows the temperature dependence of / Hall- Let inset shows schematically the gate voltage control of the hole concentration and the conesponding change of the magnetic phase (Ohno et al. 2000).

Fig. 57. Magnetoelastic stress isotherms for a (Ho6/Y6)ioo supertattice ora and

Fig. 33. Temperature dependence of the susceptibility of GdNi2B2C measured at 1 Tesla on an oriented powder, indicating the two magnetic phase transitions near 20 K and 14 K (after Felner 2001).

Fig. 35. Magnetic-field-vs.-temperature magnetic phase diagram for TbNi2B2C proposed by Cho et al. (1996a). AF antiferromagnetic WF weakly ferromagnetic. The nature of the intermediate ordered state is not yet...

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