Polaron bound magnetic

A.K. Ramdas and S. Rodriquez, Raman Scattering in Diluted Magnetic Semiconductors P.A. Wolff, Theory of Bound Magnetic Polarons in Semimagnetic Semiconductors... 

The interaction between a charged point defect and neighboring magnetic ions in magnetically doped thin films has been described in terms of a defect cluster called a bound magnetic polaron (Fig. 9.5a). The radius of a bound magnetic polaron due to an electron located on the defect, r, is given by... 

Figure 9.5 Schematic representation of a bound magnetic polaron (a) one bound magnetic polaron located on a charged defect and (b) overlapping bound magnetic polarons leading to ferromagnetic alignment of magnetic ions.

Co0.04Zn0.96O is a ferromagnetic semiconductor, (a) Estimate the radius of a bound magnetic polaron in this material, (b) If the Co2+ ions are uniformly... 

Diet T, Spalek J (1982) Effect of Fluctuations of Magnetization on the Bound Magnetic Polaron - Comparison with Experiment. Phys Rev Lett 48 355-358... 

A rather large negative MR, with a substantial anisotropy, has been observed in reentrant insulating samples with high x (Oiwa et al. 1998b Katsumoto et al. 1998). A destruction of bound magnetic polarons, as invoked in an earlier work on (In.Mn)As... 

In the model of the bound magnetic polaron in EuO (Torrance et al., 1972) quantitative agreement with the experiment can only be obtained by assuming the impurity electron to interact with the ion spins by means of a Jta exchange and not a J t exchange. Thus it seems to be well established that in the Eu chalcogenides and especially in EuO the 6s conduction band is not lower in energy than the 5d band as has been assumed by Kasuya and Yanase (1968). Thus in fig. 19.14 the bottom of the 6s band is shown above the one of the 5d band. 

For the temperature dependence of the conduction band edge in the AF-I, ferrimagnetic, and ferromagnetic states, as obtained from the bound magnetic polaron model, see p. 234. 

Fig. 108. Donor binding energy of the bound magnetic polaron vs. temperature at various magnetic fields as calculated from experimentally determined d.c. resistivity of Eu-rich EuSe with nc(297 K) = 7.8x10 cm". ...

Warnock, J. and Wolff, P.A. (1985) Spherical model of acceptor-associated bound magnetic polarons. Physical Review B Condensed Matter, 31, 6579. 

Dietl, T. and Spalek, J. (1982) Effect of fluctuations of magnetization on the bound magnetic polaron comparison with experiment. Physical Review Letters, 48, 355. 

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