TY - JOUR
AU - Stephanovich, V. A.
AU - Semenov, Yu. G.
PY - 2020/10/09
Y2 - 2020/11/27
TI - The Magnetic Domain Structure Properties in Diluted Magnetic Semiconductors
JF - Ukrainian Journal of Physics
JA - Ukr. J. Phys.
VL - 65
IS - 10
SE -
DO - 10.15407/ujpe65.10.881
UR - https://ujp.bitp.kiev.ua/index.php/ujp/article/view/2020200
SP - 881
AB - <p>We present a comprehensive analysis of the domain structure formation in the ferromagnetic<br>phase of diluted magnetic semiconductors (DMS) of the p-type. Our analysis is carried out<br>on the base of the effective magnetic free energy of DMS calculated by us earlier. This free<br>energy, substituting DMS (a disordered magnet) by an effective ordered substance, permits us<br>to apply the standard phenomenological approach to the domain structure calculation. Using<br>the coupled system of Maxwell equations with those obtained by the minimization of the free<br>energy functional, we show the existence of the critical ratio vcr of concentration of charge<br>carriers and magnetic ions such that the sample critical thickness L<sub>cr</sub> (such that the sample<br>is monodomain at L < L<sub>cr</sub>) diverges as v → v<sub>cr</sub>. At v > v<sub>cr</sub>, the sample is monodomain. This<br>feature makes DMS different from conventional ordered magnets, as it gives a possibility to<br>control the sample critical thickness and the emerging domain structure period by a variation<br>of v. As the concentration of magnetic impurities grows, v<sub>cr</sub> → ∞, restoring a conventional<br>behavior of ordered magnets. Above facts have been revealed by the examination of the tem-<br>perature of the transition to an inhomogeneous magnetic state (stripe domain structure) in<br>the slab of a p-type DMS with finite thickness L. Our theory can be easily generalized for an<br>arbitrary disordered magnet.</p>
ER -