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Magnetism of Two-Dimensional Ferromagnetic Materials.

Record Type:	Language materials, manuscript : Monograph/item
Title/Author:	Magnetism of Two-Dimensional Ferromagnetic Materials./
Author:	Ibrahim, Essa Muhammad.
Description:	1 online resource (77 pages)
Notes:	Source: Dissertations Abstracts International, Volume: 85-06, Section: B.
Contained By:	Dissertations Abstracts International85-06B.
Subject:	Physics. -
Online resource:	click for full text (PQDT)
ISBN:	9798381176230

Magnetism of Two-Dimensional Ferromagnetic Materials.
Ibrahim, Essa Muhammad.

Magnetism of Two-Dimensional Ferromagnetic Materials. - 1 online resource (77 pages)

Source: Dissertations Abstracts International, Volume: 85-06, Section: B.

Thesis (Ph.D.)--The University of Arizona, 2023.

Includes bibliographical references

In recent years, the discovery of numerous two-dimensional (2D) magnetic materials exhibiting unique magnetic and spin transport properties has opened up new possibilities for spintronics applications. While long-range ferromagnetic ordering is theoretically unstable in 2D systems due to strong thermal fluctuations, this can be overcome by introducing anisotropy, which breaks continuous symmetry and allows for the emergence of long-range order. But still, the magnetization magnitude in 2D systems depends on both the exchange interaction and the total effective field, even at low temperatures, in contrast to 3D systems in which the magnetization magnitude only depends on the exchange interaction. Thus, two-dimensional magnetization is fundamentally different than three-dimensional magnetization.In this dissertation, we employ a self-consistent Random Phase Approximation to analytically investigate magnetization in 2D systems, accounting for the significant spin fluctuations. We examine the impact of random fields on 2D magnets and reveal a shift from a second-order to a first-order phase transition. Additionally, we develop a two-dimensional quantum Stoner-Wohlfarth model, demonstrating the temperature dependence of hysteresis and astroid diagrams, which differs from the 3D case. Finally, our simulation of the magnetization reversal dynamics in a 2D single-domain magnet shows that the process usually involves magnetization collapse followed by remagnetization in the direction of the external field, resulting in a significantly shorter reversal time.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2024

Mode of access: World Wide Web

ISBN: 9798381176230Subjects--Topical Terms:

564049
Physics.
Subjects--Index Terms:

Magnetic switchingIndex Terms--Genre/Form:

554714
Electronic books.

Magnetism of Two-Dimensional Ferromagnetic Materials.
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500 $a Source: Dissertations Abstracts International, Volume: 85-06, Section: B.
500 $a Advisor: Zhang, Shufeng.
502 $a Thesis (Ph.D.)--The University of Arizona, 2023.
504 $a Includes bibliographical references
520 $a In recent years, the discovery of numerous two-dimensional (2D) magnetic materials exhibiting unique magnetic and spin transport properties has opened up new possibilities for spintronics applications. While long-range ferromagnetic ordering is theoretically unstable in 2D systems due to strong thermal fluctuations, this can be overcome by introducing anisotropy, which breaks continuous symmetry and allows for the emergence of long-range order. But still, the magnetization magnitude in 2D systems depends on both the exchange interaction and the total effective field, even at low temperatures, in contrast to 3D systems in which the magnetization magnitude only depends on the exchange interaction. Thus, two-dimensional magnetization is fundamentally different than three-dimensional magnetization.In this dissertation, we employ a self-consistent Random Phase Approximation to analytically investigate magnetization in 2D systems, accounting for the significant spin fluctuations. We examine the impact of random fields on 2D magnets and reveal a shift from a second-order to a first-order phase transition. Additionally, we develop a two-dimensional quantum Stoner-Wohlfarth model, demonstrating the temperature dependence of hysteresis and astroid diagrams, which differs from the 3D case. Finally, our simulation of the magnetization reversal dynamics in a 2D single-domain magnet shows that the process usually involves magnetization collapse followed by remagnetization in the direction of the external field, resulting in a significantly shorter reversal time.
533 $a Electronic reproduction. $b Ann Arbor, Mich. : $c ProQuest, $d 2024
538 $a Mode of access: World Wide Web
650 4 $a Physics. $3 564049
650 4 $a Theoretical physics. $3 1180318
650 4 $a Condensed matter physics. $3 1148471
653 $a Magnetic switching
653 $a Magnetism
653 $a Magnetization dynamics
653 $a Quantum Stoner Wohlfarth model
653 $a Random fields
653 $a Two-dimensional magnets
653 $a Spintronics
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