by naim a. malak physics department an-najah national university, nablus, palestine
DESCRIPTION
The Magnetic Properties of the Anti-collinear Phase under the Effects of a Uniform External Magnetic Field in a Two Dimensional Square Planar System. By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine 7- 8 / May / 2007 Supervised by - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/1.jpg)
The Magnetic Properties of the Anti-collinear Phase under the Effects of a Uniform External Magnetic Field in a Two Dimensional Square
Planar SystemBy
Naim A. MalakPhysics Department
An-Najah National University, Nablus, Palestine
7 -8 / May / 2007
Supervised by Dr. Abdel-Ruhman M. Abu-Labdeh
![Page 2: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/2.jpg)
Outline
Aim
The Model in General Terms
Monte Carlo Method
Results
Summary
![Page 3: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/3.jpg)
Aim
To investigate the magnetic properties of the Anti-collinear Phase under the effects of a
Uniform External Magnetic Field in an Anti-ferromagnetic Dipolar Planar System
![Page 4: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/4.jpg)
The Model in General Terms
Where
a set of two dimensional classical vectors of unit magnitude g : the strength of the dipolar interaction h : the strength of uniform external magnetic field parallel to X-axis
J : the strength of the exchange interaction ( J< 0 )
)))((
3(})({53
ij
rr
ij
gErr
ijjiji
ji
jii
ii
jiji hRSRSJ
,
)()(
}{ i
![Page 5: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/5.jpg)
Monte Carlo Method
• Constructing an infinite plane from replicas of a finite system
• Using the Ewald Summation Technique
• Using the slandered Metropolis Algorithm
![Page 6: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/6.jpg)
Results
![Page 7: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/7.jpg)
![Page 8: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/8.jpg)
![Page 9: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/9.jpg)
Spin Configurations at T=0.1,h=0.1Anti-collinear Phase
![Page 10: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/10.jpg)
Spin Configurations Perpendicular to the applied Field ( Dipolar Anti-ferromagnetic Phase )
![Page 11: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/11.jpg)
Spin Configurations at low T and high field Ferromagnetic Phase
( T=0.1, h=8.0 )
![Page 12: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/12.jpg)
![Page 13: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/13.jpg)
Summary
• The Phase Diagram Confirms The following results:
* First Order Transition from the Dipolar Anti-ferromagnetic Phase to Ferromagnetic Phase
* Second Order Transition from the Dipolar Anti-ferromagnetic Phase to Paramagnetic Phase
• Besides that, Simulation Results exhibit stable (pi/4) spin configurations at very low ( field & temperature
![Page 14: By Naim A. Malak Physics Department An-Najah National University, Nablus, Palestine](https://reader035.vdocuments.mx/reader035/viewer/2022070401/56813733550346895d9ec0ff/html5/thumbnails/14.jpg)
Acknowledgments
• My father
• Dr. Abdel-Ruhman M. Abu Labdeh for supervision
• My friends; for help