Publications
Detailed Information
Room Temperature Ferromagnetism with Large Magnetic Moment at Low Field in Rare-Earth-doped BiFeO3 Thin Films : 상온의 낮은 자기장에서 높은 자기 모멘트를 보이는 희토류가 첨가된 비스무스 철산화물의 강자성
DC Field | Value | Language |
---|---|---|
dc.contributor.advisor | Nguyen Hoa Hong | - |
dc.contributor.author | 김태영 | - |
dc.date.accessioned | 2017-07-19T09:15:46Z | - |
dc.date.available | 2017-07-19T09:15:46Z | - |
dc.date.issued | 2013-02 | - |
dc.identifier.other | 000000008391 | - |
dc.identifier.uri | https://hdl.handle.net/10371/131679 | - |
dc.description | 학위논문 (석사)-- 서울대학교 대학원 : 물리·천문학부(물리학전공), 2013. 2. Nguyen Hoa Hong. | - |
dc.description.abstract | BiFeO3 is a promising multiferroic material due to its high ferroelectric (1103 K) and antiferromagnetic (643 K) ordering temperatures. Previous reports have suggested that by reducing the dimensionality, the spiral magnetic ordering could be suppressed | - |
dc.description.abstract | therefore, the magnetic properties could be modified. In BiFeO3, if Bi is partially substituted by a small amount of divalent or trivalent metal ions, or Fe is substituted by transition metal ion, a significant enhancement in magnetization can be achieved. Thin films of Rare Earth (Re) - doped BiFeO3 (where RE = Sm, Ho, Pr and Nd) were grown on LaAlO3 substrates by using pulsed laser deposition technique. All the films show a single phase of rhombohderal structure with space group R3c. The saturated magnetization in the Ho- and Sm- doped films is much larger than those reported in literature, and was observed at a quite low field as of 0.2 T. In the case of Ho and Sm doping, the magnetization increases when the film becomes thinner, suggesting that the observed magnetism is mostly due to surface effect. In the case of Nd doping, even though the thin film has large magnetic moment, the mechanism seems to be different. | - |
dc.description.tableofcontents | Contents
ABSTRACT………………………………………………………………Ⅰ List of Figures………………………………………………………………V List of Tables………………………………………………………………VII Chapter 1: Introduction……………………………………………………1 1.1. Multiferroic materials | - |
dc.description.tableofcontents | Bismuth Ferrite Oxides (BFO).……1
1.2. Ferromagnetic enhancement in BiFeO3 thin films: Dimension and Doping ………………………………………3 Chapter 2: Experimental Methods……………………………………4 2.1. Sample Preparation…………………………………………4 2.1.1. Sol-gel auto ignition Method……………………………..5 2.1.2. Pulsed Laser Deposition (PLD)…………………………5 2.2. Measurements………………………………………………7 2.2.1. X-Ray Diffraction (XRD)………………………………………7 2.2.2. Superconducting Quantum Interference Device (SQUID) ……………………………………………………………8 2.2.3. X-Ray Photoelectron Spectroscopy (XPS) .........…………9 Chapter 3: Results and Discussions………………………………………10 3.1. Structural Properties………………………………………10 3.2. Magnetic Properties…………………………………………13 3.2.1. Sm- and Ho- doped BFO thin films…………………………………13 3.2.2. RE- doped BFO thin films ………………………………………17 3.3. BFO Films Chemical States………………………………20 Chapter 4: Conclusions……………………………………………………………22 Appendix…………………………………………………………………23 References…………………………………………………………………25 국문초록 (Abstract in Korean)…………………………………………26 감사의 글 (Acknowledgements)………………………………………27 | - |
dc.format | application/pdf | - |
dc.format.extent | 1648631 bytes | - |
dc.format.medium | application/pdf | - |
dc.language.iso | en | - |
dc.publisher | 서울대학교 대학원 | - |
dc.subject.ddc | 523 | - |
dc.title | Room Temperature Ferromagnetism with Large Magnetic Moment at Low Field in Rare-Earth-doped BiFeO3 Thin Films | - |
dc.title.alternative | 상온의 낮은 자기장에서 높은 자기 모멘트를 보이는 희토류가 첨가된 비스무스 철산화물의 강자성 | - |
dc.type | Thesis | - |
dc.description.degree | Master | - |
dc.citation.pages | 36 | - |
dc.contributor.affiliation | 자연과학대학 물리·천문학부(물리학전공) | - |
dc.date.awarded | 2013-02 | - |
- Appears in Collections:
- Files in This Item:
Item View & Download Count
Items in S-Space are protected by copyright, with all rights reserved, unless otherwise indicated.