visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2018-06-22 16:00 
일시 June 22 (Fri.), 04:00 PM 
장소 #1323, E6-2 
연사 Dr. Daniel Sando 

Physics Seminar

 

 

Tuning functional properties of BiFeO3films using strain and growth chemistry

 

Dr. Daniel Sando

Univ. of New South Wales, Sydney

 

June 22 (Fri.), 04:00 PM

#1323, E6-2

 

Abstract:

Multiferroics – materials with coexisting ferroic orders such as ferroelectricity and (anti)-ferromagnetism – are presently under intense study by virtue of their promise in next-generation data storage devices. Bismuth ferrite (BiFeO3– BFO) is one of the very few that orders above room temperature. In the bulk, BFO is rhombohedral (R), and in thin films [1] its properties are sensitive to strain [2,3]. The discovery of the epitaxially-stabilized “super tetragonal phase” of BFO (T-BFO) [4] incited a flurry of research activity focused on understanding the phase transition and its possible functionalities [5]. T-BFO is also multiferroic, with large ferroelectric polarization and antiferromagnetic order [4], and the strain relaxation-induced T/R phase mixtures and their exceptional piezoelectric responses [6] continue to intrigue and motivate researchers. A particularly important characteristic of this phase mixture is the interconversion between the R,T phases with an applied electric field [6]. Since the oxygen configuration of the R and T polymorphs is different [5], the electronic, magnetic, and optical properties can thus be dynamically modulated. An additional rather crucial (and thus far underexplored) aspect of mixed R/T BFO is the role of chemistryin the formation of the metastable T-phase. Since T-BFO is typically fabricated by pulsed laser deposition, growth parameters can be used as a strong handle to tailor film properties and functionalities.

Here I will describe our work on understanding the influence of strain and growth conditions on the optical, magnetic, and ferroelectric properties of BFO films. I will also show that by precisely controlling fabrication conditions, the formation of the mixed R/T phases in BFO films can be completely suppressed for thicknesses above 70 nm. Such an intriguing result is useful for applications where thicker pure T-BFO films are needed, such as for measuring the expected giant polarization, or for precisely controlling the proportions of the various phases. Finally, through analysis of a large set of epitaxial films, it will be shown that the optical band gap of BFO is rather insensitive to a host of growth and processing parameters [7]. Combined with the numerous other functionalities of this material, one can envisage multifunctional devices, for example, that harvest mechanical and solar energy, or to enhance magnetoelectric coupling at these multiferroic phase boundaries.

References

[1] Sando et al., J. Phys: Condens. Matt. 26, 473201 (2014). 

[2] Infante et al., PRL 105, 057601 (2010). 

[3] Sando et al., Nat. Mater. 12, 641 (2013). 

[4] Bea et al., PRL 102, 217603 (2009). 

[5] Sando et al., Appl. Phys. Rev. 3, 011106 (2016). 

[6] Zeches et al., Science 326, 977 (2009). 

[7] Sando et al., Adv. Opt Mater. 6, 1700836 (2018).

 

 

 Department of Physics, KAIST

번호 날짜 장소 제목
167 2021-04-09 10:00  Zoom webinar  Integrated Lithium Niobate Photonics file
166 2018-09-07 15:00  학술문화관 (E9), 2층 양승택 오디토리움  Recent developments in density functional theory: From new functionals to the nature of the chemical bond file
165 2023-07-20 16:00  CAPP Seminar Room C303, Creation Hall, KAIST Munji Campus  [CAPP Seminar] Cosmoparticle Physics of Dark Universe file
164 2016-11-10 16:00  E6-2. #1323(1st fl.)  Low Dimensional Active Plasmonics and Electron Optics in Graphene
163 2015-06-03 12:00  Room 101, E11  The First Wednesday Multidisciplinary Forum file
162 2019-06-04 17:00  #1323, E6-2  Stochastic nature of bacterial eradication using antibiotics file
161 2023-09-27 16:00  E6, Rm#2501  Chiral Magnets: Domain-Wall Skyrmions and String Theory Realization
160 2018-12-27 16:00  E6-2. 1st fl. #1323  Quantum Innovation (QuIN) Laboratory file
159 2019-10-17 16:00  #1323, E6-2  Top down manipulation of Waves : From Metamaterials, Correlated Disorder, Quantum Analogy, to Digital Processing file
158 2019-08-14 16:00  Rm. 1323, E6  Quantum Optics, at the heart of quantum metrology and quantum information file
157 2023-07-14 11:00  E6-2 #1501  Interfaces engineering of thin film oxides
156 2017-08-16 16:00  #1322 (E6-2. 1st fl.)  Phonon-driven spin-Floquet valleytro-magnetism file
155 2019-10-15 16:00  #1323, E6-2  Moiré superlattices and graphene quasicrystal file
154 2023-05-15 16:00  CAPP Seminar Room C303, Creation Hall, KAIST Munji Campus  Role of dark Higgs boson in DM physics and cosmology file
153 2020-11-17 12:00  Online(Zoom)  Quantum- & Nano-Photonics" 세미나 시리즈 file
152 2020-12-02 10:00  Zoom  Recent progress in Axion Dark Matter eXperiment (ADMX) technology file
151 2016-04-18 15:30  KI빌딩(E4), 강의실 B501 (5F)  First Principles Approaches for Intermolecular Interactions: From Gas-Phase Dimers to Liquid Water and Molecular Crystal Polymorphism file
150 2018-06-22 10:00  E6-6, Lecture Room 119 (1F)  Success in Research Career file
149 2018-11-23 15:00  E6-2. 2st fl. #2501  Entanglement string and Spin Liquid with Holographic duality file
148 2021-02-02 14:30  Zoom  Quantum- & Nano-Photonics 세미나(Integrated Nanophotonics with Metamaterials, Microcomb, and Atomic Systems) file