Theoretical Studies of Spin Dependent Scatterings of Electrons from Ferromagnetic Surfaces and Ultra Thin Films

1991 ◽  
Vol 231 ◽  
Author(s):  
A. Ormeci ◽  
M. P. Gokhale ◽  
Burl M. Hall ◽  
D. L. Mills
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Ab Initio ◽  
Ground State ◽  
Theoretical Studies ◽  
Angle Variation ◽  
Spin Dependent Scattering ◽  
Ultra Thin Film

AbstractWe summarize results of our recent theoretical studies of spin dependent scattering of electrons from ferromagnetic surfaces. We obtain an excellent account of both the energy and angle variation of the exchange asymmetry reported by Waller and Gradmann in their SPLEED study of the Fe(110) surface, and of spin dependent asymmetries in the transmission of photoelectrons through an ultra thin film of Fe on Cu(100). Potentials supplied by Fu and Freeman enable us to account for the data, with use of ground state potentials generated by ab initio methods.

Strain induced super-paramagnetism in Cr2O3 in the ultra thin film limit

2015 ◽  
Vol 1729 ◽  
pp. 79-83 ◽  
Author(s):  
Iori Tanabe ◽  
Haseeb Kazi ◽  
Yuan Cao ◽  
Jack L Rodenburg ◽  
Takashi Komesu ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Magnetic Ordering ◽  
Hysteresis Effect ◽  
Strain Effect ◽  
Temperature Hysteresis ◽  
Antiferromagnetic Ordering ◽  
Show Evidence ◽  
Higher Temperature ◽  
Ultra Thin Film

ABSTRACTUltra thin films of chromia (Cr2O3), less than 3 nm thick, grown epitaxial on α-Al2O3 (sapphire), and are thus compressively strained in-plane. The resulting films show evidence of some magnetic ordering above the Néel temperature of chromia (307 K). The observed higher temperature hysteresis effect observed are very likely a strain effect, and not associated with the typical antiferromagnetic ordering expected of chromia.

scholarly journals Ab initio understanding of magnetic properties in Zn2+ substitution of Fe3O4 ultra-thin film with dilute Zn substitution

AIP Advances ◽  
2018 ◽  
Vol 8 (5) ◽  
pp. 055807
Author(s):  
Zhaocong Huang ◽  
Qian Chen ◽  
Sheng Jiang ◽  
Shuai Dong ◽  
Ya Zhai
Keyword(s):  
Thin Film ◽  
Magnetic Properties ◽  
Ab Initio ◽  
Zn Substitution ◽  
Ultra Thin Film

scholarly journals Study on A-Site Compositional Mixing for the Shear Coating Process of FA-Based Lead Halide Perovskites

2021 ◽  
Vol 59 (5) ◽  
pp. 321-328
Author(s):  
Hansol Kim ◽  
Hyewon Gu ◽  
Minju Song ◽  
Choong-Heui Chung ◽  
Yong-Jun Oh ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Ab Initio Calculations ◽  
Ab Initio ◽  
Perovskite Solar Cells ◽  
Future Research ◽  
Coating Process ◽  
Lead Iodide ◽  
Halide Perovskites ◽  
Halide Perovskite

Halide perovskite solar cells have been attracting tremendous attention as next-generation solar cell materials because of their excellent optical and electrical properties. Formamidinium lead tri-iodide (FAPbI3) exhibits the narrowest band gap among lead iodide perovskites and shows excellent thermal and chemical stability, also. However, the large-area coating of FAPbI3 needed for commercialization has not been successful because of the instability of the black phase of FAPbI3 at ambient temperature. This study presents a compositional engineering direction to control the polymorph of the FAPbI3 thin film for the shear coating processes, without halide mixing. By adopting a hot substrate above 100 oC, our shear coating process can produce the black phase FA-based halide perovskites without halide mixing. We carefully investigate the Cs-FA and MA-FA mixed lead iodide perovskites’ phase stability by combining the study with thin-film fabrication and ab initio calculations. Cs-FA mixing shows promising behaviors for stabilizing α-FAPbI3 (black phase) compared with MA-FA. Stable FA-rich perovskite films cannot be achieved via shear coating processes with MA-FA mixing. Ab initio calculations revealed that Cs-FA mixing is excellent for inhibiting phase decomposition and water incorporation. This study is the first report that FA-based halide perovskite thin films can be made with the shear coating process without MA-Br mixing. We reveal the origin of the stable film formation with Cs-FA mixing, and present future research directions for fabricating FA-based perovskite thin films using shear coating.

scholarly journals Synthesis, characterization and theoretical studies on novel organic–inorganic hybrid ion–gel polymer thin films from a γ-Fe2O3 doped polyvinylpyrrolidone–N-butylpyridinium tetrafluoroborate composite via intramolecular thermal polymerization

RSC Advances ◽  
2017 ◽  
Vol 7 (27) ◽  
pp. 16623-16636 ◽  
Author(s):  
Aswathy Joseph ◽  
Marilyn Mary Xavier ◽  
Gaweł Żyła ◽  
P. Radhakrishnan Nair ◽  
A. S. Padmanabhan ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Thermal Polymerization ◽  
Specific Conductance ◽  
Theoretical Studies ◽  
Inorganic Hybrid ◽  
One Step ◽  
Ion Gel ◽  
High Dielectric ◽  
Material Study

Facile one-step synthesis and material study of novel PVP-ion gel thin film and improvement of ionic conductivity, specific conductance and charge density of it by doping high-dielectric γ-Fe2O3 magnetic nanoparticles is presented here.

Thickness Dependencies in the Calculated Properties of Metallic Ultra-Thin Films

1997 ◽  
Vol 492 ◽  
Author(s):  
J. C. Boettger
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Electronic Structure ◽  
Surface Properties ◽  
Electronic Structure Calculations ◽  
Structure Calculations ◽  
Ultra Thin Film

ABSTRACTUltra-thin film (UTF) electronic structure calculations are a common tool for investigating surface properties. In this work, electronic structure calculations for A1(111) films ranging from one to twelve atoms thick are used to illustrate some of the difficulties that can arise when one attempts to determine surface properties of metals with UTF calculations.

scholarly journals Structure and magnetism in Ga-rich MnGa/GaN thin films and unexpected giant perpendicular anisotropy in the ultra-thin film limit

2016 ◽  
Vol 367 ◽  
pp. 312-319 ◽  
Author(s):  
Andrada-Oana Mandru ◽  
Joseph P. Corbett ◽  
Jeremy M. Lucy ◽  
Andrea L. Richard ◽  
Fengyuan Yang ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Perpendicular Anisotropy ◽  
Ultra Thin Film

Studies on Water in the Hydration Chamber of a Modified Electron Microscope

1970 ◽  
Vol 28 ◽  
pp. 544-545
Author(s):  
R. C. Moretz ◽  
G. G. Hausner ◽  
D. F. Parsons
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Electron Microscope ◽  
Steady State ◽  
Room Temperature ◽  
Small Mass ◽  
Equilibrium Pressure ◽  
Biological Objects ◽  
Mechanical Pump ◽  
Differential Pumping

Use of the electron microscope to examine wet objects is possible due to the small mass thickness of the equilibrium pressure of water vapor at room temperature. Previous attempts to examine hydrated biological objects and water itself used a chamber consisting of two small apertures sealed by two thin films. Extensive work in our laboratory showed that such films have an 80% failure rate when wet. Using the principle of differential pumping of the microscope column, we can use open apertures in place of thin film windows.Fig. 1 shows the modified Siemens la specimen chamber with the connections to the water supply and the auxiliary pumping station. A mechanical pump is connected to the vapor supply via a 100μ aperture to maintain steady-state conditions.

Observations on the growth of YBa2Cu3O7-δ thin films on MgO by pulsed-laser ablation

1991 ◽  
Vol 49 ◽  
pp. 1068-1069
Author(s):  
M. Grant Norton ◽  
C. Barry Carter
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Laser Ablation ◽  
Substrate Surface ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
Laser Ablation Process ◽  
Deposition Parameters

Pulsed-laser ablation has been widely used to produce high-quality thin films of YBa2Cu3O7-δ on a range of substrate materials. The nonequilibrium nature of the process allows congruent deposition of oxides with complex stoichiometrics. In the high power density regime produced by the UV excimer lasers the ablated species includes a mixture of neutral atoms, molecules and ions. All these species play an important role in thin-film deposition. However, changes in the deposition parameters have been shown to affect the microstructure of thin YBa2Cu3O7-δ films. The formation of metastable configurations is possible because at the low substrate temperatures used, only shortrange rearrangement on the substrate surface can occur. The parameters associated directly with the laser ablation process, those determining the nature of the process, e g. thermal or nonthermal volatilization, have been classified as ‘primary parameters'. Other parameters may also affect the microstructure of the thin film. In this paper, the effects of these ‘secondary parameters' on the microstructure of YBa2Cu3O7-δ films will be discussed. Examples of 'secondary parameters' include the substrate temperature and the oxygen partial pressure during deposition.

Sign in / Sign up

Export Citation Format

Share Document