Transmission Electron Microscopy Study of Y2O3 Nanotips Grown on LaAlO3

Y2O3 is a super refractory oxide with high thermal stability and finds various applications in optics and microelectronic devices. Recently, Eu-activated Y2O3 films attracted much research interest due to its promising applications in flat panel field emission displays. Epitaxial Y2O3:Eu thin films have been grown on LaA1O3(LAO). in this paper we report a transmission electron microscopy (TEM) study of Y2O3 nano tip-structure grown on LAO by pulsed laser deposition using stoichiometric YBa2Cu3O7-σ.a target under a low oxygen pressure. The experimental work was conducted within a JEOL2010F TEM equipped with an ED AX system.Fig.l is a low magnification cross-section TEM image of the nano-tip structure grown on (001) LAO. The lattice parameters of the tips were calculated to be that of Y2O3 by using LAO as a standard for indexing the diffraction patterns. Nano electron beam diffraction patterns from the tips along [100] and [110] axis are shown in Fig.2a and Fig.2b, respectively, in agreement with the simulated ones using bulk Y2O3 structure.

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HIGH RESOLUTION TRANSMISSION ELECTRON MICROSCOPY STUDY OF CRYSTALLOGRAPHY AND MORPHOLOGY OF TiC PRECIPITATES IN ARGON IRRADIATED 18Cr10NiTi STEEL

10.46813/2021-135-026 ◽

2021 ◽

pp. 26-31

Author(s):

A.S. Kalchenko ◽

S.A. Karpov ◽

G.D. Tolstolutskaya

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Resolution ◽

Bubble Formation ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Surrounding Matrix ◽

Transmission Electron ◽

Diffraction Patterns ◽

Relationship Of

This work encompasses identification of the crystal structure and analysis of the TiC precipitates in 18Cr-10Ni-Ti austenitic stainless steel under Ar-ions irradiation. High resolution transmission electron microscopy (HRTEM) and energy dispersive spectroscopy (EDS) are used. Orientation relationship of TiC particles in surrounding matrix are indicated by HRTEM and diffraction patterns. The size of the precipitates is found to be critical: the coherency of TiC is kept at the interfaces when the precipitate is in the stage of nucleation, whereas the growth of precipitate up to 10 nm can lead to the loss of coherency in the austenitic steel. The findings suggest that the incoherent precipitate-matrix interface is an important point defect sink and contributes to inert gas bubble formation at elevated irradiation temperatures.

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TRANSMISSION ELECTRON MICROSCOPY STUDY OF TWIN DOMAIN STRUCTURES IN YBa2Cu3O7−x SUPERCONDUCTOR

Modern Physics Letters B ◽

10.1142/s0217984988001545 ◽

1988 ◽

Vol 01 (11n12) ◽

pp. 443-453

Author(s):

LIYING CAI ◽

GANGKAI ZHAO ◽

MEIJUAN ZHAO ◽

MEIZHEN ZHANG ◽

XIAOWEN ZHANG

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Domain Boundary ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Twin Domain ◽

Domain Structures ◽

Transmission Electron ◽

Diffraction Patterns ◽

Lattice Planes

The study of the twin domain structure of YBa2Cu3O7−x superconductor synthesized by coprecipitation method has been carried out by using the transmission electron microscopy. It was found that the twin domain boundary was parallel to the (110) lattice planes. The twin domain is designated as a 90° one. The same twin structure exhibited different characteristics of spot splitting in its selected area eletron diffraction patterns (SADP) when it was irradiated in different incidence directions. The experimental results were satisfactorily consistent with the theoretical calculation. The mechanism of the formation of 90° twin domain has also been discussed. The phase transformation from tetragonal to orthorhombic taking place in YBa2Cu3O7−x ceramics during cooling is considered to be of the “Martensite”.

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Transmission Electron Microscopy study of Bi-based superconducting phases

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173388 ◽

1990 ◽

Vol 48 (4) ◽

pp. 50-51

Author(s):

J.G. Wen ◽

K.K. Fung

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Single Crystals ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Space Groups ◽

Superconducting Phases ◽

Ceramic Samples ◽

Transmission Electron ◽

Modulated Structures

Bi-based superconducting phases have been found to be members of a structural series represented by Bi2Sr2Can−1Cun−1On+4, n=1,2,3, and are referred to as 2201, 2212, 2223 phases. All these phases are incommensurate modulated structures. The super space groups are P2/b, NBbmb 2201, 2212 phases respectively. Pb-doped ceramic samples and single crystals and Y-doped single crystals have been studied by transmission electron microscopy.Modulated structures of all Bi-based superconducting phases are in b-c plane, therefore, it is the best way to determine modulated structure and c parameter in diffraction pattern. FIG. 1,2,3 show diffraction patterns of three kinds of modulations in Pb-doped ceramic samples. Energy dispersive X-ray analysis (EDAX) confirms the presence of Pb in the three modulated structures. Parameters c are 3 0.06, 38.29, 30.24Å, ie 2212, 2223, 2212 phases for FIG. 1,2,3 respectively. Their average space groups are all Bbmb.

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