Lattice defects in single-crystal lithium niobate II. Electric fields of dislocations and small-angle grain boundaries

ABSTRACTA strong attenuation of surface acoustic waves in the range of 30 to 100 MHz by singlewalled carbon nanotube layers deposited on the surface of piezoelectric lithium niobate single crystal has been observed. The attenuation exhibits non-monotonous dependence on nanotube density. This attenuation is attributed to the acoustoelectronic interaction between electric fields of the SAW and charge carriers in the nanotubes. The experimental results are in the qualitative agreement with the theory of acoustoelectronic interaction in inhomogeneous structures.

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Effect of small-angle grain boundaries on polishing quality of lithium niobate substrates

Crystal Research and Technology ◽

10.1002/crat.2170201123 ◽

1985 ◽

Vol 20 (11) ◽

pp. K115-K117

Author(s):

E. Neumann ◽

H. Schulz

Keyword(s):

Lithium Niobate ◽

Grain Boundaries ◽

Small Angle

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The observation of defects on (100) CdTe surfaces by chemical etching

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131759 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1424-1425

Author(s):

M.E. Lee

Keyword(s):

Single Crystal ◽

Grain Boundaries ◽

Single Crystals ◽

Chemical Etching ◽

Crystalline Perfection ◽

Crystalline Defects ◽

High Incidence ◽

Crystallographic Defects ◽

Cdznte Substrates ◽

Device Technology

The crystalline perfection of bulk CdTe substrates plays an important role in their use in infrared device technology. The application of chemical etchants to determine crystal polarity or the density and distribution of crystallographic defects in (100) CdTe is not well understood. The lack of data on (100) CdTe surfaces is a result of the apparent difficulty in growing (100) CdTe single crystal substrates which is caused by a high incidence of twinning. Many etchants have been reported to predict polarity on one or both (111) CdTe planes but are considered to be unsuitable as defect etchants. An etchant reported recently has been considered to be a true defect etchant for CdTe, MCT and CdZnTe substrates. This etchant has been reported to reveal crystalline defects such as dislocations, grain boundaries and inclusions in (110) and (111) CdTe. In this study the effect of this new etchant on (100) CdTe surfaces is investigated.The single crystals used in this study were (100) CdTe as-cut slices (1mm thickness) from Bridgman-grown ingots.

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Electro-Optic Control of Lithium Niobate Bulk Whispering Gallery Resonators: Analysis of the Distribution of Externally Applied Electric Fields

Crystals ◽

10.3390/cryst11030298 ◽

2021 ◽

Vol 11 (3) ◽

pp. 298

Author(s):

Yannick Minet ◽

Hans Zappe ◽

Ingo Breunig ◽

Karsten Buse

Keyword(s):

Lithium Niobate ◽

Electric Field ◽

Electric Fields ◽

Frequency Comb ◽

Parametric Oscillation ◽

Pockels Effect ◽

Optical Mode ◽

Cylindrical Resonator ◽

Whispering Gallery ◽

Electro Optic

Whispering gallery resonators made out of lithium niobate allow for optical parametric oscillation and frequency comb generation employing the outstanding second-order nonlinear-optical properties of this material. An important knob to tune and control these processes is, e.g., the linear electro-optic effect, the Pockels effect via externally applied electric fields. Due to the shape of the resonators a precise prediction of the electric field strength that affects the optical mode is non-trivial. Here, we study the average strength of the electric field in z-direction in the region of the optical mode for different configurations and geometries of lithium niobate whispering gallery resonators with the help of the finite element method. We find that in some configurations almost 100% is present in the cavity compared to the ideal case of a cylindrical resonator. Even in the case of a few-mode resonator with a very thin rim we find a strength of 90%. Our results give useful design considerations for future arrangements that may benefit from the strong electro-optic effect in bulk whispering gallery resonators made out of lithium niobate.

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Interdomain region in single-crystal lithium niobate bimorph actuators produced by light annealing

Crystallography Reports ◽

10.1134/s1063774515040136 ◽

2015 ◽

Vol 60 (5) ◽

pp. 700-705 ◽

Cited By ~ 15

Author(s):

I. V. Kubasov ◽

M. S. Timshina ◽

D. A. Kiselev ◽

M. D. Malinkovich ◽

A. S. Bykov ◽

...

Keyword(s):

Lithium Niobate ◽

Single Crystal ◽

Bimorph Actuators

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Depressed scattering across grain boundaries in single crystal graphene

Applied Physics Letters ◽

10.1063/1.4758464 ◽

2012 ◽

Vol 101 (17) ◽

pp. 172107 ◽

Cited By ~ 4

Author(s):

Jiao Chen ◽

Zhi Jin ◽

Peng Ma ◽

Hong Wang ◽

Haomin Wang ◽

...

Keyword(s):

Single Crystal ◽

Grain Boundaries

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Effect of grain boundaries in La0.84Sr0.16CoO3−δ on oxygen diffusivity and surface exchange kinetics

Physical Chemistry Chemical Physics ◽

10.1039/d1cp01099a ◽

2021 ◽

Author(s):

Natalia Porotnikova ◽

Andrei Farlenkov ◽

Sergey Naumov ◽

Maxim Vlasov ◽

Anna Khodimchuk ◽

...

Keyword(s):

Single Crystal ◽

Grain Boundaries ◽

Gas Phase ◽

Oxygen Exchange ◽

Polycrystalline Specimen ◽

Surface Exchange ◽

Oxygen Diffusivity ◽

Exchange Kinetics ◽

Oriented Single Crystal

The 16O/18O oxygen exchange kinetics between the gas phase and the oriented single crystal and polycrystalline specimen has been studied; the rates of individual stages of oxygen exchange have been calculated and discussed.

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