scholarly journals Canalization acoustic phonon polaritons in metal-MoO3-metal sandwiched structures for nano-light guiding and manipulation

2021 ◽  
Author(s):  
Qizhi Yan ◽  
Runkun Chen ◽  
Zhu Yuan ◽  
Peining Li ◽  
Xinliang Zhang
Keyword(s):  
Electromagnetic Field ◽  
Double Layer ◽  
Layered Structure ◽  
Acoustic Phonon ◽  
Molybdenum Trioxide ◽  
Electromagnetic Mode ◽  
Α Phase ◽  
Phonon Polaritons ◽  
Metal Layers

Abstract We theoretically propose and study in-plane anisotropic acoustic phonon polaritons (APhPs) based on a layered structure consisting of a monolayer (or few layers) α-phase molybdenum trioxide (α-MoO3) sandwiched between two metal layers. We find that the APhPs in the proposed sandwiched structures are a canalization (highly directional) electromagnetic mode propagating along with the layers and at the same time exhibit extreme electromagnetic-field confinement surpassing any other type of phonon-polariton modes. When a double layer of α-MoO3 is sandwiched by two Au layers, twisting the two α-MoO3 layers can adjust the interlayer polaritonic coupling and thus manipulate the in-plane propagation of the highly confined APhPs. Our results illustrate that the metal-MoO3-metal sandwiched structures are a promising platform for light guiding and manipulation at ultimate scale.

scholarly journals Enabling propagation of anisotropic polaritons along forbidden directions via a topological transition

2021 ◽  
Vol 7 (14) ◽  
pp. eabf2690
Author(s):  
J. Duan ◽  
G. Álvarez-Pérez ◽  
K. V. Voronin ◽  
I. Prieto ◽  
J. Taboada-Gutiérrez ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Silicon Carbide ◽  
Molybdenum Trioxide ◽  
Real Space ◽  
Negative Permittivity ◽  
Topological Transition ◽  
Α Phase ◽  
Direct Light ◽  
Gap Opening ◽  
Phonon Polaritons

Polaritons with directional in-plane propagation and ultralow losses in van der Waals (vdW) crystals promise unprecedented manipulation of light at the nanoscale. However, these polaritons present a crucial limitation: their directional propagation is intrinsically determined by the crystal structure of the host material, imposing forbidden directions of propagation. Here, we demonstrate that directional polaritons (in-plane hyperbolic phonon polaritons) in a vdW crystal (α-phase molybdenum trioxide) can be directed along forbidden directions by inducing an optical topological transition, which emerges when the slab is placed on a substrate with a given negative permittivity (4H–silicon carbide). By visualizing the transition in real space, we observe exotic polaritonic states between mutually orthogonal hyperbolic regimes, which unveil the topological origin of the transition: a gap opening in the dispersion. This work provides insights into optical topological transitions in vdW crystals, which introduce a route to direct light at the nanoscale.

Effect of Electromagnetic Field on the Solidification Structure of HMn084 Brass

2011 ◽  
Vol 201-203 ◽  
pp. 2904-2908
Author(s):  
Bao Mian Li ◽  
Hai Tao Zhang ◽  
Jian Zhong Cui
Keyword(s):  
Electromagnetic Field ◽  
Uniform Distribution ◽  
Phase Changes ◽  
Solidification Structure ◽  
Current Intensity ◽  
Silicide Phase ◽  
Cast Structure ◽  
Β Phase ◽  
Α Phase

The effect of electromagnetic field on the solidification structure of HMn084 brass (Cu-20%Zn-7.5%Mn-5.5%Al-1.5%Si-1%Fe-0.5%Pb in mass%) had been investigated in this paper. The results show that the as-cast structure of HMn084 brass is composed of matrix β-phase, small amount of α-phase and silicide (Mn, Fe)5Si3. Applying electromagnetic field during the solidification of HMn084 brass can refine grain and silicide phase, promote the uniform distribution of silicide phase. The morphology of silicide phase changes from coarse acicular and massive shape to fine acicular and massive shape. The above-mentioned effects become more obvious with the increasing in current intensity.

Ultralow power switching in a silicon-rich SiNy/SiNx double-layer resistive memory device

2017 ◽  
Vol 19 (29) ◽  
pp. 18988-18995 ◽  
Author(s):  
Sungjun Kim ◽  
Yao-Feng Chang ◽  
Min-Hwi Kim ◽  
Suhyun Bang ◽  
Tae-Hyeon Kim ◽  
...  
Keyword(s):  
Low Power ◽  
Double Layer ◽  
Resistive Switching ◽  
Layered Structure ◽  
Memory Device ◽  
Resistive Memory ◽  
Power Switching ◽  
Ultralow Power

Here we demonstrate low-power resistive switching in a Ni/SiNy/SiNx/p++-Si device by proposing a double-layered structure (SiNy/SiNx), where the two SiN layers have different trap densities.

scholarly journals STUDY OF WEAR RESISTANCE OF THE CU-AL SYSTEM LAYERED METAL-INTERMETALLIDE COMPOSITES

2021 ◽  
pp. 18-26
Author(s):  
V. G. Shmorgun ◽  
O. V. Slautin ◽  
V. P. Kulevich ◽  
A. A. Artemiev ◽  
V. O. Kharlamov ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Layered Structure ◽  
Wear Testing ◽  
Wear Particles ◽  
Soft Metal ◽  
Copper Aluminum ◽  
Metal Layers ◽  
Intermetallic Layers

The results of wear testing of the SMIC of the copper-aluminum system at the angle of action of the abrasive relative to the metal-intermetallic layers - 0, 45 and 90º are given. It is shown that the wear resistance of SMIC is 3.2 ÷ 3.3 times higher than that of AD1 aluminum. At the same time, the samples showed the best indicators of wear resistance when the abrasive was applied to the layered structure of the tested SMIC at an angle of 45º. Analysis of the wear surfaces obtained by friction in all directions with respect to the layers of the SMIC made it possible to identify all the main morphological types of wear particles in the conglomerate. It is shown that additional saturation of the hard phases (intermetallic or abrasive) with pressed particles of soft metal layers contributes to the implementation of the Charpy principle.

Extremely Confined Acoustic Phonon Polaritons in Monolayer-hBN/Metal Heterostructures for Strong Light–Matter Interactions

ACS Photonics ◽  
2020 ◽  
Vol 7 (9) ◽  
pp. 2610-2617
Author(s):  
Zhu Yuan ◽  
Runkun Chen ◽  
Peining Li ◽  
Alexey Y. Nikitin ◽  
Rainer Hillenbrand ◽  
...  
Keyword(s):  
Acoustic Phonon ◽  
Strong Light ◽  
Phonon Polaritons

Fine structure of Tyloses in three species of the Myrtaceae

1967 ◽  
Vol 15 (1) ◽  
pp. 25 ◽  
Author(s):  
RC Foster
Keyword(s):  
Fine Structure ◽  
Granular Material ◽  
Double Layer ◽  
Layered Structure ◽  
Outer Layer ◽  
Secondary Wall ◽  
Pit Membrane ◽  
Ray Cell

The tylosis wall in Eucalyptus obliqua L'Herit. is shown to be composed of two microfibrillar layers. The outer layer (T1), with randomly orientated microfibrils, is covered with amorphous granular material. The inner layer (T2) is multilamellate. In sclerosed tyloses of E. miniata A. Cunn., each lamella of T2 is composed of many layers of microfibrils. Simple pits, delineated by circumferentially orientated microfibrils, are found in both sclerosed and non-sclerosed tyloses. The tylosis in E. obliqua is shown to arise from a two-layered structure formed within the secondary wall of the ray cell. This layer extends into the pit chamber, covering the pit membrane on the ray side. Following the breakdown of the vestures and the pit membrane, this double layer bulges out into the vessel to form the tylosis.

Properties of MoO3 Thin Film Polymorphs

1986 ◽  
Vol 77 ◽  
Author(s):  
E. M. McCARRON ◽  
P. F. Carcia
Keyword(s):  
Thin Film ◽  
Oxygen Partial Pressure ◽  
Partial Pressure ◽  
Layered Structure ◽  
Molybdenum Trioxide ◽  
Preferred Orientation ◽  
Related Structure

ABSTRACTThin film polymorphs of molybdenum trioxide have been synthesized by RF sputtering. Films deposited on thermally floating substrates are polycrystalline and exhibit preferred orientation. Depending upon the oxygen partial pressure maintained during sputtering, the films can be made to crystallize in either the thermodynamically stable orthorhombic a MoO3 form (unique 2D-layered structure) or the metastable monoclinic /3 MoO3 phase (3D ReO3-related structure). Metastable β films can be converted thermally to the a phase and the transformation appears topotactic. Films deposited on cooled substrates are amorphous. A correlation between the particular phase formed and adatom mobility is noted.

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