Development and Application of a Three-dimensional Seismo-acoustic Coupled-mode Model

An increase in the dimension of state space for quantum key distribution (QKD) can decrease its fidelity requirements while also increasing its bandwidth. A significant obstacle for QKD with qu$d$its ($d\geq 3$) has been an efficient and practical quantum state sorter for photons whose complex fields are modulated in both amplitude and phase. We propose such a sorter based on a multiplexed thick hologram, constructed e.g. from photo-thermal refractive (PTR) glass. We validate this approach using coupled-mode theory with parameters consistent with PTR glass to simulate a holographic sorter. The model assumes a three-dimensional state space spanned by three tilted planewaves. The utility of such a sorter for broader quantum information processing applications can be substantial.

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Three-dimensional coupled mode analysis of internal-wave acoustic ducts

The Journal of the Acoustical Society of America ◽

10.1121/1.4869847 ◽

2014 ◽

Vol 135 (5) ◽

pp. 2497-2512 ◽

Cited By ~ 7

Author(s):

Alexey A. Shmelev ◽

James F. Lynch ◽

Ying-Tsong Lin ◽

Henrik Schmidt

Keyword(s):

Internal Wave ◽

Three Dimensional ◽

Mode Analysis ◽

Coupled Mode ◽

Acoustic Ducts

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A new model for the three-dimensional propagation of water waves in the presence of vertically sheared, horizontally varying currents

10.5194/egusphere-egu2020-18933 ◽

2020 ◽

Author(s):

Julien Touboul ◽

Kostas Belibassakis

Keyword(s):

Water Waves ◽

Water Wave ◽

Wave Scattering ◽

Three Dimensional ◽

Water Wave Scattering ◽

Coupled Equations ◽

Coupled Mode ◽

Constant Shear ◽

Mild Slope Equation ◽

Sea Bed

In coastal areas, steep bathymetries and strong currents are often observed. Among several causes, the presence of cliffs, rocky beds, or human structures may cause strong variations of the sea bed, while oceanic circulation, tides, wind action or wave breaking can be responsible for the generation of strong currents. For both coastal safety and engineering purposes, there are many interests in providing efficient models predicting the nonlinear, phase resolved behavior of water waves in such areas. The difficulty is known to be important, and many models achieving that goal are described in the related literature.Recently, it was established that beneath the influence of vertically uniform currents, the vorticity involved in depth varying mean flows could have significant impact on the propagation of water waves (Rey et al. 2014). This gave rise to new derivations of equations aimed to describe this interaction. First, an extended mild slope equation was obtained (Touboul et al. 2016). Then, the now classical coupled mode theory was introduced in the system to obtain a set of coupled equations, which could be compared to the system derived by Belibassakis et al (2011) but considering currents which may present constant shear with depth (Belibassakis et al. 2017, Belibassakis et al., 2019). In these works, the currents were assumed to vary linearly with depth, presenting a constant shear. However, this approach was recently extended to more general configurations (Belibassakis & Touboul, 2019; Touboul & Belibassakis, 2019).In this work, we extend this model to three dimensional configurations. It is emphasized that the model is able to describe rotational waves, as expected, for example, when water waves propagate with a non-zero angle with respect to the current direction (see e.g. Ellingsen, 2016).[1] Rey, V., Charland, J., Touboul, J., Wave &#8211; current interaction in the presence of a 3d bathymetry: deep water wave focusing in opposite current conditions. Phys. Fluids 26, 096601, 2014.[2] Touboul J., Charland J., Rey V., Belibassakis K., Extended Mild-Slope equation for surface waves interacting with a vertically sheared current, Coastal Engineering, 116, 77&#8211;88, 2016.[3] Belibassakis, K.A., Gerostathis, Th., Athanassoulis, G.A. A coupled-mode model for water wave scattering by horizontal, non-homogeneous current in general bottom topography, Applied Ocean Res. 33, 384&#8211; 397, 2011.[4] Belibassakis K.A., Simon B., Touboul J., Rey V., A coupled-mode model for water wave scattering by vertically sheared currents in variable bathymetry regions, Wave Motion, vol.74, 73-92, 2017.[5] Belibassakis K., Touboul J., Laffitte E., Rey&#160; V., A mild-slope system for Bragg scattering of water waves by sinusoidal bathymetry in the presence of vertically sheared currents,&#160; J. Mar. Sci. Eng., Vol.7(1), 9, 2019.[6] Belibassakis K.A., Touboul J. A nonlinear coupled-mode model for waves propagating invertically sheared currents in variable bathymetry-collinear waves and currents, Fluids, 4(2),61, 2019.[7] J. Touboul & K. Belibassakis, A novel method for water waves propagating in the presence of vortical mean flows over variable bathymetry, J. Ocean Eng. and Mar. Energy, https://doi.org/10.1007/s40722-019-00151-w, 2019.[8] Ellingsen, S.A., Oblique waves on a vertically sheared current are rotational, Eur. J. Mech. B-Fluid 56, 156&#8211;160, 2016.

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