Spin waves are propagating disturbances in the magnetization of magnetic materials. One of their interesting properties is nonreciprocity, exhibiting that their amplitude depends on the magnetization direction. Nonreciprocity in spin waves is of great interest in both fundamental science and applications because it offers an extra knob to control the flow of waves for the technological fields o...

We develop an anisotropic plane-wave migration method based on wavefield extrapolation. In this new scheme, we decompose both source and receiver wavefields into plane waves by delaying shots. For each plane wave, we design a tilted coordinate system whose tilting angle depends on the propagation direction of the plane wave. The wavefield extrapolation is done by an implicit isotropic operator ...

Previous studies on elastic wave propagation in fractured media have demonstrated that a single planar fracture supports fracture interface waves and that two plane parallel fractures support fracture channel waves. Here, the results are presented for plane wave propagation through an infinite number of plane parallel fractures with equal fracture spacing and fracture stiffnesses. Analysis of t...

We present the computational results on the formation of diverse complex 3D vortex lattices by a designed superposition of multiple plane waves. Special combinations of multiples of three noncoplanar plane waves with a designed relative phase shift between one another are perturbed by a nonsingular beam to generate various complex 3D vortex lattice structures. The formation of complex gyrating ...

Pure gravitational plane waves are considered as a special case of spacetimes with two commuting spacelike Killing vector elds. Starting with a midisuperspace that describes this kind of spacetimes, we introduce gaugexing and symmetry conditions that remove all non-physical degrees of freedom and ensure that the classical solutions are plane waves. In this way, we arrive at a reduced model with...

Wave-equation based shot-record migration provides accurate images but is computationally expensive because every shot must be migrated separately. Shot-encoding migration, such as random shot-encoding or plane-wave migration, aims to reduce the computational cost of the imaging process by combining the original data into synthesized common-source gathers. Random shot-encoding migration and pla...

We derive the elastic properties of a cylindrical cloak for in-plane coupled shear and pressure waves. The cloak is characterized by a rank 4 elasticity tensor with 16 spatially varying entries which are deduced from a geometric transform. Remarkably, the Navier equations retain their form under this transform, which is generally untrue [Milton et al., New J. Phys. 8, 248 (2006)]. We numericall...

A general class of Lorentzian metrics, M0 ×R, 〈·, ·〉z = 〈·, ·〉x + 2 du dv + H (x, u) du2, with (M0, 〈·, ·〉x ) any Riemannian manifold, is introduced in order to generalize classical exact plane fronted waves. Here, we start a systematic study of their main geodesic properties: geodesic completeness, geodesic connectedness and multiplicity causal character of connecting geodesics. These results ...