Oceanic lee waves are generated in the deep stratified ocean by flow of currents over sea floor topography, and when they break, can lead to mixing stably interior. While theory linear is well established, nonlinear mechanisms leading still under investigation. Tidally driven have long been observed ocean, along with associated mixing, but observations forced geostrophic eddies relatively spars...

In Letter [1], we reported our finding on the physical origin of wide band-gap opening in planar nanostrips, as derived by application of periodic width modulations in the magnetic waveguides. K. Di et al. in their Comment[2], however, argued that the band gap can be reduced remarkably by applying a linear combination of symmetric and antisymmetric fields (see 'A+B' in the inset of Fig. 1(a)). ...

Using the techniques of quasi-Hermitian quantum mechanics and quantum field theory we use a similarity transformation to construct an equivalent Hermitian Hamiltonian for the Lee model. In the field theory confined to the V/Nθ sector it effectively decouples V , replacing the three-point interaction of the original Lee model by an additional mass term for the V particle and a four-point interac...

Buoyancy perturbations develop when stably stratified air ascends a mountain barrier. These perturbations often trigger disturbances that propagate away from the mountain as gravity (or buoyancy) waves. Gravity waves triggered by the flow over a mountain are referred to as mountain waves or lee waves. Mountain waves sometimes reveal their presence through dramatic cloud formations, such as smoo...