Configurable and scalable continuous variable quantum networks for measurement-based information protocols or multipartite communication schemes can be obtained via parametric down conversion (PDC) in non-linear waveguides. In this work, we exploit symmetric group velocity matching (SGVM) to engineer the properties of squeezed modes PDC. We identify type II PDC a single waveguide as best suited...

Data collected over more than eight consecutive hours between two source-receiver arrays in a shallow water environment are analyzed through the physics of the waveguide invariant. In particular, the use of vertical arrays on both the source and receiver sides provides source and receiver angles in addition to travel-times associated with a set of eigenray paths in the waveguide. From the trave...

We present an easy way of observing superluminal group velocities using a birefringent optical fiber and other standard devices. In the theoretical analysis, we show that the optical properties of the setup can be described using the notion of "weak value." The experiment shows that the group velocity can indeed exceed c in the fiber; and we report the first direct observation of the so-called ...

Background: Beta-thalassemia major is a severe and lethal hemolytic anemia. Regular transfusion is necessary for avoidance of its complications but it may end to cardiac involvement secondary to iron overload. Angiotensin converting enzyme inhibitors (ACEIs) are useful medications even in early stages of heart failure. We studied the effects of two common ACEIs on improvement of heart function ...

The equivalence of the energy velocity and the group velocity is often taught in university physics. An early proof of the equivalence of the two velocities for one-dimensional water waves was given by Rayleigh [1]. In the 1950s and 1960s many studies [2}4] were done to show the equivalence of the two velocities for more general systems. Later, in the 1990s, Awati and Howes raised a question as...