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4

Just as Jon Custer wrote in his comment, even a perfectly collimated laser beam with a planar wavefront will diverge. The way it happens is determined by the Huygens principle, and depends on the beam profile: When the light intensity is abruptly cut by a sharp flat obstacle, the light will indeed diffract in almost all angles. A razor blade cutting a laser ...


3

A properly collimated laser beam is called a Gaussian Beam whose transverse magnetic and electric field amplitude profiles are given by the Gaussian function. The Gaussian beam is a transverse electromagnetic (TEM) mode. The mathematical expression for the electric field amplitude is a solution to the paraxial Helmholtz equation: The width of such laser ...


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If the wall is made of a perfectly reflective material (such as a mirror) no, you won't see the dot. However, most walls are covered with paint or made of a diffusive material : when the laser beam hits the wall, its light gets diffused in all directions. Thus you are able to see the laser spot on the wall. To summarize : reflection depends on the ...


2

A coherent state is actually a mathematical idealization of a monochromatic laser. Strictly speaking, any continuous wave laser in the laboratory would be a statistical mixture of phase-randomized coherent states. Furthermore, it would also have a finite linewidth, and different frequency components in that linewidth would have no definite phase relationship ...


1

Light is stretched by the gravitational wave and you are quite correct that this is the reason we see the cosmological red shift. However the arms of the LIGO interferometer are only 4km long so light takes only 27 microseconds to make the round trip. The maximum frequency of the observed gravitational waves was 250Hz making the period 4 milliseconds. So ...


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i think PIConGPU is the best choice for simulation of laser plasma interaction especially for large scale plasma. the VLPL code has been written by Prof. Pukhov's group and isn't open source. you have to contact to him or his coworkers to get the code. if you have enough time like two or three years for your simulations, you can write your own code by ...



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