IOM 2020, Експеримент — Задача 14

• Q.14 b) No
• Q.14 c) This is due to the laser beam divergence.

Answer 14 a)

You need to plot somewhere all three graphs P (2w) versus P (w). Understand that you need to take the power P (2w) with the same power and maximum possible power P (w).

Plot the dependence of P (w) on L. And it is best on a double logarithmic scale.

There is also a point (0, 0) on the linear scale. There are only three crystals (0.5, 2 and 4 cm), but nobody canceled zero. It can be seen that this is not a power dependence.

On a logarithmic scale (even if there is no zero point), it is obvious that this is not a power dependence.

Answer 14 b) No

From the previous logarithmic graph, you can see that it is impossible.

Answer 14 c) This is due to the laser beam divergence. The divergence width of the laser beam is comparable to the phase matching width for crystals of 2 and 4 cm. Therefore, not all of the beam energy is converted equally effectively into SH. Theory is for plane waves. The longer the crystal, the more it differs from theory.