All Questions
4
questions
20
votes
4
answers
16k
views
"Lack of inversion symmetry" in crystal?
Apparently (first paragraph of this article) the lack of inversion symmetry is some crystals allows all sort of nonlinear optic phenomena.
Now. Does anyone know of an intuitive or just physical ...
- 24.9k
2
votes
2
answers
109
views
Are there any crystallographic effects we can see in the reflection of visible light from metal surfaces?
I started thinking about this in a discussion in comments.
One can start by thinking of the reflection of visible light by most metals as similar to the reflection of radio waves in that it's an ...
- 6,273
1
vote
1
answer
266
views
Can you create high-energy photons using multiple low-energy photons? [duplicate]
I heard once that with a special crystal it's possible to "convert" somehow two green photons to a ultraviolet one and that some UV-lasers are based on this fact. Is this right, and even ...
- 125
1
vote
4
answers
945
views
How do we determine refractive index of a photonic crystal?
Normally, refractive index of a medium is defined as
$$n=\frac c{v_\text{p}},$$
where $c$ is the speed of light in vacuum, and $v_\text{p}$ is the phase speed of light in the medium. Phase speed is ...
- 29.1k