# Best Common Folk Materials Slowing Light Down?

1. Feb 5, 2005

### parlous

I'm aware that an Einstein-Bose Condensate can be made to slow EM energies to slow speeds but I really don't have the \$ nor time to make a BEC. I also wouldn't be able to get the BEC shape in any form I need either. Therefore, what materials exist that can help me slow down some photons?

I know that diamond and quartz have relatively high refractive indexes, but am wondering if there are materials with indexes as high as 3.5?

I would trade a lower refractive index for the ability to transfer a large range of energies the same, ie - like diamond. Are there any polymers that can do what I am looking for?

Thanks,
Parlous

2. Feb 5, 2005

### Logik

Well I'm off topic but are the photons really slowed? they still go at the speed of light... they just get absorbed by the material & the re-immited by the material & they then appear slower? am I right ? anyways I don't any materials with higher refractive index then diamonds but what do I know...

3. Feb 5, 2005

### ZapperZ

Staff Emeritus
There are ferroelectric materials with index of refraction in the 100's. The MgCaTi compound that I deal with has index of refraction of 20.

Zz.

4. Feb 8, 2005

### parlous

Thats right logik, photons r just repeatedly absorbed and emitted by matter. For my case this is fine; I'm simple try to stuff as many photons n a space per unit time as possible.

5. Feb 8, 2005

### Laser Jock

Wow, I wish I had seen this thread earlier. The whole point of my PhD thesis was finding a simple material that you could get slow light (group indices ~10^6). One of the simplest is ruby. http://www.optics.rochester.edu/workgroups/boyd/slowlight/slowlight.html [Broken] a link to the group where I did my graduate work. There are several papers you can download from there. Send me a PM if you have any trouble and I can forward copies to you. I can even send you my thesis (pdf) if you want.

BTW, there is nothing special about a BEC in the creation of huge group velocities. Using the same physics, people have created slow light in hot rubidium vapor and other systems.

Last edited by a moderator: Apr 21, 2017 at 12:26 PM
6. Feb 8, 2005

### Gonzolo

Silicon has about that refractive index for some wavelengths. It surely is amongst the cheapest interesting materials too.