Abstract
We reinterpret our earlier letter [Opt. Lett. 32, 2939 (2007)] to demonstrate that the resolution it gives to the problem of the sign of the wave vector and the refractive index is valid for active media without instabilities but invalid otherwise.
| Original language | English |
|---|---|
| Pages (from-to) | 1829 |
| Number of pages | 1 |
| Journal | Optics Letters |
| Volume | 33 |
| Issue number | 16 |
| DOIs | |
| State | Published - 15 Aug 2008 |
| Externally published | Yes |