Journal
PHYSICAL REVIEW A
Volume 79, Issue 2, Pages -Publisher
AMER PHYSICAL SOC
DOI: 10.1103/PhysRevA.79.023839
Keywords
-
Categories
Funding
- Engineering and Physical Sciences Research Council [EP/E031463/1]
- Engineering and Physical Sciences Research Council [EP/E031463/1] Funding Source: researchfish
- EPSRC [EP/E031463/1] Funding Source: UKRI
Ask authors/readers for more resources
Materials that exhibit loss or gain have a complex-valued refractive index n. Nevertheless, when considering the propagation of optical pulses, using a complex n is generally inconvenient-hence the standard choice of real-valued refractive index, i.e., n(s) = Re(root n(2)). However, an analysis of pulse propagation based on the second-order wave equation shows that use of n(s) results in a wave vector different to that actually exhibited by the propagating pulse. In contrast, an alternative definition n(c) = root Re(n(2)), always correctly provides the wave vector of the pulse. Although for small loss the difference between the two is negligible, in other cases it is significant; it follows that phase and group velocities are also altered. This result has implications for the description of pulse propagation in near resonant situations, such as those typical of metamaterials with negative (or otherwise exotic) refractive indices.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available