Slow Light in Negative Index Metamaterial Heterostructures

In an effort to overcome disadvantages of many previous schemes to realize slow light, a fundamentally new and auspicious approach has been recently proposed (Refs. [12], [13] in Metamaterials). As highlighted above, this method relies on the use of LH-MM waveguides, wherein the power-flow direction inside the LH regions is opposite to the one in the RH regions, resulting in a pronounced deceleration of the guided electromagnetic waves.

Figure 1: Slab heterostructure with NRI core, supporting oscillatory guided modes

The scheme uses efficiently excitable waveguide oscillatory modes and is remarkably simple, since the slowing of the guided modes is performed solely by sufficient decrease of the core thickness. In doing so, we are able to allow for extremely large bandwidths over which the slowing or stopping of the incoming optical signals can be achieved, likewise the PhC technique. However, compared to the PhC method, our approach has the advantage that it can facilitate very efficient butt-coupling, directly to a slow mode alone, because: i) it supports single-mode operation in the slow-light regime, ii) the characteristic impedance of the LH waveguide can be appropriately adjusted by varying the core thickness, and iii) the spatial distribution of the slow mode closely matches that of a single-mode fibre. These conclusions were drawn in [12], [13] following exact manipulations of Maxwell’s equations, without invoking heuristic approximations.  

Figure 2: Geometric dispersion diagram of oscillatory and SPP modes guided by the generalized structure shown in Fig. 1. Note the transition point between the two types of modes.

Figure 3: Dispersion diagram for the second and fifth oscillatory mode, for a specified choice of optical parameters [see Tsakmakidis et al., Appl. Phys. Lett. 89, 201103 (2006)].

Figure 4 Normalized total forward power flow P, versus the reduced slab thickness αk0.

References

[1]  L. V. Hau, S. E. Harris, Z. Dutton, and C. H. Behroozi, Nature (London) 397, 594 (1999).
[2]  C. Liu, Z. Dutton, C. H. Behroozi, and L. V. Hau, Nature (London) 409, 277 (2000).
[3]  L. J. Wang, A. Kuzmich, and A. Dogariu, Nature (London) 406, 277 (2000).
[4]  M. S. Bigelow, N. N. Lepeshkin, and R. W. Boyd, Science 301, 200 (2003).
[5]  D. Gauthier, Phys. World 18, 30 (2005).
[6]  D. J. Blumenthal, et al., “Optical Packet switching and Associated Optical Signal Processing”, available on the Internet.
[7]  D. J. Blumenthal, P. R. Pruncal, and J. R. Sauer, Proc. IEEE 82, 1650 (1994).
[8]  H. Gersen, et al., Phys. Rev. Lett. 94, 073903 (2005).
[9]  J. B. Pendry, Phys. Rev. Lett. 85, 3966 (2000), and references cited therein.
[10]  R. A. Shelby, D. R. Smith, and S. Shultz, Science 292, 77 (2001).
[11]  A. N. Lagarkov and V. N. Kissel, Phys. Rev. Lett. 92, 077401 (2004).
[12]  K. L. Tsakmakidis, A. Klaedtke, C. Jamois, D. P. Aryal, and O. Hess, Appl. Phys. Lett. 89, 201103 (2006).
[13]  K. L. Tsakmakidis, C. Hermann, A. Klaedtke, C. Jamois, and O. Hess, Phys. Rev. B 73, 085104 (2006).