@conference {Wuestner2010,
	title = {Gain in negative-index metamaterials and slow-light waveguides},
	booktitle = {Proceedings of SPIE - The International Society for Optical Engineering},
	volume = {7754},
	year = {2010},
	note = {cited By 0},
	abstract = {We investigate on the basis of a full three-dimensional spatio-temporal Maxwell-Bloch approach the possibility of complete loss compensation in non-bianisotropic negative refractive index (NRI) metamaterials. We show that a judicious incorporation of optically pumped gain materials, such as laser dyes, into a double-fishnet metamaterial can enable gain in the regime where the real part n' of the resulting effective refractive index (n = n' + in") is negative. It is demonstrated that a frequency band exists for realistic opto-geometric and material (gain/loss) parameters where n' < 0 and simultaneously n" < 0 hold, resulting in a figure-of-merit that diverges at two distinct frequency points. Having ensured on the microscopic, meta-molecular level that realistic levels of losses and even gain are accessible in the considered optical frequency regime we explore the possibility of compensating propagation losses in a negative refractive index slow-light metamaterial heterostructure. The heterostructure is composed of a negative refractive index core-layer bounded symmetrically by two thin active cladding layers providing evanescent gain to the propagating slow light pulses. It is shown that backward-propagating light - having anti-parallel phase and group velocities and experiencing a negative effective refractive index - can be amplified inside this slow-light waveguide structure. Our results provide a direct and unambiguous proof that full compensation of losses and attainment of gain are possible on the microscopic as well as the macroscopic level in the regime where the non-bianisotropic refractive index is negative - including, in particular, the regime where the guided light propagates slowly. {\textcopyright} 2010 SPIE.},
	doi = {10.1117/12.871948},
	url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-79751520302\&doi=10.1117\%2f12.871948\&partnerID=40\&md5=4b895df0b6f659a9a30aaeffe92fefcf},
	author = {Wuestner, S. and Kirby, E.I. and Pusch, A. and K. L. Tsakmakidis and Hamm, J.M. and Hess, O.}
}
