Focusing Efficiency Analysis and Performance Optimization of Arbitrarily Sized DNG Metamaterial Slabs With Losses

The focusing behavior and optimal design of lossy double-negative (DNG) metamaterial slabs are thoroughly explored in this paper via an efficient technique. To this aim, the novel scheme embodies the signal processing notions of the cross-correlation coefficient and mean square error (mse) to treat structures with convoluted attributes. Furthermore, an enhanced formulation of the latter indicator, devoid of its conventional weaknesses, is introduced. In particular, by neglecting the phase term due to wave propagation in the vacuum/metamaterial space, the modified mse attains far more accurate outcomes without any contrived assumptions. The effectiveness of the prior criteria is successfully examined through the infinite slab case. Next, analysis proceeds to finite-length slabs which are modeled by means of a frequency-dependent finite-difference time-domain algorithm. Numerical verification, addressing diverse complicated DNG arrangements, reveals the advantages of the proposed methodology, indicating its competence to reliably explore the operational characteristics of such demanding media