Periodic waveguide array

Finally, let us also mention that recent experiments on propagation of electric fields in periodic waveguide arrays provide a classical analog of a simple quanfum sysfem showing exponential decay [27, 28]. These experi-menfs may allow one fo reach fhe posf-exponenfial regime in a particularly direct way, as we will discuss later. 

Ruan Z, Qiu M (2006) Enhanced transmission through periodic arrays of subwavelength holes the role of localized waveguide resonances. Phys Rev Lett 96 233901... 

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