Aydin Koray, Li Zhaofeng, Sahin Levent, Ozbay Ekmel
Nanotechnology Research Center, Department of Physics and Department of Electrical and Electronics Engineering, Bilkent University, Bilkent, 06800, Ankara, Turkey.
Opt Express. 2008 Jun 9;16(12):8835-44. doi: 10.1364/oe.16.008835.
We demonstrate a polarization independent negative-index metamaterial (NIM) at microwave frequencies. Transmission measurements and simulations predict a left-handed transmission band with negative permittivity and negative permeability. A negative-index is verified by using the retrieval procedure. Effective parameters of single-layer and two-layer NIMs are shown to be different. Negative phase advance is verified within the negative-index regime by measuring the phase shift between different sized negative-index metamaterials. Backward wave propagation is observed in the numerical simulations at frequencies where the phase advance is negative.
我们展示了一种在微波频率下与偏振无关的负折射率超材料（NIM）。传输测量和模拟预测了具有负介电常数和负磁导率的左手传输带。通过使用检索程序验证了负折射率。结果表明，单层和两层NIM的有效参数不同。通过测量不同尺寸的负折射率超材料之间的相移，在负折射率范围内验证了负相位超前。在数值模拟中，在相位超前为负的频率处观察到了反向波传播。
