Low-loss triangular left- and right-handed metamaterials

A single-sided left- and right-handed metamaterial, which is called a triangular left- and right-handed resonator composed of symmetric paired triangular split-rings and middle wires, is discussed. The frequency dependence of the transmittance shows a right-handed transmission window centred around 9.9 GHz and a left-handed transmission peak around 10.9 GHz, both displaying comparable high transmission levels. The left- and right-handed behaviour is assessed by retrieved effective parameters, surface current distribution and comparison of the phase delay between two slabs of different units.