Apex-angle-dependent resonances in triangular split-ring resonators

Along with other frequency selective structures (Pendry et al. in IEEE Trans Microw Theory Tech 47(11):2075–2084, 1999 ) (circles and squares), triangular split-ring resonators (TSRRs) only allow frequencies near the center resonant frequency to propagate. Further, TSRRs are attractive due to their small surface area (Vidhyalakshmi et al. in Stopband characteristics of complementary triangular split ring resonator loaded microstrip line, 2011 ), comparatively, and large quality factors ( Q ) as previously investigated by Gay-Balmaz et al. (J Appl Phys 92(5):2929–2936, 2002 ). In this work, we examine the effects of varying the apex angle on the resonant frequency, the Q factor, and the phase shift imparted by the TSRR element within the GHz frequency regime.