Synthesis of Wave Plates Using Multilayered Subwavelength Structure

The form-birefringence effect exhibited in the multilayered subwavelength structure (SWS) has been applied for the realization of wave plates. The SWS was obtained by coating a thin film of a material with a high refractive index onto a base SWS fabricated on a substrate with low refractive index. The multilayer SWS fabricated by this coating process exhibits strong form birefringence compared with that of the base SWS. This fact results in less depth required to realize wave plates than that with only the base SWS. In this study, a quarter-wave plate for the operating wavelength of a He-Ne laser (λ= 632.8 nm) was designed and fabricated using the above described multilayered SWS. The experimental results demonstrated that the fabricated device is effective as a quarter-wave plate and gives transmission efficiencies near 90% for both transverse electric (TE) and transverse magnetic (TM) waves.