Performance analysis of DAST material assisted electro-optically tuned Bloch surface wave sensor

Abstract

In this manuscript, a 4-N, N-dimethylamino-4′ -N′ -methyl-stilbazolium tosylate (DAST) material assisted electro-optically tuned Bloch Surface Wave Sensor is proposed. The structure is designed using a one-dimensional photonic crystal (1D-PhC) structure. A top defective layer of DAST as an electro-optic material is used. The analysis shows that by illuminating the device with poly-chromatic light at an incident angle of 45.11◦ results in Bloch mode excitation at a 632.8nm operating wavelength. The analytical results also demonstrate the post fabrication 47 nm BSW wavelength tuning by applying only ±5 V potential. The structure also exhibits both wavelength stability (at varying angle) and angular stability (at varying wavelength). Moreover, the structure exhibits 105.71nm/RIU sensitivity at 0V applied bias voltage having very low FWHM of <1nm. Thus, the proposed design possesses the advantage in terms of low voltage wavelength tuning, stable response, easy fabrication, and integration capability in integrated circuits.