Photonic crystal bio-sensor for highly sensitive label-free detection of cancer cells

A novel design of bio-sensor based on the silicon photonic crystal double-elliptical ring resonators with improved sensitivity and capability for cancer detection is proposed. According to numerical results, the design obtained simultaneous high sensitivity of 1170 nm/RIU (nm per refractive index unit) and 1116.66 nm/RIU and improved quality factor (Q) of 422.36 and 449.16 for skin (Basal) and cervical (HeLa) cancer cells, respectively. Furthermore, the design proved the detection limit value as low as 3.2 × 10 - 3 RIU . The finite-difference time-domain method is used for the numerical investigation of the proposed structures. The attractive and simple topology of the proposed bio-sensor and its high sensitivity makes it a suitable candidate for bio-sensing applications.