Leveraging THz photonic crystal fibers for sensitive detection of Staphylococcus aureus bacteria

Staphylococcus aureus, commonly referred to as S. aureus, is a type of bacteria that is often found on the skin and in the nasal passages of humans. Staphylococcus aureus is a common but potentially dangerous bacterium, notable for its role in various infections and its capacity for antibiotic resistance. In this situation, our motivation is to develop a photonic crystal fiber detector to detect these deadly gram-positive bacteria. In our study, we achieved a max Relative Sensitivity (RS) of 96.82% and 96.73% on the x and y poles, respectively, at an operating frequency equal to 3.2 THz. We further investigate several kinds of losses, such as loss of confinement (CL) and loss of effective material (EML). We achieve minimal CL that is 3.415 × 10^–5 dB/m and 1.624 × 10^–4 dB/m on the x and y poles, respectively. The lowest EMLs we achieve are 0.0062 cm⁻¹, and 0.0085 cm⁻¹ on the x and y poles, respectively. The small size and flexibility of the suggested PCF sensor make it suitable for miniaturized and portable sensing devices. This portability is advantageous for point-of-care diagnostics and field applications where rapid and on-site detection of Staphylococcus aureus is needed.