A metalayer (ML) composed of indium antimonide, ferroelectric crystals, and porous silicon (Psi) with high transmission, sensing properties, wide detecting range, and multiple physical measurements is proposed which is optimized by the improved ant colony algorithm (IACO). Due to the quasi-phase matching principle and nonlinear optical properties, the second harmonic waves (SHWs) with high conversion efficiency are successfully generated in the micrometer operating band and form a high and narrow transmission peak for sensing detection. Through analysis using the transfer matrix method (TMM) which is driven by IACO to accelerate the optimization of structures, the sensing performance sensitivity (S), quality factor (Q), figure of merit (FOM), and detection limit (DL) are calculated. The proposed ML demonstrates the capability to measure thickness ( $S=18.75$ , $Q=11\,\,885$ , FOM = $332\,\,\mu \text{m}^{-1}$ ), external temperature ( $S=4.6$ nm/K, $Q=7046$ , FOM = 0.049 K−1), and magnetic field intensity ( $S=1332$ nm/T, $Q=8146$ , FOM = 16.3 T−1). Additionally, it exhibits an ultrawide refractive index (RI) sensing range from 1 to 5, and excels in detecting hydrobacteria, and viruses with good sensing performance ( $S=44\,\,000$ and 43 460 nm/RIU), high Q values (5585 and 6103), and low DL ( $1.38 \times 10^{-4}$ and $1.3 \times 10^{-4}$ RIU). This versatile and promising ML design offers possibilities for comprehensive multiphysical and chemical parameter measurements in diverse fields.