Multispectral plasmonic sensor array for chiral molecule detection

A system for generating a molecular barcode of a chiral active molecule, comprising:

• a multispectral plasmonic sensor comprising:
• a substrate;
• a reflector layer disposed about a top surface of the substrate;
• a dielectric cavity layer disposed about a surface of the reflector layer;
• a pixelated array comprising a plurality of pixels disposed about a surface of the dielectric cavity layer wherein each pixel of the pixelated array comprises a periodic square array of nanoholes;
• a plurality of metallic nano disks disposed above the nanoholes of the pixels of the pixelated array to define hole-disk plasmonic resonators;
• and
• wherein the pixels of the pixelated array are scaled in increments across the array such that each pixel can resonate at a distinct mid-infrared (“mid-IR”) wavelength;
• a light source configured to generate mid-IR circularly polarized light directed towards the pixelated array;
• and
• a detection system communicatively coupled to the pixelated array configured to measure spectral responses of the pixelated array under left-circularly polarized and right-circularly polarized illuminations and compute dissymmetry factors for the pixelated array and assemble the computed dissymmetry factors into a chiral barcode.

A method for detecting and characterizing chiral active molecules, the method comprising:

• providing a system for generating a molecular barcode of a chiral active molecule, the system comprising:
• a multispectral plasmonic sensor;
• a light source configured to generate mid-IR circularly polarized light directed towards the pixelated array;
• and
• a detection system communicatively coupled to the pixelated array configured to measure spectral responses of the pixelated array under left-circularly polarized and right-circularly polarized illuminations and compute dissymmetry factors for the pixelated array and assemble the computed dissymmetry factors into a chiral barcode;
• illuminating the multispectral plasmonic sensor with circularly polarized light to generate enhanced electric and magnetic near fields at each pixel of the pixelated array of the plasmonic sensor;
• introducing a chiral active molecule onto the surface of the pixelated array of the multispectral plasmonic sensor;
• measuring, via the detection system, the differential absorption of left-circularity and right-circularly polarized light;
• computing, via the detection system, dissymmetry factors for each pixel of the pixelated array based on the measured spectral responses;
• and
• assembling, via the detection system, the dissymmetry factors into a barcode representing a molecularly unique chiral signature of the introduced chiral active molecule.