High sensitivity optical detection by temperature independent differential polarization surface plasmon resonance

A method of detecting an amount of change in light intensity caused by surface plasmon resonance comprising:

• coupling light having transverse magnetic and transverse electric polarization modes into a slab waveguide having a metallic film that supports the surface plasmon resonance;
• detecting the transverse magnetic and transverse electric polarized light as it emanates from the slab waveguide;
• and
• determining an instantaneous difference in intensities between the transverse magnetic and transverse electric polarization modes of the emitted light.

A slab waveguide system for detecting an amount of change in light intensity caused by surface plasmon resonance comprising:

• a slab waveguide and a metallic film that support the surface plasmon resonance, wherein the metal film has a thickness that when varied causes a shift in a response curve of the surface plasmon resonance;
• a light source that couples light into the slab waveguide exciting the surface plasmon resonance in the metal film;
• a detector for detecting the light as it emanates from the slab waveguide;
• and
• a processor for determining an intensity of the emanating light.

A slab waveguide system for detecting an amount of change in light intensity caused by surface plasmon resonance comprising:

• a slab waveguide and a metallic film that support the surface plasmon resonance, wherein a substrate of the slab waveguide includes materials having a thermo-optic coefficient that substantially matches to that of a test sample under analysis;
• a light source that couples light into the slab waveguide exciting the surface plasmon resonance in the metal film;
• a detector for detecting light as it emanates from the slab waveguide;
• and
• a processor for determining an intensity of the light.