Abstract: Methods and apparatuses for mode conversion. An apparatus that includes a substrate, a first waveguide, a second waveguide, a micro-electro-mechanical systems (MEMS) perturber, and a controller is provided. The first waveguide is formed on the substrate includes: (i) an input section, (ii) a bend section, and (iii) an output section. The second waveguide is also formed on the substrate and is disposed adjacent to a portion of the input section of the first waveguide. A portion of the second waveguide is separated from the input section of the first waveguide by a coupling gap. The perturber is disposed above the first waveguide and configured to move between a first position that is distal from a surface of the input section of the first waveguide and a second position that is closer to the surface of the input section of the first waveguide than the second position. The controller is configured to control a movement of the perturber between the first position and the second position.

Abstract: Methods and apparatuses for mode conversion. An apparatus that includes a substrate, a first waveguide, a second waveguide, a micro-electro-mechanical systems (MEMS) perturber, and a controller is provided. The first waveguide is formed on the substrate includes: (i) an input section, (ii) a bend section, and (iii) an output section. The second waveguide is also formed on the substrate and is disposed adjacent to a portion of the input section of the first waveguide. A portion of the second waveguide is separated from the input section of the first waveguide by a coupling gap. The perturber is disposed above the first waveguide and configured to move between a first position that is distal from a surface of the input section of the first waveguide and a second position that is closer to the surface of the input section of the first waveguide than the second position. The controller is configured to control a movement of the perturber between the first position and the second position.

Abstract: A system and method for detecting an analyte includes a waveguide configured to receive a narrow-band laser signal; and a sorbent material covering an analyte detection region of the waveguide, wherein the sorbent material is configured to sorb the analyte and bring the analyte to an evanescent field of the waveguide, and wherein Raman scattering is produced by an interaction of the evanescent field and the analyte sorbed in the sorbent material along the analyte detection region of the waveguide, and the waveguide is further configured to collect the Raman scattering along the analyte detection region of the waveguide, wherein the collected Raman scattering indicates a type of the analyte.

Abstract: A system and method for detecting an analyte includes a waveguide configured to receive a narrow-band laser signal; and a sorbent material covering an analyte detection region of the waveguide, wherein the sorbent material is configured to sorb the analyte and bring the analyte to an evanescent field of the waveguide, and wherein Raman scattering is produced by an interaction of the evanescent field and the analyte sorbed in the sorbent material along the analyte detection region of the waveguide, and the waveguide is further configured to collect the Raman scattering along the analyte detection region of the waveguide, wherein the collected Raman scattering indicates a type of the analyte.