title: Molecular layer detection on a diffractive optical balance.
abstract: Diffraction-based molecular detection is achieved by etching optical gratings into thermal oxide on silicon. The gratings perform as a stable common-path diffractive optical balance (DOB) designed to operate near a missing diffraction order. The biosensor is operated in an off-null condition with a phase bias to produce a high-contrast responsivity that is linear in accumulated molecules but with a low background. The DOB linear responsivity is a factor of 20 larger than the reflectometric responsivity of planar thermal oxide.
authors.affiliation: Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA.
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Wang
authors.forename: Ming
authors.initials: M
authors.lastname: Zhao
authors.forename: David D
authors.initials: DD
authors.lastname: Nolte
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D007074:Immunoglobulin G / Q000737:chemistry / Q000378:metabolism; D007834:Lasers; D055620:Optical Phenomena; D011817:Rabbits; D059629:Signal-To-Noise Ratio; D012825:Silicon / Q000737:chemistry
chemical_list: D007074:Immunoglobulin G; D012825:Silicon