title: Nanoscale optical interferometry with incoherent light.
abstract: Optical interferometry has empowered an impressive variety of biosensing and medical imaging techniques. A widely held assumption is that devices based on optical interferometry require coherent light to generate a precise optical signature in response to an analyte. Here we disprove that assumption. By directly embedding light emitters into subwavelength cavities of plasmonic interferometers, we demonstrate coherent generation of surface plasmons even when light with extremely low degrees of spatial and temporal coherence is employed. This surprising finding enables novel sensor designs with cheaper and smaller light sources, and consequently increases accessibility to a variety of analytes, such as biomarkers in physiological fluids, or even airborne nanoparticles. Furthermore, these nanosensors can now be arranged along open detection surfaces, and in dense arrays, accelerating the rate of parallel target screening used in drug discovery, among other high volume and high sensitivity applications.
authors.affiliation: School of Engineering, Brown University, Providence, Rhode Island, 02912, United States.
authors.forename: Dongfang
authors.initials: D
authors.lastname: Li
authors.affiliation: School of Engineering, Brown University, Providence, Rhode Island, 02912, United States.
authors.forename: Jing
authors.initials: J
authors.lastname: Feng
authors.affiliation: School of Engineering, Brown University, Providence, Rhode Island, 02912, United States.
authors.forename: Domenico
authors.initials: D
authors.lastname: Pacifici
mesh_terms: D015374:Biosensing Techniques; D007368:Interferometry; D008027:Light; D020349:Surface Plasmon Resonance