title: Surface plasmon-enhanced nanopillar photodetectors.
abstract: We demonstrate nanopillar-(NP) based plasmon-enhanced photodetectors (NP-PEPDs) operating in the near-infrared spectral regime. A novel fabrication technique produces subwavelength elongated nanoholes in a metal surface self-aligned to patterned NP arrays that acts as a 2D plasmonic crystal. Surface plasmon Polariton Bloch waves (SPP-BWs) are excited by the metal nanohole array resulting in electric field intensity "hot spots" in the NP. The NP periodicity determines the peak responsivity wavelength while the nanohole asymmetry produces polarization-dependent coupling of the SPP-BW modes. Resulting photodetectors have 0.28 A/W responsivity peaked at 1100 nm at a reverse bias of -5 V. Designs for further increasing the optical coupling efficiency into the nanopillar are explored. This technology has potential applications for plasmonically enhanced focal plane arrays and plasmonic photovoltaics.
authors.affiliation: Department of Electrical Engineering and California Nano-Systems Institute, University of California Los Angeles, Los Angeles, California 90095, United States. pradeeps@ee.ucla.edu
authors.forename: Pradeep
authors.initials: P
authors.lastname: Senanayake
authors.forename: Chung-Hong
authors.initials: CH
authors.lastname: Hung
authors.forename: Joshua
authors.initials: J
authors.lastname: Shapiro
authors.forename: Andrew
authors.initials: A
authors.lastname: Lin
authors.forename: Baolai
authors.initials: B
authors.lastname: Liang
authors.forename: Benjamin S
authors.initials: BS
authors.lastname: Williams
authors.forename: D L
authors.initials: DL
authors.lastname: Huffaker