Boltasseva, A. et al. Integrated optical components utilizing long-range surface plasmon polaritons. J. Lightwave Technol. 23, 413-422

Res. Center COM, Tech. Univ. of Denmark, Lyngby, Denmark
Journal of Lightwave Technology (Impact Factor: 2.97). 02/2005; 23(1):413 - 422. DOI: 10.1109/JLT.2004.835749
Source: IEEE Xplore


New optical waveguide technology for integrated optics, based on propagation of long-range surface plasmon polaritons (LR-SPPs) along metal stripes embedded in dielectric, is presented. Guiding and routing of electromagnetic radiation along nanometer-thin and micrometer-wide gold stripes embedded in polymer via excitation of LR-SPPs is investigated in the wavelength range of 1250-1650 nm. LR-SPP guiding properties, such as the propagation loss and mode-field diameter, are investigated for different stripe widths and thicknesses. A propagation loss of /spl sim/6 dB/cm, a coupling loss of /spl sim/0.5 dB (per facet), and a bend loss of /spl sim/5 dB for a bend radius of 15 mm are evaluated for 15-nm-thick and 8-/spl mu/m-wide stripes at the wavelength of 1550 nm. LR-SPP-based 3-dB power Y-splitters, multimode interference waveguides, and directional couplers are demonstrated and investigated. At 1570 nm, coupling lengths of 1.9 and 0.8 mm are found for directional couplers with, respectively, 4- and 0-/spl mu/m-separated waveguides formed by 15-nm-thick and 8-/spl mu/m-wide gold stripes. LR-SPP-based waveguides and waveguide components are modeled using the effective-refractive-index method, and good agreement with experimental results is obtained.

Full-text preview

Available from:
  • Source
    • "LRSPPs are confined to the waveguide in the plane transverse to the direction of propagation making it possible to construct various integrated circuits such as Y-junctions, S-bends and Mach–Zehnder Interferometers (MZIs) [19], [20]. Au MZIs embedded in CYTOP with one arm etched to create a microfluidic channel have been successfully tested for RI changes in solution [21]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The design and optimization of straight long-range surface plasmon waveguides to maximize attenuation surface sensitivity in biochemical sensing applications is discussed. The sensor consists of a Au stripe embedded in CYTOP, with a microfluidic channel etched into the top cladding to expose the surface of the Au stripe and define the sensing channel. The attenuation αs of the structure changes as a biological adlayer grows on the Au surface. The dimensions of the stripe (thickness, width), the sensing length and the refractive index of the sensing buffer were varied in order to understand their impact on sensor performance. The attenuation sensitivity ∂αs/∂a dominates over a wide range of waveguide designs, so we define a parameter K= (∂αs/∂a)/αswhere maximizing |K| and selecting the optimal sensing length as Lopt = 1/(2αs) maximizes the overall sensitivity of the structure. Experimental results based on observing the physisorption of bovine serum albumin (BSA) on bare Au waveguides agree qualitatively and quantitatively with theory. Detection limits of ΔΓmin < 0.1 pg mm-2 are predicted for optimal designs, and a detection limit of ΔΓmin = 4.1 pg/mm2 (SNR = 1) is demonstrated experimentally for a sub-optimal structure.
    Journal of Lightwave Technology 08/2015; 33(15):1-1. DOI:10.1109/JLT.2015.2431612 · 2.97 Impact Factor
  • Source
    • "Different types of waveguides have been proposed and investigated for their ability to guide optical waves with subwavelength cross sectional mode dimensions [3] [4] [5] [6] [7] [8] [9] [10] [11]. Based on these waveguides, several passive and active devices and elements such as bends, interferometers, filters, resonators, and lasers have been demonstrated [12] [13] [14] [15]. Although waveguides with subwavelength mode dimensions such as coaxial and microstrip lines are widely used at millimeter wave, microwave and lower frequencies without a significant loss, at higher frequencies metal absorption loss has been an obstacle for plasmonic waveguides to find practical applications. "
    [Show abstract] [Hide abstract]
    ABSTRACT: A fundamental trade-off relation between the cross sectional confinement and propagation length of an arbitrary mode of a general waveguide is presented. This limit is a generalization of the well-known diffraction limit for guided modes. The results provide a lower bound on propagation loss of plasmonic waveguides which are attractive for their deep subwavelength mode dimensions. We also introduce a material loss merit factor that sets a criterion for comparing different plasmonic materials for achieving the best trade-off between confinement and loss.
  • Source
    • "To date, several different types of LR-SPP waveguiding configuration have been proposed and demonstrated, which include the traditional LR-SPP waveguides that consist of metal stripes embedded in a homogeneous dielectric [9] [10] [11], and modified LR-SPP structures incorporating additional dielectric layers on both sides of the metallic layers [12] [13] [14] [15] or comprising metal stripes embedded in high-index dielectrics [16] [17] [18]. Moreover, several other types of longrange plasmonic structure have also been proposed recently, such as the long-range dielectric-loaded SPP waveguides (LR-DLSPPWs) [19] [20] [21] and long-range channel plasmon polariton waveguides (LR-CPPWs) [22]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The characteristics of long-range hybrid plasmonic modes guided by multilayer metal-dielectric planar waveguides are investigated at the telecom wavelength. These multilayer structures are formed by sandwiching thin metallic stripes into horizontal silicon slot-like waveguides. Comprehensive numerical studies regarding the geometric parameters' effects on the modal properties reveal that, by properly choosing the dimensions of the metal stripe and the low-index gaps between the stripe and the silicon layers, the symmetric hybrid modes supported by the structures could feature simultaneously ultra-long propagation distance (several centimeters) and subwavelength mode size. Consideration of possible fabrication imperfections shows that the optical performances of the waveguides are quite robust and highly tolerant to these errors. The presented multilayer plasmonic structures greatly extend the capabilities of conventional long-range surface plasmon polariton waveguides by successfully confining light into a subwavelength scale while maintaining the key advantage of enabling ultra-low-loss propagation, which could facilitate potential applications in ultra-long-range plasmon waveguiding and realizations of compact, high-performance photonic components, as well as building optically integrated circuits with complex functionalities.
    Journal of optics 01/2014; 16(1-1). DOI:10.1088/2040-8978/16/1/015001 · 2.06 Impact Factor
Show more