201
|
Abstract
The recently emerging three-dimensional (3D) displays in the electronic shops imitate depth illusion by overlapping two parallax 2D images through either polarized glasses that viewers are required to wear or lenticular lenses fixed directly on the display. Holography, on the other hand, provides real 3D imaging, although usually limiting colors to monochrome. The so-called rainbow holograms--mounted, for example, on credit cards--are also produced from parallax images that change color with viewing angle. We report on a holographic technique based on surface plasmons that can reconstruct true 3D color images, where the colors are reconstructed by satisfying resonance conditions of surface plasmon polaritons for individual wavelengths. Such real 3D color images can be viewed from any angle, just like the original object.
Collapse
|
202
|
Giannini V, Fernández-Domínguez AI, Heck SC, Maier SA. Plasmonic Nanoantennas: Fundamentals and Their Use in Controlling the Radiative Properties of Nanoemitters. Chem Rev 2011; 111:3888-912. [DOI: 10.1021/cr1002672] [Citation(s) in RCA: 1067] [Impact Index Per Article: 82.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Vincenzo Giannini
- Department of Physics, Imperial College London, London SW7 2AZ, United Kingdom
| | | | - Susannah C. Heck
- Department of Physics, Imperial College London, London SW7 2AZ, United Kingdom
| | - Stefan A. Maier
- Department of Physics, Imperial College London, London SW7 2AZ, United Kingdom
| |
Collapse
|
203
|
Tajdini MM, Mosallaei H. Characterization of large array of plasmonic nanoparticles on layered substrate: dipole mode analysis integrated with complex image method. OPTICS EXPRESS 2011; 19 Suppl 2:A173-A193. [PMID: 21445219 DOI: 10.1364/oe.19.00a173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this paper, an efficient analytical method for characterizing large array of plasmonic nanoparticles located over planarly layered substrate is introduced. The model is called dipole mode complex image (DMCI) method since the main idea lies in modeling a subwavelength spherical nanoparticle at its electric scattering resonance with an induced electric dipole and representing the electromagnetic (EM) fields of this electric dipole over the layered substrate in terms of finite complex images. The major advantages of the proposed method are its accuracy and rapid calculation in characterizing various kinds of large periodic and aperiodic arrays of nanoparticles on layered substrates. The computational time can be reduced significantly in compared to the traditional methods. The accuracy of the theoretical model is validated through comparison with numerical integration of Sommerfeld integrals. Moreover, the analytical results are compared well with those determined by full-wave finite difference time domain (FDTD) method. To demonstrate the capability of our technique, the performances of large arrays of nanoparticles on layered silicon substrates for efficient sunlight energy incoupling are studied.
Collapse
Affiliation(s)
- Mohammad Mahdi Tajdini
- Applied EM and Optics Laboratory, Northeastern University, 360 Huntington Ave, Boston, Massachusetts 02115, USA.
| | | |
Collapse
|
204
|
High photoelectric conversion efficiency of metal phthalocyanine/fullerene heterojunction photovoltaic device. Int J Mol Sci 2011; 12:476-505. [PMID: 21339999 PMCID: PMC3039965 DOI: 10.3390/ijms12010476] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2010] [Revised: 12/27/2010] [Accepted: 01/06/2011] [Indexed: 11/16/2022] Open
Abstract
This paper introduces the fundamental physical characteristics of organic photovoltaic (OPV) devices. Photoelectric conversion efficiency is crucial to the evaluation of quality in OPV devices, and enhancing efficiency has been spurring on researchers to seek alternatives to this problem. In this paper, we focus on organic photovoltaic (OPV) devices and review several approaches to enhance the energy conversion efficiency of small molecular heterojunction OPV devices based on an optimal metal-phthalocyanine/fullerene (C60) planar heterojunction thin film structure. For the sake of discussion, these mechanisms have been divided into electrical and optical sections: (1) Electrical: Modification on electrodes or active regions to benefit carrier injection, charge transport and exciton dissociation; (2) Optical: Optional architectures or infilling to promote photon confinement and enhance absorption.
Collapse
|
205
|
Ferry VE, Munday JN, Atwater HA. Design considerations for plasmonic photovoltaics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2010; 22:4794-808. [PMID: 20814916 DOI: 10.1002/adma.201000488] [Citation(s) in RCA: 219] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
This paper reviews the recent research progress in the incorporation of plasmonic nanostructures with photovoltaic devices and the potential for surface plasmon enhanced absorption. We first outline a variety of cell architectures incorporating metal nanostructures. We then review the experimental fabrication methods and measurements to date, as well as systematic theoretical studies of the optimal nanostructure shapes. Finally we discuss photovoltaic absorber materials that could benefit from surface plasmon enhanced absorption.
Collapse
Affiliation(s)
- Vivian E Ferry
- Thomas J. Watson Laboratories of Applied Physics, California Institute of Technology, Pasadena, California 91125, USA
| | | | | |
Collapse
|
206
|
Bai W, Gan Q, Song G, Chen L, Kafafi Z, Bartoli F. Broadband short-range surface plasmon structures for absorption enhancement in organic photovoltaics. OPTICS EXPRESS 2010; 18 Suppl 4:A620-A630. [PMID: 21165095 DOI: 10.1364/oe.18.00a620] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We theoretically demonstrate a polarization-independent nanopatterned ultra-thin metallic structure supporting short-range surface plasmon polariton (SRSPP) modes to improve the performance of organic solar cells. The physical mechanism and the mode distribution of the SRSPP excited in the cell device were analyzed, and reveal that the SRSPP-assisted broadband absorption enhancement peak could be tuned by tailoring the parameters of the nanopatterned metallic structure. Three-dimensional finite-difference time domain calculations show that this plasmonic structure can enhance the optical absorption of polymer-based photovoltaics by 39% to 112%, depending on the nature of the active layer (corresponding to an enhancement in short-circuit current density by 47% to 130%). These results are promising for the design of organic photovoltaics with enhanced performance.
Collapse
Affiliation(s)
- Wenli Bai
- Electrical and Computer Engineering Department, Lehigh University, Bethlehem, PA 18015, USA
| | | | | | | | | | | |
Collapse
|
207
|
Halas NJ. Plasmonics: an emerging field fostered by Nano Letters. NANO LETTERS 2010; 10:3816-22. [PMID: 20853888 DOI: 10.1021/nl1032342] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
While studies of surface plasmons on metals have been pursued for decades, the more recent appearance of nanoscience has created a revolution in this field with "Plasmonics" emerging as a major area of research. The direct optical excitation of surface plasmons on metallic nanostructures provides numerous ways to control and manipulate light at nanoscale dimensions. This has stimulated the development of novel optical materials, deeper theoretical insight, innovative new devices, and applications with potential for significant technological and societal impact. Nano Letters has been instrumental in the emergence of plasmonics, providing its readership with rapid advances in this dynamic field.
Collapse
Affiliation(s)
- Naomi J Halas
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, Texas 77005-1892, USA.
| |
Collapse
|
208
|
|
209
|
Yu Z, Raman A, Fan S. Fundamental limit of light trapping in grating structures. OPTICS EXPRESS 2010; 18 Suppl 3:A366-80. [PMID: 21165067 DOI: 10.1364/oe.18.00a366] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We use a rigorous electromagnetic approach to analyze the fundamental limit of light-trapping enhancement in grating structures. This limit can exceed the bulk limit of 4n², but has significant angular dependency. We explicitly show that 2D gratings provide more enhancement than 1D gratings. We also show the effects of the grating profile's symmetry on the absorption enhancement limit. Numerical simulations are applied to support the theory. Our findings provide general guidance for the design of grating structures for light-trapping solar cells.
Collapse
|
210
|
Ranjan M, Oates TWH, Facsko S, Möller W. Optical properties of silver nanowire arrays with 35 nm periodicity. OPTICS LETTERS 2010; 35:2576-2578. [PMID: 20680063 DOI: 10.1364/ol.35.002576] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We present highly ordered Ag nanowire arrays with 35nm periodicity grown on patterned templates. The optical properties measured using generalized ellipsometry exhibit strong anisotropy. Dielectric functions are calculated by fitting the Jones matrix elements with a biaxial layer model, accounting for both metallic behavior and localized surface plasmon resonances. The amplitude and wavelength maximum of the plasmon resonance perpendicular to the wires increase with increasing wire width and thickness. The dielectric coefficients of 10-mm-wide nanowires show a transition behavior from insulating in UV to metallic above 550nm. Their potential application as polarization-dependent plasmonic-scattering transparent conductive electrodes is discussed.
Collapse
Affiliation(s)
- Mukesh Ranjan
- Institute of Ion Beam Physics and Materials Research, Forschungszentrum Dresden-Rossendorf e.V.,P.O. Box 510119, 01314 Dresden, Germany
| | | | | | | |
Collapse
|
211
|
Tseng HY, Lee CK, Wu SY, Chi TT, Yang KM, Wang JY, Kiang YW, Yang CC, Tsai MT, Wu YC, Chou HYE, Chiang CP. Au nanorings for enhancing absorption and backscattering monitored with optical coherence tomography. NANOTECHNOLOGY 2010; 21:295102. [PMID: 20601768 DOI: 10.1088/0957-4484/21/29/295102] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Preparation of a high-concentration Au nanoring (NR) water solution and its applications to the enhancement of image contrast in optical coherence tomography (OCT) and the generation of the photothermal effect in a bio-sample through localized surface plasmon (LSP) resonance are demonstrated. Au NRs are first fabricated on a sapphire substrate with colloidal lithography and secondary sputtering of Au, and then transferred into a water solution through a liftoff process. By controlling the NR geometry, the LSP dipole resonance wavelength in tissue can cover a spectral range of 1300 nm for OCT scanning of deep tissue penetration. The extinction cross sections of the fabricated Au NRs in water are estimated to give levels of 10(-10)-10(-9) cm(2) near their LSP resonance wavelengths. The fabricated Au NRs are then delivered into pig adipose samples for OCT scanning. It is observed that, when resonant Au NRs are delivered into such a sample, LSP resonance-induced Au NR absorption results in a photothermal effect, making the opaque pig adipose cells transparent. Also, the delivered Au NRs in the intercellular substance enhance the image contrast of OCT scanning through LSP resonance-enhanced scattering. By continuously OCT scanning a sample, both photothermal and image contrast enhancement effects are observed. However, by continually scanning a sample with a low scan frequency, only the image contrast enhancement effect is observed.
Collapse
Affiliation(s)
- Hung-Yu Tseng
- Institute of Photonics and Optoelectronics, and Department of Electrical Engineering, National Taiwan University, No 1, Section 4, Roosevelt Road, Taipei 10617, Taiwan, Republic of China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
212
|
Ferry VE, Verschuuren MA, Li HBT, Verhagen E, Walters RJ, Schropp REI, Atwater HA, Polman A. Light trapping in ultrathin plasmonic solar cells. OPTICS EXPRESS 2010; 18 Suppl 2:A237-45. [PMID: 20588593 DOI: 10.1364/oe.18.00a237] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We report on the design, fabrication, and measurement of ultrathin film a-Si:H solar cells with nanostructured plasmonic back contacts, which demonstrate enhanced short circuit current densities compared to cells having flat or randomly textured back contacts. The primary photocurrent enhancement occurs in the spectral range from 550 nm to 800 nm. We use angle-resolved photocurrent spectroscopy to confirm that the enhanced absorption is due to coupling to guided modes supported by the cell. Full-field electromagnetic simulation of the absorption in the active a-Si:H layer agrees well with the experimental results. Furthermore, the nanopatterns were fabricated via an inexpensive, scalable, and precise nanopatterning method. These results should guide design of optimized, non-random nanostructured back reflectors for thin film solar cells.
Collapse
Affiliation(s)
- Vivian E Ferry
- Center for Nanophotonics, FOM Institute AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands.
| | | | | | | | | | | | | | | |
Collapse
|
213
|
Tsai FJ, Wang JY, Huang JJ, Kiang YW, Yang CC. Absorption enhancement of an amorphous Si solar cell through surface plasmon-induced scattering with metal nanoparticles. OPTICS EXPRESS 2010; 18 Suppl 2:A207-A220. [PMID: 20588590 DOI: 10.1364/oe.18.00a207] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The simulation results of absorption enhancement in an amorphous-Si (a-Si) solar cell by depositing metal nanoparticles (NPs) on the device top and embedding metal NPs in a layer above the Al back-reflector are demonstrated. The absorption increase results from the near-field constructive interference of electromagnetic waves in the forward direction such that an increased amount of sunlight energy is distributed in the a-Si absorption layer. Among the three used metals of Al, Ag, and Au, Al NPs show the most efficient absorption enhancement. Between the two used NP geometries, Al nanocylinder (NC) are more effective in absorption enhancement than Al nanosphere (NS). Also, a random distribution of isolated metal NCs can lead to higher absorption enhancement, when compared with the cases of periodical metal NC distributions. Meanwhile, the fabrication of both top and bottom Al NCs in a solar cell results in further absorption enhancement. Misalignments between the top and bottom Al NCs do not significantly reduce the enhancement percentage. With a structure of vertically aligned top and bottom Al NCs, solar cell absorption can be increased by 52%.
Collapse
Affiliation(s)
- Fu-Ji Tsai
- Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, No. 1 Roosevelt Road, Section 4, Taipei 10617, Taiwan
| | | | | | | | | |
Collapse
|
214
|
Zhu J, Hsu CM, Yu Z, Fan S, Cui Y. Nanodome solar cells with efficient light management and self-cleaning. NANO LETTERS 2010; 10:1979-84. [PMID: 19891462 DOI: 10.1021/nl9034237] [Citation(s) in RCA: 150] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Here for the first time, we demonstrate novel nanodome solar cells, which have periodic nanoscale modulation for all layers from the bottom substrate, through the active absorber to the top transparent contact. These devices combine many nanophotonic effects to both efficiently reduce reflection and enhance absorption over a broad spectral range. Nanodome solar cells with only a 280 nm thick hydrogenated amorphous silicon (a-Si:H) layer can absorb 94% of the light with wavelengths of 400-800 nm, significantly higher than the 65% absorption of flat film devices. Because of the nearly complete absorption, a very large short-circuit current of 17.5 mA/cm(2) is achieved in our nanodome devices. Excitingly, the light management effects remain efficient over a wide range of incident angles, favorable for real environments with significant diffuse sunlight. We demonstrate nanodome devices with a power efficiency of 5.9%, which is 25% higher than the flat film control. The nanodome structure is not in principle limited to any specific material system and its fabrication is compatible with most solar manufacturing; hence it opens up exciting opportunities for a variety of photovoltaic devices to further improve performance, reduce materials usage, and relieve elemental abundance limitations. Lastly, our nanodome devices when modified with hydrophobic molecules present a nearly superhydrophobic surface and thus enable self-cleaning solar cells.
Collapse
Affiliation(s)
- Jia Zhu
- Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA
| | | | | | | | | |
Collapse
|
215
|
Wang W, Wu S, Reinhardt K, Lu Y, Chen S. Broadband light absorption enhancement in thin-film silicon solar cells. NANO LETTERS 2010; 10:2012-8. [PMID: 20446722 DOI: 10.1021/nl904057p] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Currently, the performances of thin film solar cells are limited by poor light absorption and carrier collection. In this research, large, broadband, and polarization-insensitive light absorption enhancement was realized via integrating with unique metallic nanogratings. Through simulation, three possible mechanisms were identified to be responsible for such an enormous enhancement. A test for totaling the absorption over the solar spectrum shows an up to approximately 30% broadband absorption enhancement when comparing to bare thin film cells.
Collapse
Affiliation(s)
- Wei Wang
- Materials Science and Engineering, The University of Texas at Austin, Austin, Texas 78712, USA
| | | | | | | | | |
Collapse
|
216
|
Konstantatos G, Sargent EH. Nanostructured materials for photon detection. NATURE NANOTECHNOLOGY 2010; 5:391-400. [PMID: 20473301 DOI: 10.1038/nnano.2010.78] [Citation(s) in RCA: 515] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The detection of photons underpins imaging, spectroscopy, fibre-optic communications and time-gated distance measurements. Nanostructured materials are attractive for detection applications because they can be integrated with conventional silicon electronics and flexible, large-area substrates, and can be processed from the solution phase using established techniques such as spin casting, spray coating and layer-by-layer deposition. In addition, their performance has improved rapidly in recent years. Here we review progress in light sensing using nanostructured materials, focusing on solution-processed materials such as colloidal quantum dots and metal nanoparticles. These devices exhibit phenomena such as absorption of ultraviolet light, plasmonic enhancement of absorption, size-based spectral tuning, multiexciton generation, and charge carrier storage in surface and interface traps.
Collapse
Affiliation(s)
- Gerasimos Konstantatos
- Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ontario M5S 3G4, Canada
| | | |
Collapse
|
217
|
Efficiently Harvesting Sun Light for Silicon Solar Cells through Advanced Optical Couplers and A Radial p-n Junction Structure. ENERGIES 2010. [DOI: 10.3390/en3040784] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
218
|
Kofke MJ, Waldeck DH, Walker GC. Composite nanoparticle nanoslit arrays: a novel platform for LSPR mediated subwavelength optical transmission. OPTICS EXPRESS 2010; 18:7705-7713. [PMID: 20588611 DOI: 10.1364/oe.18.007705] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Near infrared transmission of light through subwavelength slit arrays is shown to be significantly influenced by resonant metallic nanoparticles placed within the structure. Experimental and calculated transmission spectra show how the size, orientation of the nanoparticles, and the period of the nanoslit array influence the maximum transmission wavelength, the magnitude of the transmission, and width of the resonance. These findings suggest that the localized surface plasmon resonance (LSPR) of metallic nanoparticles and their subsequent near and far-field interactions can modulate the subwavelength transmission and bandwidth of nanoaperture array devices in optically thick metal films.
Collapse
Affiliation(s)
- Matthew J Kofke
- Department of Chemistry, University of Pittsburgh, 219 Parkman Street, Pittsburgh PA 15260 USA
| | | | | |
Collapse
|
219
|
Koller DM, Hohenester U, Hohenau A, Ditlbacher H, Reil F, Galler N, Aussenegg FR, Leitner A, Trügler A, Krenn JR. Superresolution Moiré mapping of particle plasmon modes. PHYSICAL REVIEW LETTERS 2010; 104:143901. [PMID: 20481940 DOI: 10.1103/physrevlett.104.143901] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2009] [Revised: 03/21/2010] [Indexed: 05/29/2023]
Abstract
The spontaneous emission rate of a fluorophore provides a direct probe of the photonic local density of states at the fluorophore position. Here we exploit this capability to map the plasmonic modes of gold nanoparticles by imaging the fluorescence intensity in combined regular arrays of identical gold and fluorophore-doped polymer nanoparticles. By varying the distance between gold and polymer particles across the array, the fluorophore emission generates an optical Moiré pattern corresponding to a magnified spatial map of the plasmonic mode, which can be directly imaged with an optical microscope. Our results are corroborated by supplementary theoretical model calculations.
Collapse
Affiliation(s)
- D M Koller
- Institute of Physics and Erwin Schrödinger Institute for Nanoscale Research, Karl-Franzens-University, A-8010 Graz, Austria
| | | | | | | | | | | | | | | | | | | |
Collapse
|
220
|
Qiu Y, Chen W, Yang S. Double-Layered Photoanodes from Variable-Size Anatase TiO2 Nanospindles: A Candidate for High-Efficiency Dye-Sensitized Solar Cells. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.200906933] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
221
|
Qiu Y, Chen W, Yang S. Double-Layered Photoanodes from Variable-Size Anatase TiO2 Nanospindles: A Candidate for High-Efficiency Dye-Sensitized Solar Cells. Angew Chem Int Ed Engl 2010; 49:3675-9. [DOI: 10.1002/anie.200906933] [Citation(s) in RCA: 153] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
222
|
Sha WEI, Choy WCH, Chew WC. A comprehensive study for the plasmonic thin-film solar cell with periodic structure. OPTICS EXPRESS 2010; 18:5993-6007. [PMID: 20389619 DOI: 10.1364/oe.18.005993] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A comprehensive study of the plasmonic thin-film solar cell with the periodic strip structure is presented in this paper. The finite-difference frequency-domain method is employed to discretize the inhomogeneous wave function for modeling the solar cell. In particular, the hybrid absorbing boundary condition and the one-sided difference scheme are adopted. The parameter extraction methods for the zeroth-order reflectance and the absorbed power density are also discussed, which is important for testing and optimizing the solar cell design. For the numerical results, the physics of the absorption peaks of the amorphous silicon thin-film solar cell are explained by electromagnetic theory; these peaks correspond to the waveguide mode, Floquet mode, surface plasmon resonance, and the constructively interference between adjacent metal strips. The work is therefore important for the theoretical study and optimized design of the plasmonic thin-film solar cell.
Collapse
Affiliation(s)
- Wei E I Sha
- Department of Electrical and Electronic Engineering, the University of Hong Kong, Pokfulam Road, Hong Kong, China
| | | | | |
Collapse
|
223
|
Han SE, Chen G. Optical absorption enhancement in silicon nanohole arrays for solar photovoltaics. NANO LETTERS 2010; 10:1012-5. [PMID: 20141156 DOI: 10.1021/nl904187m] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We investigate silicon nanohole arrays as light absorbing structures for solar photovoltaics via simulation. To obtain the same ultimate efficiency as a standard 300 microm crystalline silicon wafer, we find that nanohole arrays require twelve times less silicon by mass. Moreover, our calculations show that nanohole arrays have an efficiency superior to nanorod arrays for practical thicknesses. With well-established fabrication techniques, nanohole arrays have great potential for efficient solar photovoltaics.
Collapse
Affiliation(s)
- Sang Eon Han
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | | |
Collapse
|
224
|
Adato R, Yanik AA, Wu CH, Shvets G, Altug H. Radiative engineering of plasmon lifetimes in embedded nanoantenna arrays. OPTICS EXPRESS 2010; 18:4526-37. [PMID: 20389465 DOI: 10.1364/oe.18.004526] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
It is generally accepted that the lifetimes of the localized plasmonic excitations are inherently controlled by the type of the metals and the shape of the nanoparticles. However, extended plasmonic lifetimes and enhanced near-fields in nanoparticle arrays can be achieved as a result of collective excitation of plasmons. In this article, we demonstrate significantly longer plasmon lifetimes and stronger near-field enhancements by embedding the nanoantenna arrays into the substrate. Our approach offers a more homogeneous dielectric background allowing stronger diffractive couplings among plasmonic particles leading to strong suppression of the radiative damping. We observe near-field enhancements well beyond than those achievable with isolated nanoparticles. Enhanced fields obtained in these structures could be attractive for biosensing and non-linear photonics applications.
Collapse
Affiliation(s)
- Ronen Adato
- Department of Electrical and Computer Engineering, Boston University, Boston, MA, 02215, USA
| | | | | | | | | |
Collapse
|
225
|
Atwater HA, Polman A. Plasmonics for improved photovoltaic devices. NATURE MATERIALS 2010; 9:205-13. [PMID: 20168344 DOI: 10.1038/nmat2629] [Citation(s) in RCA: 2724] [Impact Index Per Article: 194.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The emerging field of plasmonics has yielded methods for guiding and localizing light at the nanoscale, well below the scale of the wavelength of light in free space. Now plasmonics researchers are turning their attention to photovoltaics, where design approaches based on plasmonics can be used to improve absorption in photovoltaic devices, permitting a considerable reduction in the physical thickness of solar photovoltaic absorber layers, and yielding new options for solar-cell design. In this review, we survey recent advances at the intersection of plasmonics and photovoltaics and offer an outlook on the future of solar cells based on these principles.
Collapse
Affiliation(s)
- Harry A Atwater
- Caltech Center for Sustainable Energy Research and Thomas J. Watson Laboratories of Applied Physics, California Institute of Technology, Pasadena, California 91125, USA.
| | | |
Collapse
|
226
|
Im H, Lindquist NC, Lesuffleur A, Oh SH. Atomic layer deposition of dielectric overlayers for enhancing the optical properties and chemical stability of plasmonic nanoholes. ACS NANO 2010; 4:947-54. [PMID: 20131870 DOI: 10.1021/nn901842r] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Fabricating plasmonic nanostructures with robust optical and chemical properties remains a challenging task, especially with silver, which has superior optical properties but poor environmental stability. In this work, conformal atomic layer deposition (ALD) of thin alumina overlayers is used to precisely tune the optical transmission properties of periodic nanohole arrays made in gold and silver films. Experiments and computer simulations confirm that ALD overlayers with optimized thicknesses tune and enhance the transmitted intensity due to refractive index matching effects and by modifying the dielectric properties of each nanohole. Furthermore, encapsulating silver nanohole arrays with thin alumina overlayers protects the patterned surfaces against unwanted oxidation and contamination. The ability to precisely tune the optical properties while simultaneously providing robust chemical stability can benefit a broad range of applications, including biosensing and fluorescence imaging.
Collapse
Affiliation(s)
- Hyungsoon Im
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | | | | | | |
Collapse
|
227
|
Zhou W, Gao H, Odom TW. Toward broadband plasmonics: tuning dispersion in rhombic plasmonic crystals. ACS NANO 2010; 4:1241-1247. [PMID: 20078118 DOI: 10.1021/nn901590p] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The angle-dependent optical properties of rhombic plasmonic crystals are described. We show that by extending the capabilities of soft interference lithography, subwavelength periodic patterns with arbitrary 2D Bravais lattices can be generated. In addition, we demonstrate that by lowering the plasmonic crystal lattice symmetry, degenerate conditions can be lifted and more plasmon bands can be excited within a fixed wavelength range. Degeneracies were also removed by changing the polar and azimuthal angles of excitation and visualized in dispersion diagrams. Anticrossings between different plasmon bands were observed to depend significantly on the local refractive index and the excitation direction.
Collapse
Affiliation(s)
- Wei Zhou
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208-3113, USA
| | | | | |
Collapse
|
228
|
Albaladejo S, Gómez-Medina R, Froufe-Pérez LS, Marinchio H, Carminati R, Torrado JF, Armelles G, García-Martín A, Sáenz JJ. Radiative corrections to the polarizability tensor of an electrically small anisotropic dielectric particle. OPTICS EXPRESS 2010; 18:3556-3567. [PMID: 20389364 DOI: 10.1364/oe.18.003556] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Radiative corrections to the polarizability tensor of isotropic particles are fundamental to understand the energy balance between absorption and scattering processes. Equivalent radiative corrections for anisotropic particles are not well known. Assuming that the polarization within the particle is uniform, we derived a closed-form expression for the polarizability tensor which includes radiative corrections. In the absence of absorption, this expression of the polarizability tensor is consistent with the optical theorem. An analogous result for infinitely long cylinders was also derived. Magneto optical Kerr effects in non-absorbing nanoparticles with magneto-optical activity arise as a consequence of radiative corrections to the electrostatic polarizability tensor.
Collapse
Affiliation(s)
- S Albaladejo
- Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | | | | | | | | | | | | | | | | |
Collapse
|
229
|
Wang JY, Tsai FJ, Huang JJ, Chen CY, Li N, Kiang YW, Yang CC. Enhancing InGaN-based solar cell efficiency through localized surface plasmon interaction by embedding Ag nanoparticles in the absorbing layer. OPTICS EXPRESS 2010; 18:2682-2694. [PMID: 20174098 DOI: 10.1364/oe.18.002682] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The use of localized surface plasmon (LSP) interaction for significantly enhancing InGaN absorption near its band edge and the overall efficiency of an InGaN-based solar cell by embedding Ag nanoparticles (NPs) in the InGaN absorbing layer is numerically demonstrated. The generation of LSP resonance on the embedded Ag NPs and the NP scattering can produce a field distribution in the InGaN layer for enhancing absorption. It is shown that the embedded Ag NPs do not significantly affect the transport of the photo-generated carriers. The distortion of static electrical stream lines in the solar cell due to the embedded Ag NP leads to a decrease of photocurrent by only a few percents. Based on the material parameter values we use, unless the surface recombination velocity at the interface between the Ag NP and surrounding InGaN is extremely high, Ag NP embedment in the absorbing layer of an InGaN-based solar cell can enhance its efficiency by up to 27%. Such an increase is significantly larger than that achieved by depositing metal NP on the top surface of a solar cell.
Collapse
Affiliation(s)
- Jyh-Yang Wang
- Department of Electrical Engineering, National Taiwan University, Institute of Photonics and Optoelectronics, No 1, Roosevelt Road, Section 4, Taipei 10617, Taiwan
| | | | | | | | | | | | | |
Collapse
|
230
|
Mäder M, Höche T, Gerlach JW, Perlt S, Dorfmüller J, Saliba M, Vogelgesang R, Kern K, Rauschenbach B. Plasmonic activity of large-area gold nanodot arrays on arbitrary substrates. NANO LETTERS 2010; 10:47-51. [PMID: 20014821 DOI: 10.1021/nl903633z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Highly efficient fabrication of well-ordered, embedded gold nanodot matrices using diffraction mask projection laser ablation is demonstrated. These gold nanodot arrays are ideally generated onto sapphire substrates but do also form onto AlO(x) thin films, enabling the application to arbitrary bulk substrates. Well-ordered gold dots become embedded into the Al(2)O(3) substrate during the process, thus improving their mechanical stability, chemical inertness, and technological compliance. Such substrates may be useful, for example, to enhance solar-cell efficiency by surface plasmons or as convenient, biocompatible focusing elements in nearfield optical tweezers.
Collapse
Affiliation(s)
- Marisa Mäder
- Leibniz Institute of Surface Modification, Permoserstrasse 15, Leipzig, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
231
|
Lee S, Shin J, Lee YH, Fan S, Park JK. Directional photofluidization lithography for nanoarchitectures with controlled shapes and sizes. NANO LETTERS 2010; 10:296-304. [PMID: 20017565 DOI: 10.1021/nl903570c] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Highly ordered metallic nanostructures have attracted an increasing interest in nanoscale electronics, photonics, and spectroscopic imaging. However, methods typically used for fabricating metallic nanostructures, such as direct writing and template-based nanolithography, have low throughput and are, moreover, limited to specific fabricated shapes such as holes, lines, and prisms, respectively. Herein, we demonstrate directional photofluidization lithography (DPL) as a new method to address the aforementioned problems of current nanolithography. The key idea of DPL is the use of photoreconfigurable polymer arrays to be molded in metallic nanostructures instead of conventional colloids or cross-linked polymer arrays. The photoreconfiguration of polymers by directional photofluidization allows unprecedented control over the sizes and shapes of metallic nanostructures. Besides the capability for precise control of structural features, DPL ensures scalable, parallel, and cost-effective processing, highly compatible with high-throughput fabrication. Therefore, DPL can expand not only the potential for specific metallic nanostructure applications but also large-scale innovative nanolithography.
Collapse
Affiliation(s)
- Seungwoo Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, 335 Gwahangno, Yuseong-gu, Daejeon, Republic of Korea
| | | | | | | | | |
Collapse
|
232
|
Bai W, Gan Q, Bartoli F, Zhang J, Cai L, Huang Y, Song G. Design of plasmonic back structures for efficiency enhancement of thin-film amorphous Si solar cells. OPTICS LETTERS 2009; 34:3725-3727. [PMID: 19953175 DOI: 10.1364/ol.34.003725] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Metallic back structures with one-dimensional periodic nanoridges attached to a thin-film amorphous Si (a-Si) solar cell are numerically studied. At the interfaces between a-Si and metal materials, the excitation of surface-plasmon polaritons leads to obvious absorption enhancements in a wide near-IR range for different ridge shapes and periods. The highest enhancement factor of the cell external quantum efficiency is estimated to be 3.32. The optimized structure can achieve an increase of 17.12% in the cell efficiency.
Collapse
Affiliation(s)
- Wenli Bai
- Nano-optoelectronics Laboratory, Institute of Semiconductors, Chinese Academy of Sciences,P.O. Box 912 Beijing 100083, China
| | | | | | | | | | | | | |
Collapse
|
233
|
Saeta PN, Ferry VE, Pacifici D, Munday JN, Atwater HA. How much can guided modes enhance absorption in thin solar cells? OPTICS EXPRESS 2009; 17:20975-90. [PMID: 19997336 DOI: 10.1364/oe.17.020975] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Absorption enhancement in thin metal-backed solar cells caused by dipole scatterers embedded in the absorbing layer is studied using a semi-analytical approach. The method accounts for changes in the radiation rate produced by layers above and below the dipole, and treats incoherently the subsequent scattering of light in guided modes from other dipoles. We find large absorption enhancements for strongly coupled dipoles, exceeding the ergodic limit in some configurations involving lossless dipoles. An antireflection-coated 100-nm layer of a- Si:H on Ag absorbs up to 87% of incident above-gap light. Thin layers of both strong and weak absorbers show similar strongly enhanced absorption.
Collapse
Affiliation(s)
- Peter N Saeta
- Department of Physics, Harvey Mudd College, Claremont, CA 91711, USA.
| | | | | | | | | |
Collapse
|
234
|
Ghadarghadr S, Hao Z, Mosallaei H. Plasmonic array nanoantennas on layered substrates: modeling and radiation characteristics. OPTICS EXPRESS 2009; 17:18556-70. [PMID: 20372586 DOI: 10.1364/oe.17.018556] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
In this paper, we theoretically characterize the performance of array of plasmonic core-shell nano-radiators located over layered substrates. Engineered substrates are investigated to manipulate the radiation performance of nanoantennas. A rigorous analytical approach for the problem in hand is developed by applying Green's function analysis of dipoles located above layered materials. It is illustrated that around the electric scattering resonances of the subwavelength spherical particles, each particle can be viewed as an induced electric dipole which is related to the total electric field upon that particle by a polarizability factor. Utilizing this, we can effectively study the physical performance of such structures. The accuracy of our theoretical model is validated through using a full-wave finite difference time domain (FDTD) numerical technique. It is established that by novel arraying of nano-particl and tailoring their multilayer substrates, one can successfully engineer the radiation patterns and beam angles. Several optical nanoantennas designed on layered substrates are explored. Using the FDTD the effect of finite size substrate is also explored.
Collapse
Affiliation(s)
- Shabnam Ghadarghadr
- Electromagnetics and Optical Devices Laboratory, ECE Department, Northeastern University,Boston, MA, 02115, USA
| | | | | |
Collapse
|
235
|
A Review of Ultrahigh Efficiency III-V Semiconductor Compound Solar Cells: Multijunction Tandem, Lower Dimensional, Photonic Up/Down Conversion and Plasmonic Nanometallic Structures. ENERGIES 2009. [DOI: 10.3390/en20300504] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
236
|
Hägglund C, Kasemo B. Nanoparticle plasmonics for 2D-photovoltaics: mechanisms, optimization, and limits. OPTICS EXPRESS 2009; 17:11944-11957. [PMID: 19582109 DOI: 10.1364/oe.17.011944] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Plasmonic nanostructures placed within or near photovoltaic (PV) layers are of high current interest for improving thin film solar cells. We demonstrate, by electrodynamics calculations, the feasibility of a new class of essentially two dimensional (2D) solar cells based on the very large optical cross sections of plasmonic nanoparticles. Conditions for inducing absorption in extremely thin PV layers via plasmon near-fields, are optimized in 2D-arrays of (i) core-shell particles, and (ii) plasmonic particles on planar layers. At the plasmon resonance, a pronounced optimum is found for the extinction coefficient of the PV material. We also characterize the influence of the dielectric environment, PV layer thickness and nanoparticle shape, size and spatial distribution. The response of the system is close to that of a 2D effective medium layer, and subject to a 50% absorption limit when the dielectric environment around the 2D layer is symmetric. In this case, a plasmon induced absorption of about 40% is demonstrated in PV layers as thin as 10 nm, using silver nanoparticle arrays of only 1 nm effective thickness. In an asymmetric environment, the useful absorption may be increased significantly for the same layer thicknesses. These new types of essentially 2D solar cells are concluded to have a large potential for reducing solar electricity costs.
Collapse
Affiliation(s)
- Carl Hägglund
- Department of Applied Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden.
| | | |
Collapse
|