Poster session IV
A single-crystalline silver nanoparticle on SiO2 substrate directly fabricated by focused ion beam milling
Tomohiro Mori (1), Yasuhiro Tanaka (1), Yoshifumi Suzaki (1), Toshihiro Okamoto (2), Kenzo Yamaguchi (1)
(1)Kagawa University (Japan), (2)The University of Tokushima (Japan) A single-crystalline silver nanoparticle was directly fabricated into the (111)-oriented large grain by focused ion beam milling. Electron backscatter diffraction (EBSD) methods elucidate the grain-growth mechanism in deposited silver films and the crystal orientation of the silver nanoparticle. Furthermore, the light intensity of scattering spectrum was obtained for the single-crystalline silver nanoparticle, and observed surface plasmon resonance. These results provide information for direct fabrication of the single-crystalline silver nanoparticle using physical processing methods.
Templated plasmonic nanostructures for use in non-linear chiroptical spectroscopy
Calum Jack, R. Leyman, A. S. Karimullah, R. Tullius, N. Gadegaard, M. Kadodwala
University of Glasgow (United Kingdom) Many important biological and pharmaceutical molecules are chiral and their chirality is fundamentally linked to their biological function. Sensitivity to this biomolecular chirality is essential in applications such as biomedical diagnostics and pathogen detection. In this talk we demonstrate the potential of high -throughput chiral plasmonic metamaterials as tool for the ultrasensitive detection of a range of biomolecules.
Structurally dark nano-materials: from perfect broadband absorption to monochromatic emission through light condensation
Changxu Liu, J. Huang, S. Masala, E. Alarousu, Y. Han, Andrea Fratalocchi
King Abdullah University of Science and Technology (Saudi Arabia) We designed a nanostructured absorber that shows an exceptional darkness, with an extremely high absorption > 98 percent between 400 nm and 1200 nm. By introducing an optical amplifier to the system, we show how to create a new type of source with the aid of the structural darkness, generating monochromatic emission without the need of any resonance. This behavior is achieved through a process of light condensation, which spontaneously transfer all the available spectral energy into a single frequency.
Modulated Light Transmission through a Subwavelength Slit at Early Stage
Jian-Shiung Hong (1), Alexander Ewen Chen (2), Kuan-Ren Chen (1)
(1)National Cheng Kung University (Taiwan), (2)The Pennsylvania State University (USA) The early dynamics of light transmission through a subwavelength slit in a finite-difference time-domain simulation shows that the amplitude of the transmitted light can be modulated. This underneath physics is studied with a new model. Besides academic importance, this phenomena and its understanding is essential to photonic applications utilizing short temporal pulses in a width of several to tens of light periods.
Application of the Mathieu's equation for an analysis of photonic crystal - supported surface electromagnetic waves
Ekaterina Rostova, Sergey Sekatskii, Giovanni Dietler
Ecole Polytechnique Federale de Lausanne (Switzerland) Nowadays, unique characteristics of surface electromagnetic waves, particularly, surface plasmons, supported by specially designed photonic crystals find numerous applications. We propose to exploit an evident analogy between such a photonic crystal and a structure with a sine-modulated refraction index. The propagation of light inside the latter is described by the famous Mathieu's differential equation. This application of the Mathieu's equation can be useful for a design of multilayered structures, also for fundamental understanding of electromagnetic phenomena in inhomogeneous media.
Fabrication of plasmonic nanoantennas by femtosecond direct laser writing lithography for surface-enhanced infrared absorption
Shahin Bagheri, Ksenia Weber, Timo Gissibl, Thomas Weiss, Frank Neubrech, Harald Giessen
University of Stuttgart (Germany) We demonstrate the use of femtosecond direct laser writing combined with argon ion beam etching to prepare homogenous and large-area nanoantenna arrays with feature sizes below the diffraction limit of the laser light. Such nanoantennas provide tunable and high quality plasmon resonances in the mid-infrared spectral range which are well-suited for surface-enhanced infrared absorption (SEIRA). We demonstrate that and experimentally investigate the influence of plasmonic coupling between neighboring nanoantennas on the SEIRA enhancement effect.
Tuning the Resonance Frequency and Polarization of Plasmonic Nanorods through Geometry, Material, and Substrate Changes
Andrew Lawson (1), Chase Ellis (2), Joseph Tischler (2), Oded Rabin (1)
(1)University of Maryland (USA), (2)U.S. Naval Research Laboratory (USA) The tunability of the frequency and polarization of surface plasmon resonances of nanostructures is crucial for their implementation in nanophotonics applications. We report FTIR spectroscopic data of gold and aluminum plasmonic nanorods with resonance frequencies spanning the mid-infrared regime (2-10 microns). The effect of the nanorod material and dimensions as well as substrate material is investigated. Bending of the nanorods results in additional resonances with polarizations not observed in straight nanorods.
An algorithmic approach to plasmonic filter design with applications to 3D directional light sensors
Matthew Davis (1), Jay Lee (1), Amit Agrawal (2), Henri Lezec (2)
(1)Syracuse University (USA), (2)Center for Nanoscale Science and Technology (USA) In this work we have developed an efficient analytical method for the design of plasmonic filters. We demonstrate the usefulness of this model by designing a plasmonic 3D directional light sensor based on the bulls-eye structure.
Surface Plasmon excitation via a finite number of sub-l defects at a metallic interface
Raul Garcia-Llamas (1), Sandra Gastelum-Acuna (2), Aldo Ramirez-Duverger (1)
(1)Universidad de Sonora (Mexico), (2)Universidad de Sonora CONACYT (Mexico) An experimental and theoretical study of the surface plasmon excitation via a finite number of sub-l defects at a metallic interface when it is illuminated for a Gaussian transverse magnetic polarized beam, is presented. The defects are grooves, for the case of gratings, or wells for the case of bi-gratings. The samples are fabricated by exposing photo-sensible films in the region of interferences of two beams. The maximum coupling strength is measured with the minimum of the specular reflection.
Extreme confinement of low-loss hybrid plasmonic modes in deep nano-scale layered structure
Reyad Mehfuz, Paul Dawson
Queen's University Belfast (United Kingdom) We propose a tri-layer planar structure to realize photonic waveguiding in deep nano-scale. The structure consists of silver, and silicon, which are separated by an ultra-thin layer of magnesium-oxide (MgO). With proper selection of materials and corresponding geometries, we show that sub-10 nm thick MgO layer can sustain a low-loss hybrid plasmonic mode. It enhances the energy density in the layer and provides extreme confinement with a mode area, which is 100 times smaller than a diffraction-limited waveguide.
Enhanced light emission of ZnO/Ag nanogratings: surface plasmon polariton and resonance mode excitation
Minji Gwon, Dong-Wook Kim
Ewha Womans University (Korea) We observed significant enhancement of the photoluminescence (PL) intensity from ZnO/Ag nanogratings. Polarization dependence of the PL and angle-resolved reflectance spectra showed that the cavity resonance in the gratings as well as grating-coupled surface plasmon polariton (SPP) excitation played crucial roles in the optical characteristics. The SPP and resonance mode excitation caused strong optical field confinement in the ZnO layers, resulting in distinct surface photovoltage behaviors depending on the incident light polarization.
Excitation of plasmonic nanoantennas with electron tunneling. Comparison of resonant and nonresonant tunneling
Alexander Uskov (1), Jacob Khurgin (2), I. Protsenko (1)
(1)Russian Academy of Sciences (Russia), (2)Johns Hopkins University (USA) Incorporating a resonant tunneling structure inside the gap of plasmonic nanoantennas can lead to manifold increase of the efficiency of electrical excitation of the surface plasmon polaritons, and may enable future electrically-driven nanoplasmonic circuits.
Tunable cavity-coupled plasmonic perfect absorber for ultra-compact thermo-optical switching
Mohsen Bahramipanah, Shourya Dutta-Gupta, Toralf Scharf, Olivier Martin
Swiss Federal Institute of Technology (Switzerland) A tunable cavity-coupled plasmonic perfect absorber based on liquid crystal is demonstrated.The optical response of the structure can be controlled by applying an external heat source. The physical principles of this phenomenon rely on the interplay between the phase of localized surface plasmon resonances in the nanostructures, the Fabry-Perot modes of the cavity and the thermooptical effect of the liquid crystals. Our experimental results demonstrate a large tuning range of 39 nm in the absorption spectrum of the structure.
Interaction of LSP resonances and Fabry-Perot cavity modes
Mohsen Bahramipanah, Shourya Dutta-Gupta, Banafsheh Abasahl, Olivier Martin
Swiss Federal Institute of Technology (Switzerland) We experimentally and numerically demonstrate the coupling between Fabry-Perot modes of the microcavities and the localized surface plasmon resonance of metallic nanostructures. Coupling the plasmonic nanostructures to a Fabry-Perot microcavity creates compound modes, which have the characteristics of both Fabry-Perot and the LSPR modes. The special features of the proposed structure and the device concept introduced in this work are applicable in the realization of ultra-high sensitive plasmonic devices for biosensing, optoelectronics, and related technologies.
Self-assembly lithography of Quantum dot nanogap metamaterials
Laxmi N. Tripathi, Taehee Kang Kang, Young-Mi Bahk, Sanghoon Han, Geunchang Choi, Jiyeah Rhie, Jeeyoon Jeong, Dai-Sik Kim
Seoul national university (Korea) We present a novel self-assembly lithography method to fabricate a large scale cadmium selenide quantum dots-silver nanogap metamaterial. We measured spatially resolved photoluminescence through the nanogap showing the presence of quantum dots inside the gap. This metamaterial will find versatile applications in optical and terahertz technology, for examples, cavity quantum electrodynamics, molecular sensing, Nanogap quantum dot photo detectors etc.
Electrical Tuning of Plasmonic Properties of Transparent Conductive Oxides with a Liquid Electrolyte
Ju-Hyung Kang, Hongtao Yuan, Xiaoge Liu, Junghyun Park, Mark Brongersma
Stanford University (USA) We demonstrate electrical tuning of the plasma frequency of indium tin oxides by changing the sheet carrier density by electrical gating with an ionic liquid. The significant changes in the optical and electronic properties are quantified using optical reflection, sheet conductivity, and Hall measurements. The transfer matrix method simulation studies successfully reproduce the experimental results. Our observation can therefore offer the capability to develop efficient electro-optic devices.
Optical properties of one-dimensional photonic crystal containing a defect
Jong Bin Yeo, Cheol Jin Park, Heon Kong, Hyun Yong Lee
Chonnam National University (Korea) Ten-pair TeO2/SiO2 one-dimensional photonic crystal (1D PC) has been investigated. The 1D PC containing a single defect layer of Ta2O5 generated a selective transmittance in photonic band gap (PBG). The 1D PC structure was designed by transfer matrix method (TMM), and fabricated by rf sputtering technique. The samples are exposed by He-Cd laser and He-Ne laser to evaluate the variation of optical properties before and after illuminating light. The fabricated 1D PC structure was measured by UV-VIS-NIR spectrophotometer.
Topologically Protected States in Continuous Systems and Applications to Photonics
Charles L. Fefferman (1), James P. Lee-Thorp (2), Michael I. Weinstein (2)
(1)Princeton University (USA), (2)Columbia University (USA) We outline a rigorous bifurcation theory of topologically protected edge states in 1D dimer structures and 2D honeycomb structures. Our models are continuous Schroedinger operators with potentials consisting of two parts: a bulk periodic potential having Dirac points and a domain wall interpolation between asymptotic periodic structures. We also present a photonic realization of the edge states of dimer structures as highly robust guided wave modes for a class of dielectric structures.
The anomalies of the optical transmission of potash alumoboron glasses with fe2O3 additives induced by gamma radiation
E. M. Ibragimova (1), O. K. Kuvandikov (2), M. K. Salakhitdinova (2)
(1)Institute of Nuclear Physics Academy of Science (Uzbekistan), (2)Samarkand State University (Uzbekistan) As the basic object of investigation have been used the glass which contains Fe2O3 in the form of additives from 0,1 to 3.0 mass.percent over 100percent. The obtained experimental data are explained well enough on the basis of the development of the phenomenological theory of the radiative-induced processes at the thermal and thermoradiating treatments.
Surface Wave Suppression Using Graphene at Microwave Frequencies: Application to Microwave Cancer Treatment
Hulusi Acikgoz (1), Raj Mittra (2)
(1)KTO Karatay University (Turkey), (2)The Pennsylvania State University (USA) This paper deals with the application of a single layer of graphene as a high impedance surface for reducing backward heating problem caused by surface current generated along the outer conductor of a microwave coaxial slot antenna. By having a graphene layer wrapped on the outer conductor of the coaxial antenna we show that one can suppress the surface current along the antenna.
Hyperbolic-gap-hyperbolic tunable band structure metamaterials
Georgia T. Papadakis, Krishnan Thyagarajan, Harry A. Atwater
CALTECH (USA) We introduce a motif for active tuning of the effective optical parameters of planar hyperbolic metamaterials. Using the field effect, we gate and electrically modulate the permittivity in transparent conductive oxide (TCO) layers via changes in the carrier density. This enables broadband active modulation of the anisotropy characteristics of metamaterials. We observe opening and closing of omnidirectional band gaps within the visible regime. A sensitivity analysis over the electronic characteristics of TCOs assures experimentally measurable modulation over those parameters.
Ultrasensitive detection of ligand-induced conformational changes in proteins using chiral plasmonic nanostructures.
Ryan Tullius (1), A. S. Karimullah (1), Calum Jack (1), M. Rodier (1), B. Fitzpatrick (1), A. Lapthorn (1), G. Cooke (1), N. Gadegaard (1), V. M. Rotello (2), M. Kadodwala (1)
(1)University of Glasgow (United Kingdom), (2)University of Massachusetts (USA) The ability to screen libraries of chemical compounds, or fragments, against a protein target is the basic starting point in the search for a novel therapeutic agent in drug discovery. Here we introduce a new chip based biophysical measurement technology that would be a powerful tool for high throughput screening. We show that gold, plasmonic, substrates imprinted with chiral nanostructures can be used to rapidly detect ligand-induced changes of the protein tertiary and quaternary structure.
Full quantum statistics of plasmon - multi quantum emitter coupling and spasers
Michael Gegg, T. S. Theuerholz, A. Knorr, M. Richter
Technische Universitat Berlin (Germany) Nanoplasmonic emitters, such as spasers, are needed to supply coherent plasmons and overcome the problem of short lifetimes. In terms of laser theory the spaser is a laser in the bad cavity limit, with extremely high Purcell factors and mesoscopic system sizes - a regime where standard approaches fail. We present a numerically exact, non-perturbative investigation of the full statistical properties of coupled metal nanoparticle/many quantum emitter systems in the spaser limit.
Coupling hyper-sound generated by molecular transducers to plasmonic nanorods
Elena Pavlenko, Steffen Mitzscherling, Wouter Koopman, Matias Bargheer
University of Potsdam (Germany) We designed and prepared nanolayered composites containing gold nanorods as plasmonic sensors and azobenzene-polyelectrolytes as opto-acoustic transducers. The multilayered structure of Azobenzene-containing polymer is prepared by the layer-by-layer spin coating procedure. A sound wave is triggered by excitation of Azobenzene molecules and then detected by gold nanorods, due to the sensitivity of their plasmon resonance to the surrounding media.
Polarization Controllable THz Stereometamaterial Absorber
Mohammad P. Hokmabadi, Juhyung Kim, Soner Balci, Elmer Rivera, Patrick Kung, Seongsin M. Kim
The University of Alabama (USA) Spatially different arrangements of identical meta-atoms in a unit cell bring about distinct properties in stereometamaterials. Integrating the stereometamaterial into a perfect metamaterial absorber, we designed, fabricated, characterized a device with single or double band absorption responses and an absorption/reflection switching characteristic dependent upon the polarization of incident THz wave. Despite the rotational symmetry of the rings, non-centricity breaks the reflection symmetry of the FSS, leading to a unique interaction between dipoles on the FSS and their mirror images.
Graphene-Enhanced Near-Field Radiative Transport between a Nanostructured Metamaterial Emitter and a Planar Receiver
Jui-Yung Chang, Yue Yang, Liping Wang
Arizona State University (USA) It becomes crucial for applications like near-field thermophotovoltaic to achieve strong near-field energy transfer between dissimilar materials, while coupled surface plasmon/phonon polaritons and hyperbolic modes usually require identical materials across nanometer vacuum gaps. In this work, we theoretically study near-field radiative transport between a nanostructured metamaterial emitter and a planar receiver covered by graphene. Strong near-field coupling up to two orders of magnitude enhancement can be achieved. The physical mechanisms are elucidated with fluctuational electrodynamics and dispersion relations.
Theoretical Diffraction and Imaging Assessment of Multi-Layer Metamaterial Microwave Lens Operated Under Fast F/1 Geometries
Steve Kacenjar (1), Tamelia Ali (2), Igor Bendoym (3), Andrii Golovin (2), David Crouse (2)
(1)Lockheed Martin corporation (USA), (2)City University of New York (USA), (3)Phoebus Optoelectronics (USA) With the advent of lightweight, low cost and spatially stationary metamaterial-based microwave scanning/imaging systems, key questions remain as to their imaging quality effectiveness. Methods such as varactor-controlled metamaterials and metasurfaces provide distinctive approaches in shaping the microwave radiation, yet their robustness to operational bandwidth, loss tangents, and off-axis deployment may limit their utility in various operational setting such as in remote sensing, radar and communication systems. This paper compares the analytic scaling to numerical estimation of such system focusing properties.
Bio-Inspired Hierarchical Acoustic Metamaterials
Marco Miniaci (1), Federico Bosia (2), Nicola Pugno (3)
(1)Department of Physics - University of Torino (Italy), (2)University of Torino (Italy), (3)University of Trento (Italy) Many biological systems show extremely efficient structural as well as dynamic properties achieved through their structure, which is often hierarchical. In this study, such a hierarchical structure is introduced in ordinary acoustic metamaterials (AMMs) to investigate partial and complete BGs modifications due to increasing structural complexity at different scale levels.
Near-field Energy Extraction with Hyperbolic Metamaterials
Jiawei Shi, Baoan Liu, Pengfei Li, Li Yen Ng, Sheng Shen
Carnegie Mellon University (USA) Although blackbody radiation described by Planck's law is commonly regarded as the maximum of thermal radiation, thermal energy transfer in the near-field can exceed the blackbody limit due to the contribution from evanescent waves. Here, we demonstrate experimentally a broadband thermal energy extraction device based on hyperbolic metamaterials that can significantly enhance near-field thermal energy transfer.
Exciton-Polariton Laser with Saturable Absorber
I. G. Savenko (1), H. Flayac (2), N. N. Rosanov (3)
(1)Aalto University (Finland), (2)Ecole Polytechnique Federale de Lausanne (Switzerland), (3)ITMO University (Russia) We consider exciton polaritons in a semiconductor microcavity with a saturable absorber. Such design promotes nonlinear losses of the system with a bistability of the condensate particles number on the intensity of pump. We demonstrate new type of bright spatial dissipative exciton-polariton soliton which spatial extent lies in the sub-micrometer range, much smaller than the typical widths of regular optical dissipative solitons.
Application of the transition semiconductorto semimetal in type II nanostructure superlattice for mid infrared optoelectronics devices.
Abderrazak Boutramine, Abdelhakim Nafidi, Driss Barkissy, Abdelkrim Hannour, Ahmed Saba, Thami El Gouti
LCMP Nano Re-University Ibn Zohr (Morocco) We report here electronic bands structures in InAs (d1)/GaSb (d2) type II superlattice performed in the envelope function formalism. When d1 (or the offset) increases, the band gap Eg decreases to zero at d1c (or 920 meV) accusing a semiconductor to semimetal transition. The cut-off wavelength situates this sample, with Eg (300K) = 230 meV, as mid-wavelength infrared detector (MWIR). These results agree well with the experimental Eg (T) data reported in literature.
Real space observation of percolation clusters and their evolution in nearly grain-boundary-free VO2/TiO2 thin films
Ahrum Sohn (1), Dong-Wook Kim (1), Teruo Kanki (2), Kotrao Sakai (2), Hidekazu Tanaka (2)
(1)Ewha Womans University (Korea), (2)Osaka University (Japan) We investigated the surface work function (WS) of 15-nm-thick nearly grain-boundary-free VO2/TiO2 thin films using Kelvin probe force microscopy (KPFM). WS maps obtained while varying the sample temperature enabled us to observe metallic and insulating domains with distinct WS values, while the sample underwent the metal-insulator transition.
Plasmonic Focus Points for Sensing Chiral Molecules
Luisa Magdalena Kneer (1), Eva-Maria Roller (1), Robert Schreiber (2), Tim Liedl (1)
(1)Ludwig Maximilans Universitat (Germany), (2)University of Oxford (United Kingdom) Naturally occurring biomolecules often exhibit strong optical activity in the UV, but usually none in the visible frequency range. Plasmonic nanostructures can transfer the optical activity of the biological molecules to their plasmon resonance frequency. Here we demonstrate a unique approach to pick up the circular dichroism (CD) signal of regular B-DNA in the visible and near infrared by using gold nanoantennas self-assembled on DNA origami structures.
Photo-striction and reversible patterning of polymer-on-metal nanostructures with a plasmonic hologram
Carsten Henkel, J. Jelken, B. Stiller, D. Neher, T. Papke, Nataraja Sekhar Yadavalli, S. Santer
University of Potsdam (Germany) Surface plasmons in thin metallic films can be excited by nm-scale defects (grooves, pits) and interfere with the incident laser field. We observe this plasmonic hologram with a polymer film containing azo-benzene chromophores that is coated on the metal. It deforms into a surface relief when exposed to plasmons. The azo-benzene units isomerize and re-orient depending on local intensity and polarization. The relief period (plasmon fringes) gives access to the dispersion relation of surface plasmons in the multilayer metal-on-substrate structure.
ZnO/Au-based Surface Plasmon Resonance Device for CO2 Gas Detection
Ratno Nuryadi, R. D. Mayasari, L. Aprilia
Agency for the Assessment and Application of Technology (Indonesia) We propose surface plasmon resonance (SPR) device using ZnO/Au/prism and study its response to CO2 gas. The SPR device is based on Kretschmann's prism configuration with ZnO/Au layer deposited on the flat surface of the prism. It is found that the absorption of gas molecules on the ZnO sensitive layer produces the shift of SPR angle to higher incident angle. A consistent sensing behavior over repetitive circles indicates that the SPR device works on good reproducibility for gas detection.
Chiroptical Sensing with Plasmonic Metasurfaces
Amr Shaltout, J. Liu, V. M. Shalaev, A. V. Kildishev
Purdue University (USA) Circular dichroism spectrometers measure the differential absorption spectrum between optical spins (circular polarizations) through taking sequential readings of left and right-handed spins at different wavelengths. This requires complicated hardware to switch the laser source and manage sequential data collections. Instead, we implement a metasurface which utilizes photonic spin Hall effect for spatial separation of left and right-handed spectra. This enables real-time sensing, and eliminates the need for the complicated hardware.
Direct Measurement of Far Field Radiation Patterns of Large Scale Aluminum Nanoantenna Arrays using Fourier Microscopy
Neciah Dorh (1), N. Ahmad (1), S. Nunez-Sanchez (1), M. Lopez-Garcia (1), G. Ternent (2), M. J. Cryan (1)
(1)University of Bristol (United Kingdom), (2)University of Glasgow (United Kingdom) In this paper, we present direct measurement of the far field radiation pattern produced by a 62,500 element aluminum nanoantenna array. The 250 x 250 array consists of nanorod/monopole nanoantennas separated by a uniform 409 nm pitch. Using the Fourier Microscopy technique, angle resolved reflectance measurements revealed a 40 percent peak reflectance at the nanoantenna array resonance (710 nm). Using Finite Difference Time Domain (FDTD) modelling of the array, we observe a similar peak of 68 percent near 690 nm.
Dyakonov surface waves in nanoparticle dispersed liquid crystal metamaterials
Mie University (Japan) We have investigated existence condition of lossless Dyakonov surface waves (DSWs) on nanoparticle dispersed liquid crystal (NDLC) metamaterials composed of nematic liquid crystal host dispersed with Ag nanoparticle inclusions. Effective dielectric permittivities of NDLCs are obtained by an extended Maxwell-Garnett mixing rule. We have shown that the existence condition for DSWs can be significantly relaxed allowing even air cladding. Our approach may open a new avenue exploring practical application of lossless DSWs with switching capabilities.
Leaky Dyakonov Surface Plasmon Polaritons for Birefringent Crystals
Ardi Loot, Vladimir Hizhnyakov
University of Tartu (Estonia) The surface waves propagating at the interface of metal and positive birefringent crystal, usually called Dyakonov surface plasmon polaritons (DSPPs), were theoretically investigated. It was shown, that at special conditions the extraordinarily polarized component of DSPPs could become leaky. The properties of such half-leaky waves were theoretically investigated and it was shown that these surface waves could be excited without any prism or grating. This is especially beneficial in the experiments of nonlinear optics where field enhancement is required.