Prof. Wojciech Nasalski, Ph.D., Dr. Habil. 

Doctoral thesis
1975  Kwantowanie pól sprężystych
 268 
Habilitation thesis
1991  Niespekularne odbicie pola elektromagnetycznego na granicy dwu dielektryków 
Professor
20090617  Title of professor 
Supervision of doctoral theses
1.  20120628  Roszkiewicz Agata  Generacja plazmonów polarytonów powierzchniowych na strukturach periodycznych  650  
2.  1995  Burak Dariusz  Propagacja solitonów przestrzennych generowanych wiązkami Gaussa w nieliniowym ośrodku Kerra 
Recent publications
1.  Roszkiewicz A., Jain A., Teodorczyk M.^{♦}, Nasalski W., Formation and Characterization of Hole Nanopattern on Photoresist Layer by Scanning NearField Optical Microscope
, Nanomaterials, ISSN: 20794991, DOI: 10.3390/nano9101452, Vol.9, No.1452, pp.111, 2019 Abstract: PatterningoflinesofholesonalayerofpositivephotoresistSXARP3500/6(AllresistGmbH, Strausberg, Germany) spincoated on a quartz substrate is carried out by using scanning nearﬁeld optical lithography. A green 532 nmwavelength laser, focused on a backside of a nanoprobe of 90 nm diameter, is used as a light source. As a result, after optimization of parameters like laser power, exposuretime,orsleeptime,itisconﬁrmedthatitispossibletoobtainauniformnanopattern structure in the photoresist layer. In addition, the lines of holes are characterized by a uniform depth (71–87nm)andrelativelyhighaspectratiorangingfrom0.22to0.26. Numericalmodellingperformed with a rigorous method shows that such a structure can be potentially used as a phase zone plate. Keywords:optical lithography; photoresist; quartz; hole nanopatterning Affiliations:
 
2.  Nasalski W., Elegant Laguerre–Gaussian beams — formulation of exact vector solution, Journal of Optics, ISSN: 20408978, DOI: 10.1088/20408986/aadc8a, Vol.20, No.105601, pp.111, 2018 Abstract: In photonic applications of optical beams, their transverse crosssection should be often narrow, with a diameter in their waist of the order of one wavelength or even less. Within this range, the paraxial approximation of beam fields is not valid and standard corrections by field expansions with respect to a small parameter are not efficient as well. Thus, still there is a need for more accurate beam field description. In this report, an exact vector solution for freespace propagation is given in terms of elegant Laguerre–Gaussian beams. The analysis starts from the known paraxial field approximation and next, through bidirectional field transformation and application of a Hertz potential leads to an exact vector solution. The role of the paraxial solution in construction of the exact solution is elucidated. The method works well not only in cases of freespace propagation but also in description of beam interactions with planar interfaces and multilayers. Keywords:elegant Laguerre–Gaussian beams, paraxial and nonparaxial solutions, bidirectional transformation, Hertz potentials Affiliations:
 
3.  Roszkiewicz A., Nasalski W., Transmission and reflection properties of twodimensional finite metal crystals, EUROPEAN PHYSICAL JOURNAL D, ISSN: 14346060, DOI: 10.1140/epjd/e2017707069, Vol.71, No.182, pp.112, 2017 Abstract: Optical characteristics of a finite twodimensional silver stripe photonic crystal of a square lattice are numerically analysed with use of multilayer Rigorous Coupled Wave Analysis. Qualitative changes in optical response of the crystal originated from modifications of the thickness and filling factors of each layer and the polarization direction of the incident wave are shown. The crystal manifests its various characteristics in wideband or narrowband reflection and transmission, while absorption remains low. The behaviour of the crystal is determined by its structure geometry yielding excitation of localized plasmons and collective modes together with interactions between them. The optical response of the square lattice structure is also compared with the response of a triangular lattice crystal. Affiliations:
 
4.  Roszkiewicz A., Nasalski W., Optical beam interactions with a periodic array of Fresnel zone plates, JOURNAL OF PHYSICS BATOMIC MOLECULAR AND OPTICAL PHYSICS, ISSN: 09534075, DOI: 10.1088/09534075/47/16/165401, Vol.47, pp.16540119, 2014 Abstract: The interactions of firstorder elegant Laguerre–Gaussian beams (ELG) with a twodimensional periodic array are analysed theoretically and numerically. The structure consists of a periodic composition of twozone Fresnel plates engraved in a silver film. The beam field is composed of periodic sequences of beams of circular or polar polarization incidence upon the structure. The beam axes coincide with the symmetry axes of every fourth Fresnel zone plate placed periodically along two orthogonal coordinates of a horizontal plane of the structure. It is shown that the beamstructure interaction results in substantial crosspolarization coupling, higherorder mode excitation, strong focussing and the extraordinary transmission of the optical field. An interpretation of the results is given per an analogy to the beamstructure interactions observed at planar, homogeneous and isotropic dielectric interfaces and layers. Affiliations:
 
5.  Nasalski W., Vortex and antivortex compositions of exact elegant Laguerre–Gaussian vector beams, APPLIED PHYSICS BLASERS AND OPTICS, ISSN: 09462171, DOI: 10.1007/s0034001458203, Vol.115, pp.155159, 2014 Abstract: Reformulation of conventional beam definitions into their bidirectional versions and use of Hertz potentials make beam fields exact vector solutions to Maxwell’s equations. This procedure is applied to higherorder elegant Laguerre–Gaussian beams of transverse magnetic and transverse electric polarization. Their vortex and antivortex coaxial compositions of equal and opposite topological charges are given in a closed analytic form. Polarization components of the composed beams are specified by their radial and azimuthal indices. The longitudinal components are common for beam compositions of both types; meanwhile, their transverse components are different and comprise two—nonparaxial and paraxial—separate parts distinguished by a paraxial parameter and its inverse, respectively. The new solutions may appear useful in modeling and tailoring of arbitrary vector beams. Affiliations:
 
6.  Nasalski W., Exact elegant LaguerreGaussian vector wave packets, OPTICS LETTERS, ISSN: 01469592, DOI: 10.1364/OL.38.000809, Vol.38, No.6, pp.809811, 2013 Abstract: An exact closedform representation is derived of a vector elegant Laguerre–Gaussian wave packet. Its space–time representation consists of three mutually orthogonal field components—of a common azimuthal index and different radial indices—uniquely distinguished by first three powers of the paraxial parameter. The transverse components are of tmradial and teazimuthal polarization and appear, under their normal incidence, to be eigenmodes of any horizontally planar, homogeneous and isotropic structure, with eigenvalues given by the reflection and transmission coefficients. In this context, the interrelations between the crosspolarization symmetries of wave packets in free space and at medium planar interfaces are discussed. Affiliations:
 
7.  Roszkiewicz A., Nasalski W., Resonant transmission enhancement at onedimensional metal gratings, JOURNAL OF PHYSICS BATOMIC MOLECULAR AND OPTICAL PHYSICS, ISSN: 09534075, DOI: 10.1088/09534075/46/2/025401, Vol.46, pp.16, 2013 Abstract: An analysis of phenomena leading to high transmission at a onedimensional metal grating is presented. It is shown that high resonant transmission can be obtained either for thick or thin gratings for a wide range of filling factors and that the origins of the enhanced transmission are different in each case. We analyse the optical response of structures with subwavelength slits and of various thicknesses. The role of different pure (dielectric cavity modes, surface plasmon polaritons) and coupled resonances on the enhanced transmission is presented. Affiliations:
 
8.  Roszkiewicz A., Nasalski W., Extraordinary optical transmission and vortex excitation by periodic arrays of Fresnel zone plates, BULLETIN OF THE POLISH ACADEMY OF SCIENCES: TECHNICAL SCIENCES, ISSN: 02397528, DOI: 10.2478/bpasts20130092, Vol.61, No.4, pp.855861, 2013 Abstract: Extraordinary optical transmission and good focusing properties of a twodimensional scattering structure is presented. The structure is made of Fresnel zone plates periodically arranged along two orthogonal directions. Each plate consists of two ringshaped waveguides supporting modes that match the symmetry of a circularly polarized incident plane wave. High field concentration at the focal plane is obtained with the short transverse and long longitudinal foci diameters. Optical vortex excitation in a paraxial region of the transmitted field is also observed and analysed in terms of crosspolarisation coupling. The structure presented may appear useful in visualization, trapping and precise manipulations of nanoparticles. Keywords:Fresnel zone plates, focusing, crosspolarisation coupling, optical vortices Affiliations:
 
9.  Roszkiewicz A., Nasalski W., Reflection suppression and absorption enhancement of optical field at thin metal gratings with narrow slits, OPTICS LETTERS, ISSN: 01469592, Vol.37, No.18, pp.37593761, 2012  
10.  Szabelak W., Nasalski W., Enhancement of crosspolarized beam components at a metamaterial surface, APPLIED PHYSICS BLASERS AND OPTICS, ISSN: 09462171, Vol.103, No.2, pp.369375, 2011  
11.  Szabelak W., Nasalski W., Crosspolarization coupling and switching in an open nanometaresonator, JOURNAL OF PHYSICS BATOMIC MOLECULAR AND OPTICAL PHYSICS, ISSN: 09534075, Vol.44, pp.215403110, 2011  
12.  Roszkiewicz A., Nasalski W., Unidirectional SPP excitation at asymmetrical twolayered metal gratings, JOURNAL OF PHYSICS BATOMIC MOLECULAR AND OPTICAL PHYSICS, ISSN: 09534075, Vol.43, pp.18540118, 2010  
13.  Nasalski W., Elegant HermiteGaussian and LaguerreGaussian beams at a dielectric interface, OPTICA APPLICATA, ISSN: 00785466, Vol.40, No.3, pp.615622, 2010  
14.  Nasalski W., Crosspolarized normal mode patterns at a dielectric interface, BULLETIN OF THE POLISH ACADEMY OF SCIENCES: TECHNICAL SCIENCES, ISSN: 02397528, Vol.58, No.1, pp.141154, 2010  
15.  Szabelak W., Nasalski W., Transmission of Elegant LaguerreGaussian beams at a dielectric interface  numerical simulations, BULLETIN OF THE POLISH ACADEMY OF SCIENCES: TECHNICAL SCIENCES, ISSN: 02397528, Vol.57, No.2, pp.181188, 2009  
16.  Roszkiewicz A., Szabelak W., Nasalski W., Surface plasmon polariton applications in selected branches of modern science and technology, JOURNAL OF TECHNICAL PHYSICS, ISSN: 03248313, Vol.50, pp.402530, 2009  
17.  Nasalski W., Pagani Y., Excitation and cancellation of higherorder beam modes at isotropic interfaces, JOURNAL OF OPTICS APURE AND APPLIED OPTICS, ISSN: 14644258, DOI: 10.1088/14644258/8/1/004, Vol.8, pp.2129, 2006 Abstract: The phenomenon of excitation and cancellation of higherorder elegant Hermite–Gaussian and Laguerre–Gaussian threedimensional beams, induced at a dielectric isotropic interface by crosspolarization coupling, is analysed. The crosspolarization effect depends quantitatively on interrelations between beam field spatial distribution and beam polarization. These relations are derived for two basic cases of linear and circular polarization and confirmed by numerical simulations. Affiliations:
 
18.  Nasalski W., Polarization versus spatial characteristics of optical beams at a planar isotropic interface, PHYSICAL REVIEW E, ISSN: 15393755, Vol.74, pp.56613116, 2006  
19.  Pagani Y., Nasalski W., Diagonal relations between elegant HermiteGaussian and LaguerreGaussian beam fields, OPTOELECTRONICS REVIEW, ISSN: 12303402, Vol.13, No.1, pp.5160, 2005  
20.  Nasalski W., Amplitudepolarization representation of threedimensional beams at a dielectric interface, JOURNAL OF OPTICS APURE AND APPLIED OPTICS, ISSN: 14644258, DOI: 10.1088/14641258/5/2/309, Vol.5, No.2, pp.128136, 2003 Abstract: Threedimensional optical beams incident on a dielectric interface undergo deformations upon reflection and refraction. Within firstorder optics these deformations may be interpreted as longitudinal and transverse displacements and deflections of beam axes. In general, these effects are different for TE and TM components of the beam field. The problem of beam reflection and refraction at the interface is formulated and solved in such a manner that the beams are obtained with uniquely defined uniform displacements of their axes in a spatial domain and their spectrum centres in a spectral domain. Additional modifications of the beam polarization state remain generally small and nonuniform throughout the entire beam spectrum. In this context, a special role of polarization states diagonal in the interface plane is indicated. Keywords:Beam optics, polarization optics, reflection, refraction, Lorentz group Affiliations:
 
21.  Nasalski W., Beam switching at planar photonic structures, OPTOELECTRONICS REVIEW, ISSN: 12303402, Vol.9, No.3, pp.280286, 2001 Abstract: Beam reflection at a focusing nonlinearlinear interface near critical incidence of total internal reflection is analysed. nonspecular reflection, nonlinear interfaces, beam switching, optical bistability Affiliations:
 
22.  Nasalski W., Threedimensional beam reflection at dielectric interfaces, Optics Communications, ISSN: 00304018, DOI: 10.1016/S00304018(01)014201, Vol.197, pp.217233, 2001 Abstract: Polarisation, amplitude and beam shape aspects of the threedimensional optical beam reflection at dielectric interfaces are analysed within a framework of the aberrationless approach. Roles of the paraxial approximation, the crossdimensional coupling and the nonparaxial crosspolarisation coupling in the beam description are discussed. It is shown that the substantial firstorder transverse beam modifications exist for both – linear and circular – beam polarisation states. Characteristic features of the single beam bistable switch at nonlinear interfaces are also discussed and numerical examples of the reflected beam field reshaping are presented. Total internal reflection, Effects of nonspecular reflection, Beam shaping, Nonlinear interfaces, Optical bistability Affiliations:
 
23.  Nasalski W., Modelling of beam reflection at a nonlinear–linear interface, JOURNAL OF OPTICS APURE AND APPLIED OPTICS, ISSN: 14644258, DOI: 10.1088/14644258/2/5/314, Vol.2, No.5, pp.433441, 2000 Abstract: An analytic model of beam reflection at a nonlinear–linear interface is presented. nonlinear interfaces, optical bistability, nonspecular reflection Affiliations:
 
24.  Nasalski W., Bistable nonspecular reflection at a nonlinear–linear local interface, OPTICS LETTERS, ISSN: 01469592, DOI: 10.1364/OL.23.000433, Vol.23, No.6, pp.433435, 1998 Abstract: Nonspecular reflection at a nonlinear–linear dielectric interface with local Kerr nonlinearity is analyzed. The Fresnel reflectivity and the variational solution are explicitly given in a closed form. Bistable switching of the interface is demonstrated by numerical simulations based on the monotonic iteration procedure. Affiliations:
 
25.  Nasalski W., Nonspecular bistability at a delocalized nonlinear interface, JOURNAL OF MODERN OPTICS, ISSN: 09500340, DOI: 10.1080/09500349708230742, Vol.44, pp.13551372, 1997 Abstract: Bounded beams reflected at the interface between two dielectric media can undergo lateral displacements, focal shifts, angular deviations, changes in the beam waist size and complex amplitude. These effects are examined for beams incident from a linear medium onto a nonlinear defocusing Kerrtype material, where the nonlinear medium changes are supposed to be homogeneously nonlocal. An exact solution to the reflection problem is numerically iterated by a sequence of solutions to the respective linear problems and a rigorous firstorder analysis of the nonspecular phenomena is also given. The beaminterface interaction is described in terms of the Wigner distribution function invariant with respect to the nonspecular ABCD transformation. The results show that, for some specified beam parameters, the beam reflection may exhibit bistable switching, which is accompanied by bistable changes in all the nonspecular effects. Keywords:Nonlinear interface, GaussianBeam, NonspecularPhenomena, Dielectric Interface, Reflection, MediaLight, Displacement, Propagation, Shift Affiliations:
 
26.  Nasalski W., Scale formulation of firstorder nonlinear optics, Optics Communications, ISSN: 00304018, DOI: 10.1016/S00304018(96)007699, Vol.137, pp.107112, 1997 Abstract: Multidimensional propagation of a light pulse or beam in a nonlinear sample of a Kerr type is described within the firstorder optics formalism. A scale transformation that relates the nonlinear and linear propagation processes is defined by use of the nonlinear aberrationless effects. The nonlinear ray transfer matrix and Wigner distribution function are explicitly given in a factored form for the propagation of a symmetric Gaussian optical signal. An onaxis phase correction to the nonlinear firstorder formalism is also specified. Affiliations:
 
27.  Nasalski W., Aberrationless effects of nonlinear propagation, Journal of the Optical Society of America B, ISSN: 07403224, DOI: 10.1364/JOSAB.13.001736, Vol.13, No.8, pp.17361747, 1996 Abstract: For nonlinear propagation, scaled complex ray tracing [Opt. Commun. 119, 218 (1995)] in samples of Kerr media is accomplished in terms of four independent aberrationless effects: optical selfshortening, beam waist shift, waist width modification, and onaxis phase shift. A complex amplitude nonlinear modification is also introduced, and a symplectic nonlinear ABCDmatrix is determined. All the aberrationless effects are selfconsistently defined, and their dynamics are shown for focusing and defocusing nonlinearities, beam powers up to the selftrapped soliton or critical levels, and propagation ranges including those that contain a selfcollapse point. The multidimensional nature of the analysis is indicated, and its relevance to pulse compression, Zscan measurements, and higherorder mode propagation is outlined. Affiliations:
 
28.  Nasalski W., Longitudinal and transverse effects of nonspecular reflection, Journal of the Optical Society of America A, ISSN: 10847529, DOI: 10.1364/JOSAA.13.000172, Vol.13, No.1, pp.172181, 1996 Abstract: A rigorous spectral analysis is given for the nonspecular reflection of a threedimensional Gaussian beam at a dielectric isotropic planar structure. For the first time all independent nonspecular effects are derived in a selfconsistent manner for the threedimensional case. It is shown that the longitudinal nonspecular effects in the incidence plane, that is, the lateral and focal shifts of the beam waist position, the angular rotation of the reflectedbeam axis, and the modifications of the beam waist width and complex amplitude, have their direct analogies in the plane transverse to the incidence and interface planes that gives transverse nonspecular effects. Moreover, the existence of the other, not yet reported, effect of nonspecular modification of the beam polarization is also proved. A role for TM and TE polarizations in reflectedbeam formation is indicated. The results show that, up to the symmetric secondorder terms in approximation of Fresnel coefficients, each of the longitudinal and transverse beam factors independently preserves its shape under reflection at the expense of changes of the beam reference frame, width, amplitude, and polarization parameters Affiliations:
 
29.  Burak D., Nasalski W., Excitation of Optical Solitons by Higherorder HermiteGaussians, Prace IPPT  IFTR Reports, ISSN: 22993657, No.12, pp.133, 1995  
30.  Nasalski W., Complex ray tracing of nonlinear propagation, Optics Communications, ISSN: 00304018, DOI: 10.1016/00304018(95)00186C, Vol.119, pp.218226, 1995 Abstract: A new scale transformation of complex ray parameters is introduced in an unified manner to treat the nonlinear propagation in Kerr media. It is shown that the nonlinear propagation, including soliton propagation, can be consistently traced by complex rays specific to the linear propagation with the imposed scale effects of selfshortening, selffocusing and phase selfmodification. The solution obtained is explicitly described as the propagation in a freespace modified by three propagation effects, namely, the nonlinear changes of the beam or pulse waist position, waist width and onaxis phase. A field of cylindrical symmetry and arbitrary transverse dimension is analyzed for power levels ranging from the linear propagation to the soliton selftrapping. It is shown that the method can be formulated within a frame of the nonlinear ABCD matrix formalism and specified to comply with the variational analysis of the problem. Affiliations:
 
31.  Nasalski W., Ray analysis of gaussian beam nonspecular scattering, Optics Communications, ISSN: 00304018, DOI: 10.1016/00304018(92)906414, Vol.92, No.46, pp.307314, 1992 Abstract: Gaussian beam nonspecular scattering is analysed in a framework of the complexray geometrical optics with a planar dielectric interface or multilayered configuration assumed as a model of the scattering structure. The deformation parameters of the beam are rederived and the appropriate eikonal function is defined for the regular case, i.e., excluding the angles of incidence close to any singularity of the scattering coefficient. A canonical transformation of complexray data is described and the threedimensional complexvalued raytransfer matrix of the structure is given. The interrelations between the matrix elements and the deformation parameters are described. Affiliations:
 
32.  Burak D., Nasalski W., Soliton Formation from the incident Gaussian Beam in Kerr Medium, Prace IPPT  IFTR Reports, ISSN: 22993657, No.35, pp.114, 1991  
33.  Nasalski W., Samborski W., Transfer Matrix for the Nonspecular Diffraction of Gaussian Beams, Prace IPPT  IFTR Reports, ISSN: 22993657, No.42, pp.111, 1991  
34.  Samborski W., Nasalski W., Transfer and Scattering Matrix Analyses of Reflection and Transmission at Multilayered Media, Prace IPPT  IFTR Reports, ISSN: 22993657, No.30, pp.120, 1990  
35.  Nasalski W., Niespekularne odbicie pola elektromagnetycznego na granicy dwu dielektryków (Praca habilitacyjna), Prace IPPT  IFTR Reports, ISSN: 22993657, No.32, pp.1152, 1990  
36.  Nasalski W., Nonspecular bistability versus diffraction at nonlinear hybrid interfaces, Optics Communications, ISSN: 00304018, DOI: 10.1016/00304018(90)90140O, Vol.77, No.56, pp.443450, 1990 Abstract: A gaussian beam reflection at a single interface between a linear medium and the nonlinear medium driven by electrooptical feedback is analysed by the method of the monotone iteration of gaussians. The field is described completely in terms of six independent amplitude and geometrical distortions of the reflected beam. Under certain conditions all these nonspecular reflection effects exhibit significant bistable behaviour. The limitations imposed on the nonspecular bistability by diffraction is discussed and the existence of the strong bistability in the diffusive and coupledcavity configurations is indicated. Affiliations:
 
37.  Burak D., Nasalski W., Optyczny czujnik odbiciowy  zasady działania i własności, Prace IPPT  IFTR Reports, ISSN: 22993657, No.19, pp.125, 1989  
38.  Nasalski W., Macierz rozpraszania dla skokowych nieciągłości falowodów planarnych, Prace IPPT  IFTR Reports, ISSN: 22993657, No.9, pp.125, 1988  
39.  Nasalski W., Nonspecular Reflection Phenomena at Linear Dielectric Interfaces, Prace IPPT  IFTR Reports, ISSN: 22993657, No.48, pp.135, 1988  
40.  Nasalski W., Metoda WieneraHilberta w analizie skokowych nieciągłości falowodów otwartych, Prace IPPT  IFTR Reports, ISSN: 22993657, No.6, pp.132, 1986  
41.  Nasalski W., The Exact Surface Impedance Approach to Problems of Diffraction in Open Waveguides, Prace IPPT  IFTR Reports, ISSN: 22993657, No.2, pp.123, 1984  
42.  Nasalski W., Analiza modowa pola elektromagnetycznego planarnych falowodów anizotropowych, Prace IPPT  IFTR Reports, ISSN: 22993657, No.22, pp.123, 1982  
43.  Nasalski W., Dyfrakcja fali niejednorodnej na półpłaszczyźnie impedancyjnej, Prace IPPT  IFTR Reports, ISSN: 22993657, No.16, pp.124, 1980  
44.  Nasalski W., Dyfrakcja elektromagnetycznych fal powierzchniowych na półpłaszczyźnie impedancyjnej, Prace IPPT  IFTR Reports, ISSN: 22993657, No.32, pp.128, 1980  
45.  Juszkiewicz A.^{♦}, Nasalski W., Cieczowy przetwornik akustooptyczny w holografii ultradźwiękowej, Prace IPPT  IFTR Reports, ISSN: 22993657, No.50, pp.144, 1978  
46.  Nasalski W., Zewnętrzne źródła termiczne w kwantowej teorii sprężystości, Prace IPPT  IFTR Reports, ISSN: 22993657, No.30, pp.158, 1977 
List of recent monographs
1. 584  Jain A., Roszkiewicz A., Nasalski W., A note on optical materials for photolithography applications, IPPT Reports on Fundamental Technological Research, 3, pp.141, 2018 
2. 75  Nasalski W., Optical beams at dielectric interfaces  fundamentals, Trends in Mechanics of Materials, IPPT PAN, pp.1282, 2007 
Conference papers
1.  Roszkiewicz A., Nasalski W., Unidirectional surface plasmon polariton excitation at asymmetrical periodic metallodielectric multilayers, Conference on Nanophotonics IV, 20120415/0419, Brussels (BE), DOI: 10.1117/12.921798, Vol.8424, pp.842426111, 2012 Abstract: A new configuration of the onedimensional reflective asymmetrical metallodielectric grating structure for unidirectional excitation of surface plasmon polaritons (SPPs) is proposed. The structure is embedded between two different dielectric media and composed of two 1D metallic gratings each of the two consisted of periodically placed rectangular metal stripes. The case of normal incidence is analysed. It is shown that even a small horizontal shift between these two layers or a change in dielectric contrast of the grating fillings, the structure may redirect an energy flow of the SPP in the near field. An explanation of this unidirectional SPP excitation is given. Besides the SPP excitation by a plane wave, the excitation by a finitediameter 3D Gaussian beam is analysed as well, as the beam facilitates visualisation of the SPP finite propagation length and efficiency of the directivity switch. It is shown that the switching phenomenon exists together with a high concentration of the electromagnetic field at the structure, the feature especially desirable in techniques of subwavelength nanovisualisation. The configurations analysed may be also useful in designing optical devices as optical switches, VLSI devices, light harvesting photodetector structures or, in general, in any case where efficient control of energy propagation directivity is of primary importance. Keywords:Surface plasmon polaritons, planar metallic gratings, plasmonic structures, unidirectional excitation and propagation Affiliations:
 
2.  Szabelak W., Nasalski W., Excitation of optical vortices at a dielectric interface versus a beam incidence angle, 16th PolishSlovakCzech Optical Conference on Wave and Quantum Aspects of Contemporary Optics, 20080808/0812, Polanica Zdrój (PL), DOI: 10.1117/12.822386, Vol.7141, pp.7141151, 2008 Abstract: Behaviour of Laguerre{Gaussian beams (optical vortices are their attributes) impinged at a dielectric interface under distinct angles is discussed. For different incident angles the beams interact with the interface differently. Two ranges of incident angles, specified by diverse optical vortices excitation which is caused by crosspolarization effect, is analyzed. "Significant" boundary between these two ranges is defined. Theoretical analyses are confirmed by numerical simulations. Affiliations:
 
3.  Nasalski W., Pagani Y., Crosspolarization coupling of LaguerreGaussian beam modes at isotropic interfaces, Conference on Nanophotonics, 20060403/0405, Strasbourg (FR), DOI: 10.1117/12.663040, Vol.6195, pp.61950L, 2006 Abstract: Excitation and cancellation of higherorder elegant HermiteGaussian and LaguerreGaussian beams under normal incidence at isotropic, lossless, dielectric interfaces are analysed. It is shown that such phenomena are originated in the crosspolarization coupling between orthogonal polarization components of the beams and depend qualitatively on interrelations between beam field spatial distribution and beam polarization. For LagueffeGaussian beams these interrelations associate beam orbital and spin angular momenta. Analytic description confirmed by numerical simulations is given for transmission of two types of beams: HermiteGaussians of linear polarization and LagueffeGaussians of circular polarization. Keywords:refraction, reflection, crosspolarization, elegant HermiteGaussian and LaguerreGaussian beams Affiliations:
