Slow and fast surface electromagnetic waves in planar structures contained left-handed material

It was studied the properties of electromagnetic surface waves in left-handed material slab bounded by two semi-infinite nonmagnetic media with frequency dependent positive permittivity. It was assumed that all these media are isotropic and non-dissipative. It was shown that the phase velocities of...

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Published in:Вопросы атомной науки и техники
Date:2015
Main Authors: Galaydych, V.K., Azarenkov, N.A., Olefir, V.P., Sporov, A.E.
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Language:English
Published: Національний науковий центр «Харківський фізико-технічний інститут» НАН України 2015
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Cite this:Slow and fast surface electromagnetic waves in planar structures contained left-handed material / V.K. Galaydych, N.A. Azarenkov, V.P. Olefir, A.E. Sporov // Вопросы атомной науки и техники. — 2015. — № 4. — С. 306-309. — Бібліогр.: 6 назв. — англ.

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Digital Library of Periodicals of National Academy of Sciences of Ukraine
_version_ 1859518246072352768
author Galaydych, V.K.
Azarenkov, N.A.
Olefir, V.P.
Sporov, A.E.
author_facet Galaydych, V.K.
Azarenkov, N.A.
Olefir, V.P.
Sporov, A.E.
citation_txt Slow and fast surface electromagnetic waves in planar structures contained left-handed material / V.K. Galaydych, N.A. Azarenkov, V.P. Olefir, A.E. Sporov // Вопросы атомной науки и техники. — 2015. — № 4. — С. 306-309. — Бібліогр.: 6 назв. — англ.
collection DSpace DC
container_title Вопросы атомной науки и техники
description It was studied the properties of electromagnetic surface waves in left-handed material slab bounded by two semi-infinite nonmagnetic media with frequency dependent positive permittivity. It was assumed that all these media are isotropic and non-dissipative. It was shown that the phase velocities of waves are greater than the speed of light, and the group velocities are zero or negative. Вивчені властивості поверхневих електромагнітних хвиль, що поширюються уздовж шару лівостороннього матеріалу, обмеженого двома напівнескінченими немагнітними середовищами з додатними діелектричними проникностями, що залежать від частоти. Вважалось, що всі середовища є ізотропними та в них відсутні втрати. Показано, що фазові швидкості розглянутих хвиль можуть бути більше швидкості світла, а групові – нульовими або від’ємними. Изучены свойства поверхностных электромагнитных волн, распространяющихся вдоль слоя левостороннего материала, ограниченного двумя полубесконечными немагнитными средами с положительными диэлектрическими проницаемостями, зависящими от частоты. Предполагалось, что все среды являются изотропны и в них отсутствуют потери. Показано, что фазовые скорости рассматриваемых волн могут быть больше скорости света, а групповые – нулевыми или отрицательными.
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fulltext ISSN 1562-6016. ВАНТ. 2015. №4(98) 306 SLOW AND FAST SURFACE ELECTROMAGNETIC WAVES IN PLANAR STRUCTURES CONTAINED LEFT-HANDED MATERIAL V.K. Galaydych, N.A. Azarenkov, V.P. Olefir, A.E. Sporov V.N. Karazin Kharkiv National University, Kharkov, Ukraine E-mail: viktor.galaydych@gmail.com It was studied the properties of electromagnetic surface waves in left-handed material slab bounded by two semi- infinite nonmagnetic media with frequency dependent positive permittivity. It was assumed that all these media are isotropic and non-dissipative. It was shown that the phase velocities of waves are greater than the speed of light, and the group velocities are zero or negative. PACS: 52.35g, 52.50.Dg INTRODUCTION A great amount of papers devoted to the studies of modern artificial materials (metamaterials or left- handed materials, LHM) were published after first pub- lications [1, 2]. These papers were mainly devoted to the optical applications of LHM. But it is necessary to mention the studies carried out at the Argonne Wakefield Accelerator Facility; devoted to the investi- gation of the application of LHM to control the disper- sion relation in a loaded waveguide [3, 4]. Very often the planar waveguide structures that con- tain LHM are embedded either by vacuum or by differ- ent ordinary dielectrics with constant permittivity [5, 6]. The presence of ordinary dielectrics leads to the narrow- ing of possible wavenumbers range for the eigen surface electromagnetic waves of such structures as compared with vacuum bounds. In the present work it was considered the planar waveguide structure that consists of the left-handed metameterial slab bounded by two non-magnetic plas- ma-like media which permittivity depends on the wave frequency and may take the value in the range from 0 to 1. 1. TASK SETTINGS Let us consider the eigen electromagnetic waves that propagate along the planar waveguide structure that contains isotropic LHM slab of thickness ∆ . This LHM is characterized by effective permittivity and permeabil- ity which depend on the wave frequency as follow [2]: 2 2 1)( ω ω ωε p−= , (1) 2 0 2 2 1)( ωω ωωµ − −= F , (2) here pω is effective plasma frequency, 0ω is the char- acteristic frequency of LHM. In the further study we consider the LHM with / 2 10pω π = GHz, 0 / 2 4ω π = GHz and parameter 0.56F = [5]. This LHM slab is bounded on the both sides by two different artificial non-dissipative non-magnetic ( 1,2 1µ = ) materials with effective permittivities 2 1 1 2( ) 1 pω ε ω ω = − , (3) 2 2 2 2( ) 1 pω ε ω ω = − , (4) here 1pω , 2pω is the effective plasma frequencies for corresponding media. In out study we consider that 1 / 2 2,4pω π = GHz and 2 / 2 3,2pω π = GHz. Such choice of parameters leads to the existence of the fre- quency range where ( ) 0ε ω < and ( )1,20 1ε ω< < sim- ultaneously. Let restrict our consideration by the surface electro- magnetic wave that propagates along this structure. Be- sides, it is assumed that all wave components tend to zero far away from LHM and possess the dependence on time t and coordinate z in such form: 3, ( ), ( ) exp[ ( )]E H E x H x i k z tω∝ − , (5) here x is the coordinate transversal to the wave propa- gation. The system of Maxwell equations splits into two subsystems that describe the waves of H - type and E - type. The wave of E -type possesses the dispersion rela- tion of the following form: ( ) ( ) ( ) ( ) ( ) ( ) ( ) 2 1 1 2 2 2 1 2 1 2[ ] tanh 0 h h h h ε ω κ ε ω ε ω ε ω ε ω ε ω κ κ + +   + ⋅ ∆ = , (6) here, ( )2 2 1,2 3 1,2 1,2h k kε ω µ= − , ( ) ( ) 22 3 kk ωµωεκ −= , ck /ω= , c is the speed of light in vacuum. For E-wave the wave field components normalized by the )0(yH in the region of LHM can be written as: ( ) xx y eCeCxH κκ −+= 21 , ( ) ( ) ( )( )ωεκκ keCeCkxE xx x /213 −+= , (7) ( ) ( ) ( )( )ωεκ κκ keCeCixE xx z /21 −−= , here 1C and 2C are wave field constants. In first medium (3) the E-wave field components, normalized by )0(yH , possess the form: ( ) 1 ,h x yH x e= ( ) ( )1 3 1/ ,h x xE x k e k ε= (8) ( ) ( )1 1 1/ .h x zE x ih e k ε= In second plasma-like medium (4) the E-wave field components, normalized by )0(yH , can be written as: ( ) 2h x yH x Ae−= , ( ) ( )( )2 3 2/h x xE x Ak e k ε ω−= , (9) ( ) ( )( )2 2 2/h x zE x i A h e k ε ω−= − , here A is wave field constant. These constants are of ISSN 1562-6016. ВАНТ. 2015. №4(98) 307 the following form: ( ) ( ) ( )2 1 2 12 ( ) / ( )h EA h e κε ω ε ω ε ω+ ∆= − Ψ , ( ) ( )1 1 2 2 1( ) ( ) / ( ) EC h hε ω ε ω ε ω κ ε ω κ= − Ψ   , (10) ( ) ( )2 2 1 2 2 1( ) ( ) / ( ) ,EC h h e κε ω ε ω ε ω κ ε ω κ∆= − + Ψ   ( )2 2 2 2( 1) ( ) ( 1)E e h eκ κε ω ε ω κ∆ ∆Ψ = + + − . The wave of H-type possesses the dispersion relation of the following form: ( ) ( ) ( ) ( ) 2 1 1 2 2 2 1 2 1 2[ ] tanh 0. h h h h µ ω κ µ µ µ ω µ µ κ κ + + + ∆ = (11) In the region of LHM slab the H-wave field compo- nents, normalized by the )0(yE , can be written as: ( ) 1 2 x x yE x D e D eκ κ−= + , ( ) ( ) ( )( )3 1 2 /x x xH x k D e D e kκ κ µ ω−= − + , (12) ( ) ( ) ( )( )1 2 /x x zH x i D e D e kκ κκ µ ω−= − − , here 1D and 2D are wave field constants. In the first medium the H-wave field components, normalized by the )0(yE , can be expressed as: ( ) xh y exE 1= , ( ) ( )13 /1 µkekxH xh x −= , (13) ( ) ( )11 /1 µkeihxH xh z −= . In the second plasma-like half-space the H-wave field components, normalized by )0(yE , can be written as: ( ) xh y BexE 2−= , ( ) ( )23 /2 µkeBkxH xh x −−= , (14) ( ) ( )22 /2 µkehBixH xh z −= , here B is wave field constant. These constants are of the following form: ( ) ( )2 1 2 12 ( ) /h HB h e κµ µ ω µ+ ∆= − Ψ , ( )1 1 2 2 1( ) ( ( ) ) / HD h hµ ω µ ω µ κ µ κ= − Ψ , (15) ( )2 2 1 2 2 1( ) ( ( ) ) / HD h h e κµ ω µ ω µ κ µ κ∆= − + Ψ , 2 2 2 2( 1) ( ) ( 1)H e h eκ κµ ω µ κ∆ ∆Ψ = + + − . 2. MAIN RESULTS The numerical solutions of dispersion relations (6) and (11) for E - and H -waves are presented at the Fig. 1. Numbers of curves 1, 2 correspond to the waves of H -type and curves marked by the numbers 3, 4 cor- respond to the waves of E -type. It is important to notice that the central metamaterial slab demonstrates left-handed properties ( 0)( <ωε and 0)( <ωµ simultaneously) for the normalized frequency 01 / 1,5ω ω< Ω = < . The letters on the Fig. 1a,b,c cor- respond to the curves ( )2ξ ε ω= Ω , ( )1ξ ε ω= Ω , ( ) ( )ξ ε ω µ ω= Ω , respectively. The waves of the sur- face type can exist in the area right to the lines marked by the letters a, b and higher of line marked by the letter c. The line L corresponds to the light in vacuum, i.e. ξ = Ω . Fig. 1. The dependence of the normalized frequency 0/ωω=Ω on the dimensionless wave number 3 0/k cξ ω= at the thickness 0 / 2cω ∆ = for H1,2-modes (lines 1, 2) and E1,2 -modes (lines 3, 4) Further we shall study the dependence of phase 3/phV kω= and group 3grV d dkω= velocities on the problem’s parameters. Now, the Fig. 1 shows that three modes can have phase velocity higher than light speed in vacuum. Phase velocities of both 1,2E -modes (see curves 3, 4 of the Fig. 1) monotonously decreases with the increase of wave frequency. They do not change qualitatively its behavior with the increase of thickness of LHM layer (see Fig. 2). Phase velocity of 2H -mode (curve 2 of the Fig. 1) monotonously increases with the increase of wave frequency and also does not change qualitatively its behavior with increasing of thickness of LHM layer. Fig. 2. The dependence of the phase velocity /phV c of E-wave (curve 3 on Fig. 1) on the frequency 0/ωω=Ω for different LHM slab thickness 0 / 0,5;1.5;2cω ∆ = But 1H -mode (see curve 1 at Fig. 1) shows qualita- tively different behavior (Fig. 3). If LHM slab thickness is rather small (see line marked by the number 0.5 at the Fig. 3) the H-wave decreases its phase velocity with the increase of wave frequency. When the LHM slab thick- ness increases its value (see lines marked by the num- bers 1.5 and 2.0 at the Fig. 3) there is a qualitative tran- sition of the behavior of phase velocity versus frequen- cy: phase velocity of the 1H -mode increases with the increase of the wave frequency. ISSN 1562-6016. ВАНТ. 2015. №4(98) 308 Fig. 3. The dependence of the phase velocity /phV c of 1H -wave (line 1 on Fig.1) on the frequency 0/ωω=Ω for different LHM slab thickness 0 / 0,5;1.5;2cω ∆ = The carried out study shows that the considered sur- face waves can be either slow or fast depending on the choice of operating frequency. It was shown that it is possible to change the phase velocity of the considered waves at fixed frequency by the variation of LHM slab thickness ∆ . Such depend- ence is called the geometric dispersion and it is present- ed on Fig. 4. Fig. 4. The dependence of the phase velocity /phV c on LHM slab thickness ∆ for: 1 – 1H -wave (see curve 2 on Fig. 1, 1,64Ω = ); 2 – 2H -wave (see curve 3 on Fig. 1, 1,23Ω = ); 3 – 1E -wave (see curve 4 on Fig. 1, 1,154Ω = ) Fig. 5. The spatial distribution of electric field wave amplitudes versus transversal coordinate x for differ- ent modes 1 – 1H -mode ( 3 4,0k = , 1,19258Ω = ) and 2 – 2H -mode ( 3 4,0k = ; 1,193586Ω = ) The normalized phase velocity for 2E -wave linearly changes from 0.5 to 3.2 at the same parameters. The dependence of electric wave field amplitude on the transversal coordinate x for the considered modes has symmetric or anti-symmetric character (for example Fig. 5). When the wavelength of the surface wave increases the penetration depth of the considered waves increases sharply, and the wave becomes essentially a bulk wave (Fig. 6). Fig. 6. The spatial distribution of electric field wave amplitudes versus transversal coordinate for 2H -mode for different wavenumber k3 = 4.0 and k3 = 1.2 Fig. 7. The dependence of the normalized group velocity /grV c on of the frequency 0/ωω=Ω for LHM slab thickness 0 / 0.5cω ∆ = (numbers of lines corresponds to the Fig. 1) It is necessary to mention, that the group velocity value of the considered waves can be either zero, or small, or high (Fig. 7). The Fig. 7 shows that the considered modes are for- ward and backward, slow and fast. It is shown that in the considered waveguide structure the H-modes with zero group velocity can exist. We supposed that such waves can be used in accelerating technology. CONCLUSIONS It was found the possibility of existence of the sur- face electromagnetic waves that propagate along the LHM planar slab that bounded by two semi-infinite plasma-like media. It was found four modes (two E-modes and two H- modes) with different wave field structure. It was shown that three modes of this four can have phase velocity higher than light speed in vacuum. It was also shown that waves considered possess both positive and negative frequency dispersion of the phase velocity. It was obtained that one of the H-waves can be backward (phase and group velocity directed opposite- ly). The absolute value of the group velocity of H-waves can be quite low, down to zero. ISSN 1562-6016. ВАНТ. 2015. №4(98) 309 It was shown that is possible to change the phase ve- locity of waves considered at fixed frequency by varia- tion of LHN slab thickness. The obtained results can be useful for the plasma electronics modeling and improvement of acceleration technology. REFERENCES 1. V.G. Veselago. The electrodynamics of substances with simultaneously negative values of ε and μ // Soviet Physics Uspekhi. 1968, v. 10, p. 509-514. 2. J.B. Pendry, A.J. Holden, W.J. Stewart, I. Youngs. Extremely low frequency plasmons in metallic mi- crostructures // Phys. Rev. Lett. 1996, v.76, p. 4773. 3. S. Antipov, W. Liu, W. Gai, J. Power, L. Spentzou- ris. Double-negative metamaterial research for ac- celerator applications // Nucl. Instr. Meth. 2007, v. A579, iss. 3, p. 915-923. 4. S. Antipov, L. Spentzouris, W. Gai, M. Conde, F. Franchini, et al. Observation of wakefield genera- tion in left-handed band of metamaterial-loaded waveguide // J. Appl. Phys. 2008, v. 104, p. 014901. 5. I.V. Shadrivov, A.A. Sukhorukov, Yu.S Kivshar. Guided modes in negative-refractive-index wave- guides // Phys. Rev. 2003, E 67, p. 057602-4. 6. V.K. Galaydych, N.A. Azarenkov, V.P. Olefir, A.E. Sporov. Surface electromagnetic waves in left- handed material slab embedded in plasma-like me- dia// Problems of Atomic Science and Technology. Series “Plasma Physics» (20). 2014, № 6, p. 112- 115. Article received 23.06.2015 МЕДЛЕННЫЕ И БЫСТРЫЕ ПОВЕРХНОСТНЫЕ ЭЛЕКТРОМАГНИТНЫЕ ВОЛНЫ В ПЛОСКИХ СТРУКТУРАХ, СОДЕРЖАЩИХ ЛЕВОСТОРОННИЙ МАТЕРИАЛ В.К. Галайдыч, Н.А. Азаренков, В.П. Олефир, А.Е. Споров Изучены свойства поверхностных электромагнитных волн, распространяющихся вдоль слоя левосторон- него материала, ограниченного двумя полубесконечными немагнитными средами с положительными ди- электрическими проницаемостями, зависящими от частоты. Предполагалось, что все среды являются изо- тропны и в них отсутствуют потери. Показано, что фазовые скорости рассматриваемых волн могут быть больше скорости света, а групповые – нулевыми или отрицательными. ПОВІЛЬНІ ТА ШВИДКІ ПОВЕРХНЕВІ ЕЛЕКТРОМАГНІТНІ ХВИЛІ В ПЛАСКИХ СТРУКТУРАХ, ЩО МІСТЯТЬ ЛІВОСТОРОННІЙ МАТЕРІАЛ В.К. Галайдич, М.О. Азарєнков, В.П. Олефір, О.Є. Споров Вивчені властивості поверхневих електромагнітних хвиль, що поширюються уздовж шару лівосторон- нього матеріалу, обмеженого двома напівнескінченими немагнітними середовищами з додатними діелект- ричними проникностями, що залежать від частоти. Вважалось, що всі середовища є ізотропними та в них відсутні втрати. Показано, що фазові швидкості розглянутих хвиль можуть бути більше швидкості світла, а групові – нульовими або від’ємними. http://ufn.ru/en/articles/1968/4/d/ http://ufn.ru/en/articles/1968/4/d/ http://www.rsphysse.anu.edu.au/nonlinear/papers/IlyaShadrivov.shtml#PRE_2003_67_57602 http://www.rsphysse.anu.edu.au/nonlinear/papers/AndreySukhorukov.shtml#PRE_2003_67_57602 http://www.rsphysse.anu.edu.au/nonlinear/papers/YuriKivshar.shtml#PRE_2003_67_57602 INTRODUCTION 1. TASK SETTINGS 2. MAIN RESULTS REFERENCES МЕДЛЕННЫЕ И БЫСТРЫЕ ПОВЕРХНОСТНЫЕ ЭЛЕКТРОМАГНИТНЫЕ ВОЛНЫ В ПЛОСКИХ СТРУКТУРАХ, СОДЕРЖАЩИХ ЛЕВОСТОРОННИЙ МАТЕРИАЛ ПОВІЛЬНІ ТА ШВИДКІ ПОВЕРХНЕВІ ЕЛЕКТРОМАГНІТНІ ХВИЛІ В ПЛАСКИХ СТРУКТУРАХ, ЩО МІСТЯТЬ ЛІВОСТОРОННІЙ МАТЕРІАЛ
id nasplib_isofts_kiev_ua-123456789-112209
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
issn 1562-6016
language English
last_indexed 2025-11-25T20:43:26Z
publishDate 2015
publisher Національний науковий центр «Харківський фізико-технічний інститут» НАН України
record_format dspace
spelling Galaydych, V.K.
Azarenkov, N.A.
Olefir, V.P.
Sporov, A.E.
2017-01-18T19:30:44Z
2017-01-18T19:30:44Z
2015
Slow and fast surface electromagnetic waves in planar structures contained left-handed material / V.K. Galaydych, N.A. Azarenkov, V.P. Olefir, A.E. Sporov // Вопросы атомной науки и техники. — 2015. — № 4. — С. 306-309. — Бібліогр.: 6 назв. — англ.
1562-6016
PACS: 52.35g, 52.50.Dg
https://nasplib.isofts.kiev.ua/handle/123456789/112209
It was studied the properties of electromagnetic surface waves in left-handed material slab bounded by two semi-infinite nonmagnetic media with frequency dependent positive permittivity. It was assumed that all these media are isotropic and non-dissipative. It was shown that the phase velocities of waves are greater than the speed of light, and the group velocities are zero or negative.
Вивчені властивості поверхневих електромагнітних хвиль, що поширюються уздовж шару лівостороннього матеріалу, обмеженого двома напівнескінченими немагнітними середовищами з додатними діелектричними проникностями, що залежать від частоти. Вважалось, що всі середовища є ізотропними та в них відсутні втрати. Показано, що фазові швидкості розглянутих хвиль можуть бути більше швидкості світла, а групові – нульовими або від’ємними.
Изучены свойства поверхностных электромагнитных волн, распространяющихся вдоль слоя левостороннего материала, ограниченного двумя полубесконечными немагнитными средами с положительными диэлектрическими проницаемостями, зависящими от частоты. Предполагалось, что все среды являются изотропны и в них отсутствуют потери. Показано, что фазовые скорости рассматриваемых волн могут быть больше скорости света, а групповые – нулевыми или отрицательными.
en
Національний науковий центр «Харківський фізико-технічний інститут» НАН України
Вопросы атомной науки и техники
Приложения и технологии
Slow and fast surface electromagnetic waves in planar structures contained left-handed material
Повільні та швидкі поверхневі електромагнітні хвилі в пласких структурах, що містять лівосторонній матеріал
Медленные и быстрые поверхностные электромагнитные волны в плоских структурах, содержащих левосторонний материал
Article
published earlier
spellingShingle Slow and fast surface electromagnetic waves in planar structures contained left-handed material
Galaydych, V.K.
Azarenkov, N.A.
Olefir, V.P.
Sporov, A.E.
Приложения и технологии
title Slow and fast surface electromagnetic waves in planar structures contained left-handed material
title_alt Повільні та швидкі поверхневі електромагнітні хвилі в пласких структурах, що містять лівосторонній матеріал
Медленные и быстрые поверхностные электромагнитные волны в плоских структурах, содержащих левосторонний материал
title_full Slow and fast surface electromagnetic waves in planar structures contained left-handed material
title_fullStr Slow and fast surface electromagnetic waves in planar structures contained left-handed material
title_full_unstemmed Slow and fast surface electromagnetic waves in planar structures contained left-handed material
title_short Slow and fast surface electromagnetic waves in planar structures contained left-handed material
title_sort slow and fast surface electromagnetic waves in planar structures contained left-handed material
topic Приложения и технологии
topic_facet Приложения и технологии
url https://nasplib.isofts.kiev.ua/handle/123456789/112209
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AT azarenkovna povílʹnítašvidkípoverhnevíelektromagnítníhvilívplaskihstrukturahŝomístâtʹlívostoronníimateríal
AT olefirvp povílʹnítašvidkípoverhnevíelektromagnítníhvilívplaskihstrukturahŝomístâtʹlívostoronníimateríal
AT sporovae povílʹnítašvidkípoverhnevíelektromagnítníhvilívplaskihstrukturahŝomístâtʹlívostoronníimateríal
AT galaydychvk medlennyeibystryepoverhnostnyeélektromagnitnyevolnyvploskihstrukturahsoderžaŝihlevostoronniimaterial
AT azarenkovna medlennyeibystryepoverhnostnyeélektromagnitnyevolnyvploskihstrukturahsoderžaŝihlevostoronniimaterial
AT olefirvp medlennyeibystryepoverhnostnyeélektromagnitnyevolnyvploskihstrukturahsoderžaŝihlevostoronniimaterial
AT sporovae medlennyeibystryepoverhnostnyeélektromagnitnyevolnyvploskihstrukturahsoderžaŝihlevostoronniimaterial