Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Method for analyzing multilayer nonlinear optical waveguide

Open Access Open Access

Abstract

We propose a novel method for analyzing a multilayer optical waveguide structure with all nonlinear guiding films. This method can also be used to analyze a multibranch optical waveguide structure with all nonlinear guiding branches. The results show that agreement between theory and numerics is excellent.

©2005 Optical Society of America

1. Introduction

Kerr-like nonlinear waveguide structures containing one or more media, whose refractive index depends on the local intensity, have stimulated a great deal of theoretical and experimental study [1–13]. The interest in nonlinear waveguide device, which has been growing steadily in recent years, stems from their potential use for ultrafast all-optical signal processing and optical computing systems. The confinement of optical beam in the small core area over long distance increase the efficiency of the nonlinear interaction and permit the use of relatively weak nonlinearities. It has been shown that these nonlinear waveguides possess a variety of novel and exciting features such as power-dependent propagation constants and field profiles leading to novel feasibilities for all-optical signal processing and optical computing.

Until now, the overwhelming majority of the published papers was aimed at analyzing the optical waveguide structures where either linear films were bounded by one or two nonlinear media [14–18] or a nonlinear film was sandwiched between linear films [19–21]. If the guiding dielectric films are all nonlinear, the solution fields are much more complex and consist of Jacobi elliptic functions [22]. Within the past several years, it became evident that the multilayer systems as semiconductor multiple quantum well structures exhibit stronger nonlinearity, low threshold power, very fast response times, and suitability for integration into circuits [23–25].

In the future, the multilayer and multibranch waveguide structures are very important components in the application of integrated optics. The multilayer waveguide structures have been extensively used in the multiple quantum well waveguide structures [26–29] and the multibranch waveguide structures have also been designed to operate as all-optical waveguide devices [30–39]. To the best of our knowledge, the general method for analyzing the multilayer optical waveguide with all nonlinear guiding films that is presented in this paper has not been reported before. This paper gives a detail modal analysis of the multilayer optical waveguide with all nonlinear guiding films. The analytical results are accompanied by numerical examples. This method can also be used to predict the evolution of a wave propagating along the multibranch optical waveguide structure with all nonlinear guiding branches. The numerical results show that our analyses are correct.

2. Analysis process

In this section, we use the modal theory [40–41] to derive the general formulas that can be used to analyze the multilayer optical waveguide structure with all nonlinear guiding films, as shown in Fig. 1. The multilayer optical waveguide structure is composed of nonlinear guiding films (m12layers), interaction layers (m32layers), cladding, and substrate. The total number of layers is m (m = 3,5,7,…). The cladding and substrate layers are assumed to extend to infinity in the +x and -x direction, respectively. The major significance of this assumption is that there are no reflections in the x direction to be concerned with, except for those occurring at interfaces.

 figure: Fig. 1.

Fig. 1. The structure of multilayer optical waveguides with all nonlinear guiding films.

Download Full Size | PDF

For simplicity, we consider the transverse electric polarized waves propagating along the z direction. The wave equation can be reduced to

2Eyi=ni2c22Eyit2,i=1,2,,m

with solutions of the form

Eyixzt=εi(x)exp[j(ωtβk0z)]

where ω is the angular frequency, k 0 is the wave number in the free space, and β is the effective refractive index. For a Kerr-type nonlinear medium [42–44], the square of the refractive index of the guiding film can be expressed as

ni2=n0i2+αiεi(x)2,i=2,4,,m1

where n 0i and αi are the linear refractive index and the nonlinear coefficient of the i-th layer nonlinear guiding film, respectively. The transverse electric field in each layer can be expressed as:

ε1(x)=Esexp(p1x)in the substrate
εi(x)=EI(i2)exp{pi[x(i12)d(i32)w]}+EI(i1){exppi[x(i12)d(i12)w]}
i=3,5,,m2in the interaction layers
εi(x)=bicn{Ai[x(i21)(d+w)+x0i]li}
i=2,4,,m1intheguidingfilm,forβ<ni
εi(x)=bi¯cn{Ai¯[x(i21)(d+w)+x̅0i]li¯}
i=2,4,,m1intheguidingfilm,forβ>ni
εm(x)=Ecexp{pm[x(m12)d(m32)w]}in the cladding

where cn is a Jacobian elliptic function, and the constants d and w are the widths of the guiding film and the interaction layer, respectively.

The constants pi, bi, Ai, li, i, i, and i. can be expressed as

pi=k0β2ni2,
bi2=qi4+2αik02Kiqi2αik02,
Ai=[(ai2+bi2)(αik022)]12,
li=bi2(ai2+bi2),
b̅i2=Qi4+2αik02Ki+Qi2αik02,
A̅i=[(a̅i2+b̅i2)(αik022)]12,
l̅i=b̅i2(a̅i2+b̅i2),

where the constants ai, i, qi , Qi, Ki, x 0i and x0i̅ are shown in the Appendix. For simplicity, the modulus li and i are omitted in the following discussions.

Considering the case β<ni (i = 2,4,…,m-1) and matching the boundary conditions, we can obtain the following eigenvalue equations:

for m ≤ 7 ,

[cn(Am1d)Δm2++sn(Am1d)dn(Am1d)pm2Δm2Am1][1lm1(1Δm2+2bm12)sn2(Am1d)]Am1={Δm2+[1lm1(1Δm2+2bm12)sn(Am1d)dn(Am1d)]Δm2+lm1(1Δm2+2bm12)sn(Am1d)cn2(Am1d)dn(Am1d)+pm2Δm2Am1[cn(Am1d)dn2(Am1d)lm1Δm2+2bm14sn2(Am1d)cn(Am1d)]}[1lm1(1Δm2+2bm14)sn2(Am1d)]2pm,
whereΔm2+=EI(m4)exp(pm2w)+EI(m3),
Δm2=EI(m4)exp(pm2w)EI(m3).
EcP3A2b2={Esb2[1l2(1Es2b22)]sn(A2d)dn(A2d)l2Esb2(1Es2b22)sn(A2d)cn2(A2d)dn(A2d)Esp1b2A2[cn(A2d)dn2(A2d)l2Es2b22sn2(A2d)cn(A2d)]}[EsEccn(A2d)+Esp1EcA2sn(A2d)dn(A2d)]2,
form=5,
[Δ3+cn(A4d)p3Δ3A4sn(A4d)dn(A4d)][1l4(1Δ3+2b42)sn2(A4d)]A4={Δ3+[1l4(1Δ3+2b42)]sn(A4d)dn(A4d)Δ3+l4(1Δ3+2b42)sn(A4d)dn(A4d)cn2(A4d)}+p3Δ3A4cn(A4d)[dn2(A4d)l4Δ3+2b42sn2(A4d)][1l4(1Δ3+2b42)sn2(A4d)]2p5,
whereΔ3+=EI1exp(p3w)+EI2,
Δ3=EI1exp(p3w)+EI2,

and sn and dn are Jacobi elliptic functions. These eigenvalue equations (9)–(11) can be solved by a numerical method on a computer. A diagram indicating the computation step is shows in Fig. 2. When the constants β and Es are determined, all the other constants qi, pi, Ki, Ai, ai, bi, li, x 0i, Eli, and Ec are also determined (Appendix).

 figure: Fig. 2.

Fig. 2. Diagram of the computation steps (9)–(11)

Download Full Size | PDF

For the case β > ni (ni = 2,4,…,m-1), on the other hand, we just have to replace the constants Ai, ai, bi, li, and x 0i in Eqs.(9)–(11) with the constants i, i, i, i, and x 0i̅, and get these equations with similar expressions. When constants β and Es are determined, all the other constants Qi, pi, Ki, i, i, i, i, x 0i̅, EIi, and Ec are also determined (Appendix).

3. Numerical results and discussion

In this section, we use the formulas derived in the preceding section and in the Appendix to calculate the transverse electric field function in each layer of the multilayer optical waveguide structure with all nonlinear guiding films. Several numerical examples are presented as follows. When m=3, the formulas can be used to analyze the three-layer optical waveguide structure with nonlinear guiding film. The numerical results are shown in Figs. 3(a) and (b). Figure 3(a) shows a dispersion curve of TE 0 symmetric modes of the three-layer nonlinear optical waveguide structure with the constants d = 3μm, n 1 = n 3 =1.55, n 02 =1.57 , α = 6.3786μm 2 /V 2 (for MBBA Liquid Crystal), and the free space wavelength is λ = 1.3μm . Figure 3(b) shows the electric field distributions for the various input powers with respect to points A-D as shown in Fig. 3(a). When m = 5, the formulas can be used to analyze the five-layer optical waveguide structure with all nonlinear guiding film. The numerical results are shown in Figs. 4(a) and (b). Figure 4(a) shows a dispersion curve of TE 0 symmetric modes of the five-layer nonlinear optical waveguide structure with the constants d = 3μm , w = 7μm , n 1 = n 3 = n 5 = 1.55 , n 02= n 04 = 1.57 , α = 6.3786μm 2/V 2, and λ = 1.3μm. Figure 4(b) shows the electric field distributions for the various input powers with respect to points A-D as shown in Fig. 4(a). When m = 7 , we can simplify the general formulas to analyze the seven-layer optical waveguide structure with all nonlinear guiding films. The numerical results are shown in Figs. 5(a) and (b). Figure 5(a) shows a dispersion curve of TE 0 symmetric modes of the seven-layer nonlinear optical waveguide structure with the constants d = 3μm, w = 7μm , n 1 = n 3 = n 5 = n 7 =1.55 , n 02 = n 04 = n 06 = 1.57 , α = 6.3786μm 2 /V 2 , and λ = 1.3μm. Figure 5(b) shows the electric field distributions for the various input powers with respect to points A-D as shown in Fig. 5(a). As the results shown in Figs. 3–5, as the guided power increases and consequently β increases, the field distributions gradually narrow, and the optical wave will be tightly confined in the center nonlinear guiding film.

 figure: Fig. 3.

Fig. 3. (a)Dispersion curve of the three-layer optical waveguide structure with the nonlinear central guiding film. (b)The electric field distributions with respect to points A-D as shown in (a).

Download Full Size | PDF

 figure: Fig. 4.

Fig. 4. (a)Dispersion curve of the five-layer optical waveguide structure with the nonlinear central guiding film. (b)The electric field distributions with respect to points A-D as shown in (a).

Download Full Size | PDF

 figure: Fig. 5.

Fig. 5. (a)Dispersion curve of the seven-layer optical waveguide structure with the nonlinear central guiding film. (b)The electric field distributions with respect to points A-D as shown in (a).

Download Full Size | PDF

We can also use these formulas to analyze the multibranch optical waveguide structure with all nonlinear guiding branches, as shown in Fig. 6. In the following analysis the multibranch optical waveguide structure is divided into four sections from bottom to top: the straight-line section (three-layer waveguide), the tapered section (three-layered tapered waveguide), the nonlinear multibranch section (multilayer waveguides with tapered interaction layers), and the isolated separating section (multilayer waveguides isolated from one another). The tapered-waveguide section and the separating-waveguide section can be approximated by straight waveguide segments step by step [40,41]. These step-waveguide segments can be analyzed by the method proposed in the preceding section. For simplicity, the symbol N is used to denoted the nonlinear medium. We can use this method to predict the evolution of a wave propagating along the multibranch waveguide structure with all nonlinear guiding branches. Here we show an example of a three-branch waveguide structure with all nonlinear guiding branches, as shown in Fig. 7. We discuss the low input power density and the high input power density cases, respectively.

 figure: Fig. 6.

Fig. 6. The multibranch optical waveguide structure with all nonlinear guiding branches (N denoted the nonlinear medium).

Download Full Size | PDF

 figure: Fig. 7.

Fig. 7. The three-branch optical waveguide structure with all nonlinear guiding branches (N denoted the nonlinear medium).

Download Full Size | PDF

For the low input power density case, the electric field distributions of the four sections (positions Z 1, Z 2, Z 3, Z 4 in Fig. 7) are shown in Figs. 8(a)–(d), respectively. In Fig. 8(a) the electric field distribution of the straight waveguide section is plotted with the constants d =3μm , nc = ns = nI =1.55 , n f0 = 1.57 , β = 1.5654 , α = 6.3786μm 2/V 2 , and λ = 1.3μm. In Fig. 8(b) the electric field distribution of the straight waveguide section is plotted with the constants d =6μm , nc = ns = nI = 1.55 , n f0 =1.57 , β = 1.5654 , α = 6.3786μm 2 /V 2 , and λ = 1.3μm. In Fig. 8(c) the electric-field distribution of the coupled separating-waveguide section is plotted with d =3μm , w = 5μm, nc = ns = nI = 1.55 , n f0 = 1.57, β = 1.5655 , α = 6.3786μm 2/V 2, and λ = 1.3μm. And in Fig. 8(d) the electric-field distribution of the isolated separating- distribution of the isolated separating-waveguide section is plotted with d = 3μm, w = 7μm, nc = ns = nI = 1.55 , n f0 = 1.57 , β = 1.56545 , α = 6.3786μm 2/V 2 , and λ = 1.3μm.

 figure: Fig. 8.

Fig. 8. For the low input power density case, electric-field distributions of the three-branch optical waveguide structure with all nonlinear guiding branches at positions (a)Z1 (df = 3μm , β = 1.5654), (b)Z2 (df = 6μm, β = 1.5654), (c)Z3 (df = 3μm , dI = 5μm , β = 1.5655), (d)Z4 (df = 3μm , dI = 7μm, β = 1.56545).

Download Full Size | PDF

For the high input power density case, the electric field distributions of the four sections (positions Z 1, Z 2, Z 3, Z 4 in Fig. 7) are shown in Figs. 9(a)–(d), respectively. In Fig. 9(a) the electric field distribution of the straight waveguide section is plotted with the constants d = 3μm , nc = ns = nI = 1.55 , n f0 =1.57 , β = 1.56925 , α = 6.3786μm 2/V 2 , and λ = l.3μm. In Fig. 9(b) the electric field distribution of the straight waveguide section is plotted with the constants d =6μm , nc = ns = nI = 1.55 , n f0 = 1.57 , β = 1.56925 , α = 6.3786μm 2/V 2 , and λ = 1.3μm. In Fig. 9(c) the electric-field distribution of the coupled separating-waveguide section is plotted with d =3μm , w = 5μm , nc = ns = nI = 1.55 , n f0 = 1.57, β = 1.5690 , α = 6.3786μm 2/V 2 , and λ = 1.3μm . And in Fig. 9(d) the electric-field distribution of the isolated separating-waveguide section is plotted with d = 3μm, w = 7μm , nc = ns = nI = 1.55 , n f0 = l.51 , β = 1.5693 , α = 6.3786μm 2/V 2, and λ = l.3μm.

 figure: Fig. 9.

Fig. 9. For the high input power density case, electric-field distributions of the three-branch optical waveguide structure with all nonlinear guiding branches at positions (a)Z1 (df = 3μm , β = 1.56925), (b)Z2 (df = 6μm, β = 1.56925), (c)Z3 (df = 3μm , dI = 5μm, β = 1.5690), (d)Z4 (df = 3μm, dI = 7μm, β = 1.5693).

Download Full Size | PDF

To prove the accuracy of the results shown in Figs. 8 and 9, we use the beam propagation method [45] to simulate the electric field propagating along this structure, from the stem to the branching waveguides. For the calculation we choose the following numerical data: the transverse sampling points N = 4096 , the longitudinal step length Δz = 0.05μm, the total propagation distance Z =1500μm , and the branching angle θ = 0.573°. The simulation results for the low input power density and high input power density cases are shown in Figs. 10 and 11. The relevant curves shown in Figs. 8–9 and Figs. 10–11 are superposed on the same graph shown in Figs. 12–13. By comparing the results shown in Figs. 8–9 and Figs. 10–11, we confirm that our analyze are correct.

 figure: Fig. 10.

Fig. 10. The typical evolution of a wave propagating along a three-branch optical waveguide structure with all nonlinear guiding branches at the low input power density.

Download Full Size | PDF

 figure: Fig. 11.

Fig. 11. The typical evolution of a wave propagating along a three-branch optical waveguide structure with all nonlinear guiding branches at the high input power density.

Download Full Size | PDF

 figure: Fig. 12.

Fig. 12. The relevant curves shown in Figs. 6 and 8 on the same graph (a) at position Z1, (b) at position Z2, (c) at position Z3, (d) at position Z4. (┄:the predicted results;―: the numerical simulation results).

Download Full Size | PDF

 figure: Fig. 13.

Fig. 13. The relevant curves shown in Figs. 7 and 9 on the same graph (a) at position Z1, (b) at position Z2, (c) at position Z3, (d) at position Z4. (┄:the predicted results;―: the numerical simulation results).

Download Full Size | PDF

4. Conclusions

In this paper, we propose a novel method for analyzing the multilayer optical waveguide structure with all nonlinear guiding films. This method can also be used to predict the evolution of waves propagating along the multibranch optical waveguide structure with all nonlinear guiding branches. We give a detail modal analysis of the proposed nonlinear optical waveguide structure. The analytical results are accompanied by numerical examples. The numerical simulation results show that our analyses are correct.

Appendix

ai2=qi4+2αik02Ki+qi2αik02,
a̅i2=qi4+2αik02KiQi2αik02,
Ai=[(ai2+bi2)(αik022)]12,
A̅i=[(a̅i2+b̅i2)(αik022)]12,
qi2=k0(ni2β2),forβ<ni(ni=2,4,,m1),
Qi2=k0(β2ni2),forβ>ni(ni=2,4,,m1),
EI1=12{[Escn(A2d)+p1EsA2sn(A2d)dn(A2d)][1l2sn2(A2d)(1Es2b22)]}+A2{Essn(A2d)dn(A2d){[1l2(1Es2b22)]l2(1Es2b22)cn2(A2d)}p1EsA2cn(A2d)[dn2(A2d)l2Es2b22sn2(A2d)]p3[1l2sn2(A2d)(1Es2b22)]2},
EIi=12{[Δi2+cn(Ai+1d)+pi2Δi2Ai+1]sn(Ai+1)dn(Ai+1d)[1li+1(1Δi2+2bi+12)sn2(Ai+1d)]+Ai+1{Δi2+[1li+1(1Δi2+2bi+12)][1li+1cn2(Ai+1)]sn(Ai+1d)dn(Ai+1d)Δi2+li+1(1Δi2+2bi+14)sn(Ai+1d)cn2(Ai+1d)dn(Ai+1d)Δi2pi2Ai+1cn(Ai+1d)[dn2(Ai+1d)li+1Δi2+2bi+12sn2(Ai+1d)]}[1li+1sn2(Ai+1d)(1Δi2+2bi+14)]2pi},i=3,5,m2,
whereΔi2+=EIi2+EIi1exp(pi2w),
Δi2=EIi2EIi1exp(pi2w).
Fori=4,6,m3,
x0i=1Aicn1(EI(i3)exp(p(i1)w)+EI(i2)bi),
x̅0i=1Ai¯cn1(EI(i3)exp(p(i1)w)+EI(i2)bi¯),
Ki=k02EI(i1)2(ni2ni+12+αiEI(i1)22)+k02EIi2exp(2p(i+1)w)[ni2ni+12+αiEIi22exp(2p(i+1)w)]
+2EI(i1)EIik02exp(p(i+1)w)[ni22β2+ni+12+32αiEI(i1)EIiexp(p(i+1)w)]
+2αiEI(i1)EIik02exp(p(i+1)w)[EI(i1)2+EIi2exp(2p(i+1)w)].

Otherwise,

x02=1A2cn1(E0b2),
x0m1=1Am1cn1(E0bm1)d,
x̅02=1A2¯cn1(E0b̅2),
x̅0m1=1A̅m1cn1(E0b̅m1)d,
K2=k02E02(n22n12+α2E022),
Km1=k02Em2(nm12nm2+α(m1)Em22).

Acknowledgments

The author thanks Jyh-Shiuan Lin and Dong-Heng Cai for his helpful discussions and support in this work.This work was supported by National Science Council, R.O.C. under Grant No. 94-2215-E-151 -001.

References and links

1. G. I. Stegeman, C. T. Seaton, J Chilwell, and S. D. Smith, “Nonlinear waves guided by thin films,” Apply. Phys. Lett. 44, 830 (1984). [CrossRef]  

2. A. D. Boardman and P. Egan, “Optically nonlinear waves in thin films,” IEEE J. Quantum Electron. 22, 319 (1986). [CrossRef]  

3. A. D. Boardman and P. Egan, “Nonlinear surface and guided polaritions of a general layered dielectric structure,” J. Phys. Colloq. C5, 291 (1984).

4. N. N. Akhmediev, “Novel class of nonlinear surface waves: Asymmetric modes in a symmetric layered structure,” Sov. Phys. -JETP. 56, 299 (1982).

5. F. Lederer, U. Langbein, and H. E. Ponath. “Nonlinear waves guided by a dielectric slab,” Appl. Phys. B. 31, 187 (1983). [CrossRef]  

6. U. Langbein, F. Lederer, H.-E. Ponath, and U. Trutschel, “Dispersion relations for nonlinear guided waves,” J. Mol. Struct. 115, 493 (1984). [CrossRef]  

7. D. Mihalache and H. Totia, “S-polarized nonlinear surface and guided waves in an asymmetric layered structure,” Rev. Roumaine Phys. 29, 365 (1984).

8. D. J. Robbins, “TE modes in a slab waveguide bounded by nonlinear media,” Opt. Commun. 47, 309 (1983). [CrossRef]  

9. U. Langbein, F. Lederer, and H. E. Ponath, “A new type of nonlinear slab-guided wave,” Opt. Commun. 46, 167 (1983). [CrossRef]  

10. F. Fedyanin and D. Mihalache, “P-poiarized nonlinear surface polaritons in layered structures,” Z. Phys. B. 47, 167 (1982). [CrossRef]  

11. A. A. Maradudin, “Nonlinear surface electromagnetic waves,” in Proc. 2nd Int. School Condensed Matter Phys., Varna, Bulgaria, Singapore: World Scientific (1983).

12. D. Mihalache, R. G. Nazmitdinov, and V. K. Fedyanin, “P-polarized nonlinear surface waves in symmetric layered structures.” Phys. Scripta. 29, 269 (1984). [CrossRef]  

13. A. E. Kaplan, “Theory of hysteresis reflection and refraction of light by a boundary of a nonlinear medium,” Sov. Phys.-JETP. 45, 896 (1977).

14. S. She and S. Zhang, “Analysis of nonlinear TE waves in a periodic refractive index waveguide with nonlinear cladding,” Opt. Commmun. 161, 141 (1999). [CrossRef]  

15. Y. D. Wu, M. H. Chen, and H. J. Tasi, “A General Method for Analyzing the Multilayer Optical Waveguide with Nonlinear Cladding and Substrate”, SPIE Design, Fabrication, and Characterization of Photonic Dervice II , 4594. 323 (2001).

16. Y. D. Wu and M. H. Chen, “Analyzing multilayer optical waveguides with nonlinear cladding and substrates,” J. Opt. Soc. Am. B. 19, 1737, (2002). [CrossRef]  

17. Y. D. Wu and M. H. Chen, “The fundamental theory of the symmetric three layer nonlinear optical waveguide structures and the numerical simulation,” J. Nat. Kao. Uni. of App. Sci. , 32. 133 (2002).

18. M. H. Chen, Y. D. Wu, and R. Z. Tasy, “Analyses of antisymmetric modes of three-layer nonlinear optical waveguide,” J. Nat. Kao. Uni. of App. Sci. , 34. 1 (2005)

19. H. Murata, M. Izutsu, and T. Sueta, “Optical bistability and all-optical switching in novel waveguide junctions with localized optical nonlinearity,” J. Lightwave Technol. 16, 833 (1998). [CrossRef]  

20. Y. D. Wu, “Analyzing multilayer optical waveguides with a localized arbitrary nonlinear guiding film,” IEEE J. Quantum Electron. 40, 529 (2004). [CrossRef]  

21. Y. D. Wu and D. H. Cai, “Analytical and numerical analyses of TE-polarized waves in the planar optical waveguides with the nonlinear guiding film,” J. Eng. Tech. and Edu. 1 , 19 (2004).

22. Yi-Fan Li and Keigo Iizuka, ”Unified Nonlinear Waveguide Dispersion Equations withtour Spurious Roots,” IEEE J. Quantum. Electron. 31, 791 (1995). [CrossRef]  

23. M. Cada, R. C. Gauthior, B. A. Paton, and J. Chrostowski, “Nonlinear guided waves coupled nonlinearly in a planar GaAs/GaAlAs multiple-quantum-well structure,” Appl. Phys. Lett. 49, 755 (1986). [CrossRef]  

24. T. H. Wood, “Multiple-quantum-well (MQW) waveguided modulator,” J. Lightwave Technol. 6, 743 (1988). [CrossRef]  

25. G. I. Stegeman, E. M. Wright, N. Finlayson, R. Zanoni, and C. T. Seaton, “Third order nonlinear integrated optics,” J. Lightwave Technol. 6, 953 (1988). [CrossRef]  

26. S. R. Cvetkovic and A. P. Zhao, “Finite-element formalism for linear and nonlinear guided waves in multiple-quantum-well waveguides,” J. Opt. Soc. Amer. B. 10, 1401 (1993). [CrossRef]  

27. S. Selleri and M. Zobol, “Stability analysis of nonlinear TE polarized waves in multiple-quantum-well waveguides,” IEEE J. Quantum Electron. 31, 1785 (1995). [CrossRef]  

28. C. J. Hamiltoin, J. H. Marsh, D. C. Hutchings, J. S. Aitchison, G. T. Kennedy, and W. Sibbett, “Localized Kerr-type nonlinearities in GaAs/AlGaAs multiple quantum well structure at 1.55μm,” Appl. Phys. Lett. 68, 3078 (1996). [CrossRef]  

29. C. Rigo, L. Gastaldi, D. Campi, L Faustini, C. Coriasso, C. Cacciatore, and D. Sholdani, “Multiple quantum well compressive strained heterostructures for low driving power all-optical waveguide switches,” J. Crystal. Growth. 188, 317 (1998). [CrossRef]  

30. Y. D. Wu, M. H. Chen, and C. H. Chu, “All-optical logic device using bent nonlinear tapered Y-junction waveguide structure,” Fiber and Integrated Optics. 20, 517 (2001).

31. Y. D. Wu, “Nonlinear all-optical switching device by using the spatial soliton collision,” Fiber and Integrated Optics. 23, 387 (2004). [CrossRef]  

32. Y. D. Wu, “New all-optical wavelength auto-router based on spatial solitons,” Opt. Express. 12, 4172 (2004). http://www.opticsexpress.org/abstract.cfm?URI=OPEX-12-18-4172 [CrossRef]   [PubMed]  

33. Y. D. Wu, Y. F. Laio, M. H. Chen, and K. H. Chiang, “Nonlinear all-optical phase and power-controlled switch by using the spatial solitons interaction,” SPIE. Bellingham. WA. 5646, 334 (2005).

34. Y. D. Wu, Y. F. Laio, M. H. Chen, and K. H. Chiang, “A new all-optical phase-controlled routing switch,” SPIE. Bellingham. WA. 5646, 345 (2005).

35. Y. D. Wu, “1×N all-optical switching device by using the phase modulation of spatial solitons,” Applied. Optics. 44,4144(2005). [CrossRef]   [PubMed]  

36. Y. D. Wu, “All-optical logic gates by using multibranch waveguide structure with localized optical nonlinearity,” IEEE J. Sel. Top. Quantum. Electron. 11, 307 (2005). [CrossRef]  

37. T. Yabu, M. Geshiro, T. Kitamura, K. Nishida, and S. Sawa, “All-optical logic gates containing a two-mode nonlinear waveguide,” IEEE J. Quantum. Electron. 38, 37 (2002). [CrossRef]  

38. F. Garzia and M. Bertolotti, “All-optical security coded key,” Opt. Quantum. Electron. 33, 527, (2001). [CrossRef]  

39. Y. H. Pramono and Endarko, “Nonlinear waveguides for optical logic and computation,” J. Nonlinear Opt. Phys. Mater. 10, 209 (2001). [CrossRef]  

40. W. K. Burns and A. F. Milton, “Mode conversion in planar dielectric separating waveguide,” IEEE J. Quantum. Electron. 11, 32 (1975). [CrossRef]  

41. D. Marcuse, “Radiation losses of tapered dielectric slab wave-guides,” Bell Syst; Tech. J. , 49, 273, (1970). [PubMed]  

42. C. T. Seaton, J. D. Valera, R. L Shoemaker, G. I. Stegeman, J. T. Chilwell, and D. Smith, “Calculations of nonlinear TE waves guided by thin dielectric films bounded by nonlinear media,” IEEE J. Quantum. Electron. 21, 774, (1985). [CrossRef]  

43. C. T. Seaton, X. Mai, G. I. Stegeman, and N. G. Winful, “Nonlinear guided wave applications,” Opt. Eng. , 24, 593 (1985).

44. H. Vach, G. I. Stegeman, C. T. Seaton, and I. C. Khoo, “Experimental observation of nonlinear guided waves,” Opt. Lett. 9, 238 (1984). [CrossRef]   [PubMed]  

45. H. F. Chou, C. F. Lin, and G. C. Wang, “An Interative Finite Difference Beam Propagation Method for Modeling Second-Order Nonlinear Effects in Optical Waveguides,” J. Lightwave. Technol. 16, 1686 (1998). [CrossRef]  

Cited By

Optica participates in Crossref's Cited-By Linking service. Citing articles from Optica Publishing Group journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (13)

Fig. 1.
Fig. 1. The structure of multilayer optical waveguides with all nonlinear guiding films.
Fig. 2.
Fig. 2. Diagram of the computation steps (9)–(11)
Fig. 3.
Fig. 3. (a)Dispersion curve of the three-layer optical waveguide structure with the nonlinear central guiding film. (b)The electric field distributions with respect to points A-D as shown in (a).
Fig. 4.
Fig. 4. (a)Dispersion curve of the five-layer optical waveguide structure with the nonlinear central guiding film. (b)The electric field distributions with respect to points A-D as shown in (a).
Fig. 5.
Fig. 5. (a)Dispersion curve of the seven-layer optical waveguide structure with the nonlinear central guiding film. (b)The electric field distributions with respect to points A-D as shown in (a).
Fig. 6.
Fig. 6. The multibranch optical waveguide structure with all nonlinear guiding branches (N denoted the nonlinear medium).
Fig. 7.
Fig. 7. The three-branch optical waveguide structure with all nonlinear guiding branches (N denoted the nonlinear medium).
Fig. 8.
Fig. 8. For the low input power density case, electric-field distributions of the three-branch optical waveguide structure with all nonlinear guiding branches at positions (a)Z1 (df = 3μm , β = 1.5654), (b)Z2 (df = 6μm, β = 1.5654), (c)Z3 (df = 3μm , dI = 5μm , β = 1.5655), (d)Z4 (df = 3μm , dI = 7μm, β = 1.56545).
Fig. 9.
Fig. 9. For the high input power density case, electric-field distributions of the three-branch optical waveguide structure with all nonlinear guiding branches at positions (a)Z1 (df = 3μm , β = 1.56925), (b)Z2 (df = 6μm, β = 1.56925), (c)Z3 (df = 3μm , dI = 5μm, β = 1.5690), (d)Z4 (df = 3μm, dI = 7μm, β = 1.5693).
Fig. 10.
Fig. 10. The typical evolution of a wave propagating along a three-branch optical waveguide structure with all nonlinear guiding branches at the low input power density.
Fig. 11.
Fig. 11. The typical evolution of a wave propagating along a three-branch optical waveguide structure with all nonlinear guiding branches at the high input power density.
Fig. 12.
Fig. 12. The relevant curves shown in Figs. 6 and 8 on the same graph (a) at position Z1, (b) at position Z2, (c) at position Z3, (d) at position Z4. (┄:the predicted results;―: the numerical simulation results).
Fig. 13.
Fig. 13. The relevant curves shown in Figs. 7 and 9 on the same graph (a) at position Z1, (b) at position Z2, (c) at position Z3, (d) at position Z4. (┄:the predicted results;―: the numerical simulation results).

Equations (49)

Equations on this page are rendered with MathJax. Learn more.

2 E yi = n i 2 c 2 2 E yi t 2 , i = 1,2 , , m
E yi x z t = ε i ( x ) exp [ j ( ωt βk 0 z ) ]
n i 2 = n 0 i 2 + α i ε i ( x ) 2 , i = 2,4 , , m 1
ε 1 ( x ) = E s exp ( p 1 x ) in the substrate
ε i ( x ) = E I ( i 2 ) exp { p i [ x ( i 1 2 ) d ( i 3 2 ) w ] } + E I ( i 1 ) { exp p i [ x ( i 1 2 ) d ( i 1 2 ) w ] }
i = 3,5 , , m 2 in the interaction layers
ε i ( x ) = b i cn { A i [ x ( i 2 1 ) ( d + w ) + x 0 i ] l i }
i = 2,4 , , m 1 in the guiding film , for β < n i
ε i ( x ) = b i ¯ cn { A i ¯ [ x ( i 2 1 ) ( d + w ) + x ̅ 0 i ] l i ¯ }
i = 2,4 , , m 1 in the guiding film , for β > n i
ε m ( x ) = E c exp { p m [ x ( m 1 2 ) d ( m 3 2 ) w ] } in the cladding
p i = k 0 β 2 n i 2 ,
b i 2 = q i 4 + 2 α i k 0 2 K i q i 2 α i k 0 2 ,
A i = [ ( a i 2 + b i 2 ) ( α i k 0 2 2 ) ] 1 2 ,
l i = b i 2 ( a i 2 + b i 2 ) ,
b ̅ i 2 = Q i 4 + 2 α i k 0 2 K i + Q i 2 α i k 0 2 ,
A ̅ i = [ ( a ̅ i 2 + b ̅ i 2 ) ( α i k 0 2 2 ) ] 1 2 ,
l ̅ i = b ̅ i 2 ( a ̅ i 2 + b ̅ i 2 ) ,
[ cn ( A m 1 d ) Δ m 2 + + sn ( A m 1 d ) dn ( A m 1 d ) p m 2 Δ m 2 A m 1 ] [ 1 l m 1 ( 1 Δ m 2 + 2 b m 1 2 ) sn 2 ( A m 1 d ) ] A m 1 = { Δ m 2 + [ 1 l m 1 ( 1 Δ m 2 + 2 b m 1 2 ) sn ( A m 1 d ) dn ( A m 1 d ) ] Δ m 2 + l m 1 ( 1 Δ m 2 + 2 b m 1 2 ) sn ( A m 1 d ) cn 2 ( A m 1 d ) dn ( A m 1 d ) + p m 2 Δ m 2 A m 1 [ cn ( A m 1 d ) dn 2 ( A m 1 d ) l m 1 Δ m 2 + 2 b m 1 4 sn 2 ( A m 1 d ) cn ( A m 1 d ) ] } [ 1 l m 1 ( 1 Δ m 2 + 2 b m 1 4 ) sn 2 ( A m 1 d ) ] 2 p m ,
where Δ m 2 + = E I ( m 4 ) exp ( p m 2 w ) + E I ( m 3 ) ,
Δ m 2 = E I ( m 4 ) exp ( p m 2 w ) E I ( m 3 ) .
E c P 3 A 2 b 2 = { E s b 2 [ 1 l 2 ( 1 E s 2 b 2 2 ) ] sn ( A 2 d ) dn ( A 2 d ) l 2 E s b 2 ( 1 E s 2 b 2 2 ) sn ( A 2 d ) cn 2 ( A 2 d ) dn ( A 2 d ) E s p 1 b 2 A 2 [ cn ( A 2 d ) dn 2 ( A 2 d ) l 2 E s 2 b 2 2 sn 2 ( A 2 d ) cn ( A 2 d ) ] } [ E s E c cn ( A 2 d ) + E s p 1 E c A 2 sn ( A 2 d ) dn ( A 2 d ) ] 2 ,
for m = 5 ,
[ Δ 3 + cn ( A 4 d ) p 3 Δ 3 A 4 sn ( A 4 d ) dn ( A 4 d ) ] [ 1 l 4 ( 1 Δ 3 + 2 b 4 2 ) sn 2 ( A 4 d ) ] A 4 = { Δ 3 + [ 1 l 4 ( 1 Δ 3 + 2 b 4 2 ) ] sn ( A 4 d ) dn ( A 4 d ) Δ 3 + l 4 ( 1 Δ 3 + 2 b 4 2 ) sn ( A 4 d ) dn ( A 4 d ) cn 2 ( A 4 d ) } + p 3 Δ 3 A 4 cn ( A 4 d ) [ dn 2 ( A 4 d ) l 4 Δ 3 + 2 b 4 2 sn 2 ( A 4 d ) ] [ 1 l 4 ( 1 Δ 3 + 2 b 4 2 ) sn 2 ( A 4 d ) ] 2 p 5 ,
where Δ 3 + = E I 1 exp ( p 3 w ) + E I 2 ,
Δ 3 = E I 1 exp ( p 3 w ) + E I 2 ,
a i 2 = q i 4 + 2 α i k 0 2 K i + q i 2 α i k 0 2 ,
a ̅ i 2 = q i 4 + 2 α i k 0 2 K i Q i 2 α i k 0 2 ,
A i = [ ( a i 2 + b i 2 ) ( α i k 0 2 2 ) ] 1 2 ,
A ̅ i = [ ( a ̅ i 2 + b ̅ i 2 ) ( α i k 0 2 2 ) ] 1 2 ,
q i 2 = k 0 ( n i 2 β 2 ) , for β < n i ( n i = 2,4 , , m 1 ) ,
Q i 2 = k 0 ( β 2 n i 2 ) , for β > n i ( n i = 2,4 , , m 1 ) ,
E I 1 = 1 2 { [ E s cn ( A 2 d ) + p 1 E s A 2 sn ( A 2 d ) dn ( A 2 d ) ] [ 1 l 2 sn 2 ( A 2 d ) ( 1 E s 2 b 2 2 ) ] }
+ A 2 { E s sn ( A 2 d ) dn ( A 2 d ) { [ 1 l 2 ( 1 E s 2 b 2 2 ) ] l 2 ( 1 E s 2 b 2 2 ) cn 2 ( A 2 d ) } p 1 E s A 2 cn ( A 2 d ) [ dn 2 ( A 2 d ) l 2 E s 2 b 2 2 sn 2 ( A 2 d ) ] p 3 [ 1 l 2 sn 2 ( A 2 d ) ( 1 E s 2 b 2 2 ) ] 2 } ,
E Ii = 1 2 { [ Δ i 2 + cn ( A i + 1 d ) + p i 2 Δ i 2 A i + 1 ] sn ( A i + 1 ) dn ( A i + 1 d ) [ 1 l i + 1 ( 1 Δ i 2 + 2 b i + 1 2 ) sn 2 ( A i + 1 d ) ] + A i + 1 { Δ i 2 + [ 1 l i + 1 ( 1 Δ i 2 + 2 b i + 1 2 ) ] [ 1 l i + 1 cn 2 ( A i + 1 ) ] sn ( A i + 1 d ) dn ( A i + 1 d ) Δ i 2 + l i + 1 ( 1 Δ i 2 + 2 b i + 1 4 ) sn ( A i + 1 d ) cn 2 ( A i + 1 d ) dn ( A i + 1 d ) Δ i 2 p i 2 A i + 1 cn ( A i + 1 d ) [ dn 2 ( A i + 1 d ) l i + 1 Δ i 2 + 2 b i + 1 2 sn 2 ( A i + 1 d ) ] } [ 1 l i + 1 sn 2 ( A i + 1 d ) ( 1 Δ i 2 + 2 b i + 1 4 ) ] 2 p i } , i = 3,5 , m 2 ,
where Δ i 2 + = E Ii 2 + E Ii 1 exp ( p i 2 w ) ,
Δ i 2 = E Ii 2 E Ii 1 exp ( p i 2 w ) .
For i = 4,6 , m 3 ,
x 0 i = 1 A i cn 1 ( E I ( i 3 ) exp ( p ( i 1 ) w ) + E I ( i 2 ) b i ) ,
x ̅ 0 i = 1 A i ¯ cn 1 ( E I ( i 3 ) exp ( p ( i 1 ) w ) + E I ( i 2 ) b i ¯ ) ,
K i = k 0 2 E I ( i 1 ) 2 ( n i 2 n i + 1 2 + α i E I ( i 1 ) 2 2 ) + k 0 2 E Ii 2 exp ( 2 p ( i + 1 ) w ) [ n i 2 n i + 1 2 + α i E Ii 2 2 exp ( 2 p ( i + 1 ) w ) ]
+ 2 E I ( i 1 ) E Ii k 0 2 exp ( p ( i + 1 ) w ) [ n i 2 2 β 2 + n i + 1 2 + 3 2 α i E I ( i 1 ) E Ii exp ( p ( i + 1 ) w ) ]
+ 2 α i E I ( i 1 ) E Ii k 0 2 exp ( p ( i + 1 ) w ) [ E I ( i 1 ) 2 + E Ii 2 exp ( 2 p ( i + 1 ) w ) ] .
x 02 = 1 A 2 cn 1 ( E 0 b 2 ) ,
x 0 m 1 = 1 A m 1 cn 1 ( E 0 b m 1 ) d ,
x ̅ 02 = 1 A 2 ¯ cn 1 ( E 0 b ̅ 2 ) ,
x ̅ 0 m 1 = 1 A ̅ m 1 cn 1 ( E 0 b ̅ m 1 ) d ,
K 2 = k 0 2 E 0 2 ( n 2 2 n 1 2 + α 2 E 0 2 2 ) ,
K m 1 = k 0 2 E m 2 ( n m 1 2 n m 2 + α ( m 1 ) E m 2 2 ) .
Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All rights reserved, including rights for text and data mining and training of artificial technologies or similar technologies.