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  • TA的每日心情
    郁闷
    2015-6-6 15:06
  • 签到天数: 5 天

    [LV.2]偶尔看看I

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    1#
    发表于 2015-6-2 12:57 |只看该作者 |倒序浏览
    |招呼Ta 关注Ta |邮箱已经成功绑定
    1. lamda = 1.55 10^-6;1 }. t/ T8 Z9 m0 {
    2. k0 = 2*Pi/lamda;6 V. V0 t' _$ h* \4 ?5 Q9 C  J7 y8 j* Y
    3. n1 = 1.4677;(*纤芯折射率*): o1 H! @) o+ e$ R4 e+ k8 o' u6 b+ D! z* M
    4. n2 = 1.4628;(*包层折射率*); V0 e) D3 B7 F0 O2 f$ J
    5. n3 = 0.469 + 9.32*I;(*银折射率*)
      . o\" G  B5 i2 M6 F4 A2 {/ V
    6. a1 = 4.1 10^-6;(*纤芯半径*)
      \" U0 q2 _' T  Z- K
    7. a2 = 62.5 10^-6;(*包层半径*)* V; p8 R6 z2 f- S
    8. d = 40 10^-9;(*金属厚度*)
      . U$ D: ^& ]. t7 m& S
    9. a3 = a2 + d;' O3 C9 v: a# i6 P; X; U- }
    10. mu = Pi*4 10^-7;(*真空磁导率*)
      8 }5 Q) }, J9 h  r  K1 c& F* O; m/ f6 x
    11. epsi0 = 8.85 10^-12;(*介电常数*); s8 p$ p/ h4 @
    12. # r. b8 ?) [3 U9 u
    13. n4 = 1.330;: q' j1 Q8 ]3 D

    14. 9 M) [9 L$ b8 P) a1 ~
    15. neffcl = neffclre + neffclim*I;5 ~+ _4 e# ^& n0 ~

    16. 8 g* A$ c; \3 V/ g: p
    17. betacl = k0*neffcl;
      . \' {* h+ @9 r7 x\" D) A7 k2 h
    18. omega = 2*Pi*299792458/lamda;
      + }, c: K( T% l; f( \, V! Y
    19. 7 G9 W. I( o0 c) A/ ^* a: P
    20. epsi1 = n1^2*epsi0;
      & g, o5 k1 A. B2 t+ N
    21. epsi2 = n2^2*epsi0;' R  X0 b! B3 o% ]9 T
    22. epsi3 = n3^2*epsi0;' |  F+ `7 n! D3 @
    23. epsi4 = n4^2*epsi0;
      ) X0 E0 G* h. F: K  q
    24. & }' K\" `: I) {% M- b0 Y1 F( {
    25. u1 = k0*Sqrt[neffcl^2 - n1^2];7 q\" q) o0 I; R( h
    26. u2 = k0*Sqrt[neffcl^2 - n2^2];
      & f: q& I5 B* E
    27. u3 = k0*Sqrt[neffcl^2 - n3^2];) \) i2 X. D( L( I, p0 l1 J! Y& L
    28. w4 = k0*Sqrt[neffcl^2 - n4^2];
      ! ?8 G6 i: G! ]4 o( b2 ?* m) P

    29. + W) V/ R! J6 d  h
    30. Iua111 = BesselI[1, u1*a1];5 e/ v- b: s9 H& U
    31. Iua121 = BesselI[1, u2*a1];/ Y+ `& j+ f8 a: W4 ?% I
    32. Iua122 = BesselI[1, u2*a2];
      5 g: z\" S* {! p
    33. Iua132 = BesselI[1, u3*a2];
      ! Z2 p. d: N7 v$ f+ `
    34. Iua133 = BesselI[1, u3*a3];
      2 C9 `; t' n  M. m/ h
    35. IIua111 = (BesselI[0, u1*a1] + BesselI [2, u1*a1])/2;
      9 C+ z6 @. C. r  I  m. d+ K8 {* d: A$ I. v
    36. IIua121 = (BesselI [0, u2*a1] + BesselI [2, u2*a1])/2;3 N  c9 e: e+ Z6 G& [/ m
    37. IIua122 = (BesselI[0, u2*a2] + BesselI[2, u2*a2])/2;
      1 y$ z$ I1 `% ~
    38. IIua132 = (BesselI[0, u3*a2] + BesselI[2, u3*a2])/2;
      # A! G2 m7 _$ {
    39. IIua133 = (BesselI[0, u3*a3] + BesselI[2, u3*a3])/2;* c4 K# \8 c: T6 @: q' }
    40. / C4 m1 H) Z1 G1 w/ \
    41. Kua121 = BesselK [1, u2*a1];% i7 p/ e8 x9 Q! e, C, E7 q# v
    42. Kua122 = BesselK [1, u2*a2];
      ( s# t: u) Q: A; u3 |
    43. Kua132 = BesselK [1, u3*a2];8 F1 o8 B5 q0 C1 s; h
    44. Kua133 = BesselK [1, u3*a3];2 H7 ~) Z- `' h* m
    45. Kwa143 = BesselK [1, w4*a3];
      3 R8 B8 V  J* t' z, w
    46. KKua121 = -(BesselK [0, u2*a1] + BesselK [2, u2*a1])/2;
      , W/ D( b: q) r$ k0 H
    47. KKua122 = -(BesselK [0, u2*a2] + BesselK [2, u2*a2])/2;5 I2 M( Y& t6 n9 u7 ]) u% f
    48. KKua132 = -(BesselK [0, u3*a2] + BesselK [2, u3*a2])/2;# E\" _  }7 {1 ]+ b% @
    49. KKua133 = -(BesselK [0, u3*a3] + BesselK [2, u3*a3])/2;
      1 H, {/ S  `  f; z% A
    50. KKwa143 = -(BesselK [0, w4*a3] + BesselK [2, w4*a3])/2;) a- p0 I' {$ d4 d: t' I4 T
    51. 5 g9 t: g7 [$ _. ^2 A: D$ [
    52. H1 = (betacl*Kwa143*
      3 D5 D% }$ v# a3 C
    53.       Kua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3)*(u3/u2*IIua132*7 M5 Q! U5 s, i5 W+ a; [
    54.        Kua122 - u3^2/u2^2*Iua132*KKua122) - (betacl*Kwa143*2 x1 \5 p\" l9 y0 a
    55.       Iua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3)*(u3/u2*KKua132*$ `6 Q  |+ ]# B3 D2 B: ~' B9 T1 H
    56.        Kua122 - u3^2/u2^2*Kua132*KKua122) + (betacl*Iua132*
      $ h. D# U3 ~2 r, @
    57.       Kua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(w4/u3*KKwa143*! e2 T; v  \+ Q3 _0 Q
    58.        Kua133 - w4^2*epsi3/u3^2/epsi4*Kwa143*KKua133) - (betacl*. n/ m1 R* y  W& _$ N
    59.       Kua132*Kua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(w4/u3*KKwa143*
      5 M# i9 {  }+ K3 E1 Y
    60.        Iua133 - w4^2*epsi3/u3^2/epsi4*Kwa143*IIua133);8 f, t7 ^! B8 H; q' S2 x
    61. * W) s+ C0 C# _8 t\" B0 c, H1 d
    62. H2 = (betacl*Kwa143** d0 a3 |0 r$ A
    63.       Kua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3)*(u3/u2*IIua132*& C: t: k* @6 N) C5 i# S
    64.        Iua122 - u3^2/u2^2*Iua132*IIua122) - (betacl*Kwa143*
      & u& u4 g- S# }5 I& H0 n2 m
    65.       Iua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3)*(u3/u2*KKua132*
      6 M/ C\" j  {2 p, }) f
    66.        Iua122 - u3^2/u2^2*Kua132*IIua122) + (betacl*Iua132*) A; D\" p. O3 U6 J+ v
    67.       Iua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(w4/u3*KKwa143*
      # E! H7 L/ }/ I2 U
    68.        Kua133 - w4^2*epsi3/u3^2/epsi4*Kwa143*KKua133) - (betacl*
      4 }+ N/ _. S5 e8 Y' y' m1 u
    69.       Kua132*Iua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(w4/u3*KKwa143*0 i$ o2 g4 I- Z: ~\" @; q
    70.        Iua133 - w4^2*epsi3/u3^2/epsi4*Kwa143*IIua133);; v$ }8 v) f1 d, `) e& p5 ?
    71. # B3 e% I: J0 _\" |: L& H3 K9 @5 b
    72. H3 = (betacl*Iua132*Kua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(betacl*: Q( `2 L3 I! X' b5 v: n/ z1 J1 S* X
    73.       Kwa143*Kua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3) - (betacl*
      & D1 o) a# G8 l5 O2 C, Z
    74.       Kua132*Kua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(betacl*Kwa143*( ~) ^# y% l) Z$ i5 X
    75.       Iua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3) + (u3/u2*IIua132*
      ' \, g) f9 H- z( q( o
    76.        Kua122 - 0 E, [0 e+ X9 ?! |) Q1 W
    77.       u3^2*epsi2/u2^2/epsi3*Iua132*KKua122)*(w4/u3*KKwa143*Kua133 -
      . b5 R\" F/ |+ ~- m3 M8 ?
    78.       w4^2*epsi3/u3^2/epsi4*Kwa143*KKua133) - (u3/u2*KKua132*Kua122 -
      ( R: V1 V! Q6 m9 l& D
    79.       u3^2*epsi2/u2^2/epsi3*Kua132*KKua122)*(w4/u3*KKwa143*Iua133 - 1 A  x) B$ F- X& ^3 d5 A0 n% ?; I
    80.       w4^2*epsi3/u3^2/epsi4*Kwa143*IIua133);
      ) H3 l+ d3 q- W# z
    81. \" \2 v: A4 Z3 M2 [% J) O\" i9 |8 R
    82. H4 = (betacl*Iua132*Iua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(betacl*/ t. S% h, [8 z( A
    83.       Kwa143*Kua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3) - (betacl*
      ; R8 \6 |\" F4 ]6 H7 `' c$ k& J* i
    84.       Kua132*Iua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(betacl*Kwa143*3 H3 Q5 i6 b6 O; H8 C
    85.       Iua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3) + (u3/u2*IIua132*
      & Y& A* q$ e6 w8 M$ t2 I' |1 J5 p
    86.        Iua122 -
      0 p: g4 z8 G1 k+ c5 x+ d. L
    87.       u3^2*epsi2/u2^2/epsi3*Iua132*IIua122)*(w4/u3*KKwa143*Kua133 -
      2 Y0 {4 T! q9 Q
    88.       w4^2*epsi3/u3^2/epsi4*Kwa143*KKua133) - (u3/u2*KKua132*Iua122 -
      & f5 d, v- t$ z8 v
    89.       u3^2*epsi2/u2^2/epsi3*Kua132*IIua122)*(w4/u3*KKwa143*Iua133 - . S; `2 {# A# V* Z
    90.       w4^2*epsi3/u3^2/epsi4*Kwa143*IIua133);: u! C: _8 i2 Z: T' ^7 L! y
    91. 8 h6 |# z6 w& V; X; o- w0 S  b: o, |
    92. M1 = (betacl*Iua132*Kua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(betacl*7 \% |9 D; l) d2 F3 Y' K1 a
    93.       Kwa143*Kua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3) - (betacl*Kua132*
      : Q: R/ o/ b5 M' e. c$ f5 J! W
    94.       Kua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(betacl*Kwa143*
      5 T* M6 `2 T1 T3 n# ^. P! d, r  T
    95.       Iua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3) + (u3/u2*IIua132*Kua122 -( ?) x2 A4 f& F( r( ]
    96.        u3^2/u2^2*Iua132*KKua122)*(w4/u3*KKwa143*Kua133 - 3 H) t2 ^5 E2 _  e% l
    97.       w4^2/u3^2*Kwa143*KKua133) - (u3/u2*KKua132*Kua122 - ' k2 U- d: `+ B! V
    98.       u3^2/u2^2*Kua132*KKua122)*(w4/u3*KKwa143*Iua133 - 3 T9 o* @: u( h- `
    99.       w4^2/u3^2*Kwa143*IIua133);9 |# y& R. j, ^
    100. * d$ f* t+ a/ u4 t
    101. M2 = (betacl*Iua132*Iua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(betacl*
      9 f) l) A& V0 O
    102.       Kwa143*Kua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3) - (betacl*Kua132*8 S. g' v1 R* C$ q% _
    103.       Iua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(betacl*Kwa143*% `4 l1 o8 o8 h+ x  K8 b
    104.       Iua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3) + (u3/u2*IIua132*Iua122 -
      9 z6 G7 v8 _  }6 Y4 q- {, ~+ y! t' f
    105.        u3^2/u2^2*Iua132*IIua122)*(w4/u3*KKwa143*Kua133 - ) Z% O5 G/ m\" U7 p& W7 @- O
    106.       w4^2/u3^2*Kwa143*KKua133) - (u3/u2*KKua132*Iua122 - : y5 ]$ [: b. b$ ^% B4 K& J
    107.       u3^2/u2^2*Kua132*IIua122)*(w4/u3*KKwa143*Iua133 -
      ! |& C( Q2 P! U) ?6 _7 [  y
    108.       w4^2/u3^2*Kwa143*IIua133);! P: b+ T% h0 }* O: l. I, t) f
    109. ' S  x3 _) X8 D: ~! z3 i. N1 M
    110. M3 = (betacl*Kwa143*
      9 G$ g7 v0 o8 o+ F1 |# g
    111.       Kua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3)*(u3/u2*IIua132*Kua122 - . B1 p( K& g( }
    112.       u3^2*epsi2/u2^2/epsi3*Iua132*KKua122) - (betacl*Kwa143*+ B! n( z9 P! \
    113.       Iua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3)*(u3/u2*KKua132*Kua122 -
      / r6 L$ q' n( q* k6 L# I
    114.       u3^2*epsi2/u2^2/epsi3*Kua132*KKua122) + (betacl*Iua132*
      ) A! i3 ~! V3 s' ]% }\" A% V
    115.       Kua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(w4/u3*KKwa143*Kua133 -
      4 e4 S3 E  p  A5 a6 d+ v, {
    116.       w4^2/u3^2*Kwa143*KKua133) - (betacl*Kua132*& i5 U; n& n; h/ W/ A/ f\" t
    117.       Kua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(w4/u3*KKwa143*Iua133 -
      : p/ G- p! T0 R/ S$ b
    118.       w4^2/u3^2*Kwa143*IIua133);7 M; t0 j; \5 F5 [0 r3 S: u$ D
    119. # M( X7 k( M8 m9 I% C4 p1 W
    120. M4 = (betacl*Kwa143*
      \" v/ u, D% B0 r1 {' H
    121.       Kua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3)*(u3/u2*IIua132*Iua122 -
      5 S: g- _; \, S/ T/ ~
    122.       u3^2*epsi2/u2^2/epsi3*Iua132*IIua122) - (betacl*Kwa143*\" c. q% j2 A2 @
    123.       Iua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3)*(u3/u2*KKua132*Iua122 -
      3 i/ ]' W6 q2 {3 g\" V; g# {) X
    124.       u3^2*epsi2/u2^2/epsi3*Kua132*IIua122) + (betacl*Iua132*, }4 f8 R. g! n( M. Q& b
    125.       Kua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(w4/u3*KKwa143*Kua133 -
      3 r- S! H. V4 Y0 @1 ]- k\" B
    126.       w4^2/u3^2*Kwa143*KKua133) - (betacl*Kua132*
      3 X2 s* q+ C; I( z$ l
    127.       Iua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(w4/u3*KKwa143*Iua133 - % W# `- b. e* C
    128.       w4^2/u3^2*Kwa143*IIua133);
      & ^+ t\" m8 C9 N3 {9 D
    129. 7 A/ O! }6 C\" ?7 y7 }9 b5 }# T
    130. R1 = u2^2/u1^2*Iua121*IIua111 - u2/u1*IIua121*Iua111;
      7 t9 Z3 [: c, Q3 ~( K0 U) Q
    131. T1 = u2^2/u1^2*Kua121*IIua111 - u2/u1*KKua121*Iua111;* U5 m+ S7 e7 Z, C. |4 C. ?
    132. U1 = betacl*Iua121*Iua111*(u2^2/u1^2 - 1)/omega/epsi2/u1/a1;
      \" o9 Y5 g* o) N  r4 ?  M2 O1 Y
    133. V1 = betacl*Kua121*Iua111*(u2^2/u1^2 - 1)/omega/epsi2/u1/a1;/ r+ Z7 U6 I, q+ G0 [5 b' U

    134. . h, u. T+ @; |# h
    135. R2 = u2^2/u1^2*epsi1/epsi2*Iua121*IIua111 - u2/u1*IIua121*Iua111;4 L0 @; Y* v; r' g7 ?
    136. T2 = u2^2/u1^2*epsi1/epsi2*Kua121*IIua111 - u2/u1*KKua121*Iua111;: T4 X0 z% |# }, K
    137. U2 = betacl*Iua121*Iua111*(u2^2/u1^2 - 1)/omega/mu/u1/a1;
      $ [# D5 x2 l: X/ a: F
    138. V2 = betacl*Kua121*Iua111*(u2^2/u1^2 - 1)/omega/mu/u1/a1;# k. Y0 z* ^/ N! L' _: W
    139. 6 o$ k  Z) w9 j0 L2 j. V# Z. g1 |
    140. xicl1 = (-R1*H1 + T1*H2 + U1*H3 - V1*H4)/(R1*M1 - T1*M2 - U1*M3 +
        W\" v0 H6 M6 p/ t- s7 T0 F
    141.      V1*M4);$ Y- o- Q, B; n3 l$ u
    142. xicl2 = (-R2*H3 + T2*H4 + U2*H1 - V2*H2)/(R2*M3 - T2*M4 - U2*M1 +
      ' m) S9 z* u\" T! U# C
    143.      V2*M2);
      ! x; M1 O$ W, w7 i  o& S
    144. : |7 S0 W- A5 E7 a% S( \& G
    145. x = xicl1 - xicl2;
      4 x8 m\" M/ p0 I9 E: f\" h5 u. Z
    146. x1 = Re[x];
      : O- `7 R- O5 i+ V
    147. x2 = Im[x];$ b! U% k4 G3 {* ~
    148. 8 G: k7 Q4 S' U! b( p' l! w
    149. FindRoot[{x1,x2},{{neffclre,1.333},{neffclim,0.00001}}];
      6 U/ M1 {! L& n  x/ i) U! C- q
    150. ]
      7 r# Z7 G# P% G- |

    151. + l8 n( Y$ S, Z6 v5 _4 ]
    复制代码
    代码如上,结果是{neffclre -> 1.33017, neffclim -> 0.0000172055}& [0 M5 w5 z' t! A/ }3 g" M
    但我把FindRoot[{x1,x2},{{neffclre,1.333},{neffclim,0.00001}}];0 n6 v. {7 U1 ^8 T1 g0 w) B0 Y
    换成7 |  R5 M# r3 v# F8 p+ d. }* \2 h" F
    For[i = 1, i < 133, i++, neffclbase = 1.330 + 0.001*i;# x. n3 C+ Z5 `; K: ]6 f3 d
    FindRoot[{x1, x2}, {{neffclre, neffclbase}, {neffclim, 0.00001}}];
    7 z# V* t6 g+ w  J! x; z- M, k ]# }6 D( N8 f" N3 ^, I8 ?) q' ]
    就会出现2 M& S2 |4 T7 Y) u3 u1 H+ A9 S( L. c2 u
    FindRoot::lstol: 线搜索把步长降低到由 AccuracyGoal 和 PrecisionGoal 指定的容差范围内,但是无法找到 merit 函数的充足的降低. 您可能需要多于 MachinePrecision 位工作精度以满足这些容差.8 |: Q+ w2 O; ~+ m5 D& c9 ~

    ; z* O4 R6 O% v3 d8 A# w请问是怎么回事?% N( H0 r5 q  `9 _: H* |

    ) n4 l" o/ F3 `. X( W: u
    zan
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