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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;
      & X  h7 G* W  }0 [& Z
    2. k0 = 2*Pi/lamda;
      ' |4 L# ^/ V' P7 `' B
    3. n1 = 1.4677;(*纤芯折射率*)8 J  k! G, O* K2 |* z
    4. n2 = 1.4628;(*包层折射率*)
      6 |. f' b4 G) q  I
    5. n3 = 0.469 + 9.32*I;(*银折射率*)& b7 `) Y9 V$ [
    6. a1 = 4.1 10^-6;(*纤芯半径*)9 i6 Y' `: X: l# @
    7. a2 = 62.5 10^-6;(*包层半径*), J4 z  N+ c( v/ A
    8. d = 40 10^-9;(*金属厚度*)8 w. O. h4 K6 c! B5 ^1 C9 k
    9. a3 = a2 + d;\" B+ M4 i* N8 @, \
    10. mu = Pi*4 10^-7;(*真空磁导率*)1 J- R% B\" P2 c0 c) a- @
    11. epsi0 = 8.85 10^-12;(*介电常数*)6 P6 D  \9 J$ ~5 ?
    12. & P3 v! q3 W  I. ^1 M( J* S2 }
    13. n4 = 1.330;
      5 {. U9 A5 T  A  c2 d

    14. ; E& e2 o! [  B) y% m4 i
    15. neffcl = neffclre + neffclim*I;
      - ]/ c. y  q, h\" N

    16. + l3 G5 L/ R$ n7 H1 S4 g# Q/ A
    17. betacl = k0*neffcl;1 Q* x/ h: \5 z! w
    18. omega = 2*Pi*299792458/lamda;
      % j: J( E/ O1 W\" i, T
    19. ! o: V$ n7 o5 {
    20. epsi1 = n1^2*epsi0;  A0 T9 ?' C/ W$ D\" {
    21. epsi2 = n2^2*epsi0;, i0 o6 x4 Q3 _) p
    22. epsi3 = n3^2*epsi0;: U( u( U. z7 r( J7 `
    23. epsi4 = n4^2*epsi0;$ I2 ]& S; M5 I- B

    24. - I4 m. p4 w5 G. F* C1 U7 D0 q2 x& |6 k
    25. u1 = k0*Sqrt[neffcl^2 - n1^2];/ }: e' m\" v' J, T
    26. u2 = k0*Sqrt[neffcl^2 - n2^2];
      3 C$ B3 B3 j6 R& W. F
    27. u3 = k0*Sqrt[neffcl^2 - n3^2];% c, t) R7 y\" H6 L
    28. w4 = k0*Sqrt[neffcl^2 - n4^2];! A) R7 ^1 d4 q

    29. ; G( E3 f7 g. }& e
    30. Iua111 = BesselI[1, u1*a1];# W' `6 z+ c% R! Z* F1 t
    31. Iua121 = BesselI[1, u2*a1];
      7 E: L7 A/ L9 W$ _\" E- S7 d* F
    32. Iua122 = BesselI[1, u2*a2];
      0 Z3 B3 K# X$ v; m+ ^( Y# O8 ?- ^( a\" t' v
    33. Iua132 = BesselI[1, u3*a2];
      % p* ?7 x/ `1 y1 E' H
    34. Iua133 = BesselI[1, u3*a3];
      7 S# \2 V$ `$ p$ g\" R
    35. IIua111 = (BesselI[0, u1*a1] + BesselI [2, u1*a1])/2;
      ' B* v) R, |- |
    36. IIua121 = (BesselI [0, u2*a1] + BesselI [2, u2*a1])/2;- C$ I$ f- i1 B6 c& _4 i
    37. IIua122 = (BesselI[0, u2*a2] + BesselI[2, u2*a2])/2;\" F( w. H9 t9 \9 M. y. I\" @
    38. IIua132 = (BesselI[0, u3*a2] + BesselI[2, u3*a2])/2;- ~5 \' f. ?3 r
    39. IIua133 = (BesselI[0, u3*a3] + BesselI[2, u3*a3])/2;
      # V6 R; k% w- V
    40. 5 X0 U3 ^, {% Q+ V2 J
    41. Kua121 = BesselK [1, u2*a1];
      : ^5 p+ O- v3 ]4 y4 f# Q1 C
    42. Kua122 = BesselK [1, u2*a2];! u\" L$ a8 U( G5 b: a, a; B, y
    43. Kua132 = BesselK [1, u3*a2];: \0 S% V4 d* o  }
    44. Kua133 = BesselK [1, u3*a3];& s! b- ?7 S  d4 M$ _9 q8 L
    45. Kwa143 = BesselK [1, w4*a3];
      7 u% u2 y\" G6 G$ a0 K0 s
    46. KKua121 = -(BesselK [0, u2*a1] + BesselK [2, u2*a1])/2;
      2 R1 |% u4 g6 \; \
    47. KKua122 = -(BesselK [0, u2*a2] + BesselK [2, u2*a2])/2;
      * |( n3 u) F/ W- Y' K
    48. KKua132 = -(BesselK [0, u3*a2] + BesselK [2, u3*a2])/2;4 z+ a( j0 }* e5 ^; q\" @
    49. KKua133 = -(BesselK [0, u3*a3] + BesselK [2, u3*a3])/2;
      # y, x' X) S: O$ O, o, O% A
    50. KKwa143 = -(BesselK [0, w4*a3] + BesselK [2, w4*a3])/2;7 Y+ ]; M: K; v5 x0 J

    51. 0 m4 i6 P: t, u) d9 T% i3 r
    52. H1 = (betacl*Kwa143*
      * F/ k& l# ~0 l) [4 P
    53.       Kua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3)*(u3/u2*IIua132*
      ) w: f3 a! H% |: I
    54.        Kua122 - u3^2/u2^2*Iua132*KKua122) - (betacl*Kwa143*' _\" j8 ]* o% z5 V  s: {* @
    55.       Iua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3)*(u3/u2*KKua132*
      8 D' Q9 g0 `+ k. B3 ~, y. Y# u
    56.        Kua122 - u3^2/u2^2*Kua132*KKua122) + (betacl*Iua132*( c' C3 p$ o5 |& N2 c8 J
    57.       Kua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(w4/u3*KKwa143*# e/ Y% a# b. |\" ?  ]
    58.        Kua133 - w4^2*epsi3/u3^2/epsi4*Kwa143*KKua133) - (betacl*
      # S- N$ e/ p  n: O' l: r! _
    59.       Kua132*Kua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(w4/u3*KKwa143*! r& m; H. D$ ~5 U
    60.        Iua133 - w4^2*epsi3/u3^2/epsi4*Kwa143*IIua133);5 e8 K\" E' M# ]- f2 z1 z3 c! e
    61. ! ^  D. W6 [  o8 }8 W3 Y
    62. H2 = (betacl*Kwa143*, Q' R9 W; ^' [& Y\" b6 W& B
    63.       Kua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3)*(u3/u2*IIua132*
      3 B  g! Y$ L1 x& |7 E/ X' M. ^
    64.        Iua122 - u3^2/u2^2*Iua132*IIua122) - (betacl*Kwa143*
      & J; u\" K\" b9 q* |6 R0 h
    65.       Iua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3)*(u3/u2*KKua132*% v; Q9 r/ t( j: A( e
    66.        Iua122 - u3^2/u2^2*Kua132*IIua122) + (betacl*Iua132*1 S! _3 n7 G\" b& i+ i; {. W
    67.       Iua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(w4/u3*KKwa143*
      ) b0 ^9 v5 U) I2 g\" p- R; H6 }1 F
    68.        Kua133 - w4^2*epsi3/u3^2/epsi4*Kwa143*KKua133) - (betacl** g7 ?\" o! e\" m
    69.       Kua132*Iua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(w4/u3*KKwa143*
      / C, N, T. R! p9 a4 S9 g1 U\" a
    70.        Iua133 - w4^2*epsi3/u3^2/epsi4*Kwa143*IIua133);, }* f; P# N6 s4 N

    71. 6 h8 E: Q: c3 v9 b' w
    72. H3 = (betacl*Iua132*Kua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(betacl*, R$ j3 A: y7 E3 u5 Z- L
    73.       Kwa143*Kua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3) - (betacl** V, b% g3 _' k. }' _
    74.       Kua132*Kua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(betacl*Kwa143*  Z9 B0 B4 p( ?1 X$ s
    75.       Iua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3) + (u3/u2*IIua132*
      3 R8 n# p8 w\" s\" p% D0 W5 d/ }
    76.        Kua122 - * X! E% I% A( [2 e5 m: E- _( o
    77.       u3^2*epsi2/u2^2/epsi3*Iua132*KKua122)*(w4/u3*KKwa143*Kua133 -
      8 R0 k, N+ |0 J7 W3 V/ Z9 B\" S. y
    78.       w4^2*epsi3/u3^2/epsi4*Kwa143*KKua133) - (u3/u2*KKua132*Kua122 - , g. u* `+ _3 `* ]# b) d- _  Y
    79.       u3^2*epsi2/u2^2/epsi3*Kua132*KKua122)*(w4/u3*KKwa143*Iua133 - ! N- J+ E7 Y- W5 |8 V# Z8 N3 \) p
    80.       w4^2*epsi3/u3^2/epsi4*Kwa143*IIua133);8 {) d* b$ X' M$ O$ s. `' ?6 y

    81. 6 M( i+ M7 ?& R, m4 V8 `
    82. H4 = (betacl*Iua132*Iua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(betacl*7 n4 B8 }1 B1 `( K* [# k) f
    83.       Kwa143*Kua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3) - (betacl*
      & W2 J7 b. q  ?. B& m2 @: C4 n
    84.       Kua132*Iua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(betacl*Kwa143*
      6 c9 ^% G( J8 q$ }2 a: Q
    85.       Iua133*(w4^2/u3^2 - 1)/omega/epsi4/u3/a3) + (u3/u2*IIua132*1 q. k. u! R2 a7 V' m- J8 e
    86.        Iua122 - 9 i- t% T2 i0 f/ ~
    87.       u3^2*epsi2/u2^2/epsi3*Iua132*IIua122)*(w4/u3*KKwa143*Kua133 -   c( D& C: \) m4 p
    88.       w4^2*epsi3/u3^2/epsi4*Kwa143*KKua133) - (u3/u2*KKua132*Iua122 -
      * U# Q9 H: w3 o: x
    89.       u3^2*epsi2/u2^2/epsi3*Kua132*IIua122)*(w4/u3*KKwa143*Iua133 -
      - y$ K) U* p% K3 ^* K; x1 [& c
    90.       w4^2*epsi3/u3^2/epsi4*Kwa143*IIua133);: R+ ]# M, T. D& R
    91. / K0 _  A( z+ O# k, R
    92. M1 = (betacl*Iua132*Kua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(betacl*
      0 u. b7 q7 H- {
    93.       Kwa143*Kua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3) - (betacl*Kua132*. F4 M: G\" P- O5 j. ?
    94.       Kua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(betacl*Kwa143*, x5 a3 z- p- x: B; t# X9 I' H3 Y
    95.       Iua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3) + (u3/u2*IIua132*Kua122 -5 _9 e. D, A\" f7 c3 ~- _3 u
    96.        u3^2/u2^2*Iua132*KKua122)*(w4/u3*KKwa143*Kua133 - . a3 c' w\" `+ y+ C* L2 R2 P
    97.       w4^2/u3^2*Kwa143*KKua133) - (u3/u2*KKua132*Kua122 - & v4 [3 K, V- b. `4 }
    98.       u3^2/u2^2*Kua132*KKua122)*(w4/u3*KKwa143*Iua133 - ) R- H; m) `3 l9 E  F% E
    99.       w4^2/u3^2*Kwa143*IIua133);0 p2 n4 a1 p; d) m5 X

    100. . Z9 q& L$ x) T; f/ k8 N- S) H
    101. M2 = (betacl*Iua132*Iua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(betacl*! Y9 y, [: U9 x2 }
    102.       Kwa143*Kua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3) - (betacl*Kua132*
      ( p5 {) ?$ N6 D% q- c: u
    103.       Iua122*(u3^2/u2^2 - 1)/omega/epsi3/u2/a2)*(betacl*Kwa143*
      1 W( C8 b3 l0 P& y$ s' V+ U
    104.       Iua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3) + (u3/u2*IIua132*Iua122 -, `: p/ Z  V4 ]
    105.        u3^2/u2^2*Iua132*IIua122)*(w4/u3*KKwa143*Kua133 -
      9 P' g0 i6 g% i4 H
    106.       w4^2/u3^2*Kwa143*KKua133) - (u3/u2*KKua132*Iua122 - 7 o- I& }; @* a9 ~. Y# k' V! W
    107.       u3^2/u2^2*Kua132*IIua122)*(w4/u3*KKwa143*Iua133 - 7 v; s- Q' @# ~- ^' W7 o4 f
    108.       w4^2/u3^2*Kwa143*IIua133);
      1 N9 _2 A6 w; h- q2 }

    109. 9 x& y) a6 E8 k
    110. M3 = (betacl*Kwa143*% }% w! W! c$ R
    111.       Kua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3)*(u3/u2*IIua132*Kua122 -
      5 `: ~0 T8 R\" Z\" R& H. @
    112.       u3^2*epsi2/u2^2/epsi3*Iua132*KKua122) - (betacl*Kwa143*+ q  i. ]% H0 `( B9 W0 R' m
    113.       Iua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3)*(u3/u2*KKua132*Kua122 -   K2 f  C/ t, K' u; W% U) ^
    114.       u3^2*epsi2/u2^2/epsi3*Kua132*KKua122) + (betacl*Iua132*8 @1 W$ m( F* N% @! a3 u\" s! x
    115.       Kua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(w4/u3*KKwa143*Kua133 - & b( f, t\" W7 s  e
    116.       w4^2/u3^2*Kwa143*KKua133) - (betacl*Kua132*
      \" I# \$ l! H+ ]% P
    117.       Kua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(w4/u3*KKwa143*Iua133 -
      ' X+ d/ h\" B% t; I+ _4 m
    118.       w4^2/u3^2*Kwa143*IIua133);0 a! Q* J; R0 Q, b& f2 r

    119. 0 B, `\" t\" |4 t& U0 R\" z# v
    120. M4 = (betacl*Kwa143*. O- X+ z& E2 r( R) A, D
    121.       Kua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3)*(u3/u2*IIua132*Iua122 - 9 z/ T; S1 J  B+ U0 t
    122.       u3^2*epsi2/u2^2/epsi3*Iua132*IIua122) - (betacl*Kwa143*' |' L\" N! E0 }  H) }8 d7 l
    123.       Iua133*(w4^2/u3^2 - 1)/omega/mu/u3/a3)*(u3/u2*KKua132*Iua122 -
      7 y2 ]' u# N+ c
    124.       u3^2*epsi2/u2^2/epsi3*Kua132*IIua122) + (betacl*Iua132*1 l9 c3 e  W8 m! G4 X( b* N) n
    125.       Kua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(w4/u3*KKwa143*Kua133 -
      + n) n% d7 H\" @, C
    126.       w4^2/u3^2*Kwa143*KKua133) - (betacl*Kua132*
      & j9 E( k( N# M, J
    127.       Iua122*(u3^2/u2^2 - 1)/omega/mu/u2/a2)*(w4/u3*KKwa143*Iua133 - 3 x: q! G; \5 N/ E; h0 t
    128.       w4^2/u3^2*Kwa143*IIua133);
        i5 c% m+ c5 S* [1 _# b' ~
    129. 8 F' D: X* e+ j: [/ g. Z. s9 p) O
    130. R1 = u2^2/u1^2*Iua121*IIua111 - u2/u1*IIua121*Iua111;
      ! q, T. Q0 c. Y; n. {, N, T1 V; n, R$ i
    131. T1 = u2^2/u1^2*Kua121*IIua111 - u2/u1*KKua121*Iua111;
      2 B+ ]3 O2 ]7 h% y0 h* U0 s
    132. U1 = betacl*Iua121*Iua111*(u2^2/u1^2 - 1)/omega/epsi2/u1/a1;
      $ h\" E- b+ d( c5 {. l. p) E\" S' c
    133. V1 = betacl*Kua121*Iua111*(u2^2/u1^2 - 1)/omega/epsi2/u1/a1;
      9 N5 |! y% ~. S: j

    134. 8 S* [1 c  x3 t0 B\" \2 @, c
    135. R2 = u2^2/u1^2*epsi1/epsi2*Iua121*IIua111 - u2/u1*IIua121*Iua111;2 ~0 m8 D, o/ b0 h
    136. T2 = u2^2/u1^2*epsi1/epsi2*Kua121*IIua111 - u2/u1*KKua121*Iua111;
      , o2 V' D3 G/ F/ p% `
    137. U2 = betacl*Iua121*Iua111*(u2^2/u1^2 - 1)/omega/mu/u1/a1;! F# a4 ]6 S0 _7 y) _( F
    138. V2 = betacl*Kua121*Iua111*(u2^2/u1^2 - 1)/omega/mu/u1/a1;
      + v1 {& U( W$ Y/ I+ F! r

    139. 4 w7 o  w% P' B( f% r
    140. xicl1 = (-R1*H1 + T1*H2 + U1*H3 - V1*H4)/(R1*M1 - T1*M2 - U1*M3 +
      \" }3 x6 r8 z2 v( |% M& Z
    141.      V1*M4);; x$ O# q( _# w* E( t
    142. xicl2 = (-R2*H3 + T2*H4 + U2*H1 - V2*H2)/(R2*M3 - T2*M4 - U2*M1 + 3 N8 W1 @  y2 X3 D2 U- t* [/ S9 a6 K
    143.      V2*M2);
      # V9 B4 v2 a  Q: ~
    144. # @2 z& |( I3 D# N
    145. x = xicl1 - xicl2;
      ; _6 A) ]  R  b( s* x( E
    146. x1 = Re[x];
      ( i, v% R\" w\" c3 s
    147. x2 = Im[x];) M) ~6 U4 W: K, k& i# F* Q5 S
    148. ) i' Y( i% }1 V9 C: d
    149. FindRoot[{x1,x2},{{neffclre,1.333},{neffclim,0.00001}}];
      5 s+ H; o3 N. U( |. V' d- T\" M0 S! \
    150. ]
      # @$ I- ~) K! @' [8 F$ W
    151. 1 W9 j5 Y3 A% f1 ?2 L4 x# d
    复制代码
    代码如上,结果是{neffclre -> 1.33017, neffclim -> 0.0000172055}& [9 N6 l: n4 L# i" s
    但我把FindRoot[{x1,x2},{{neffclre,1.333},{neffclim,0.00001}}];
    & f! z  _0 ?* }8 K. S* `换成& L, x3 ^$ @1 j: S$ C
    For[i = 1, i < 133, i++, neffclbase = 1.330 + 0.001*i;
    $ ~( E; R, u) r) K FindRoot[{x1, x2}, {{neffclre, neffclbase}, {neffclim, 0.00001}}];6 E. H: [0 p- Z
    ]
    % ?0 h' o% A& J& e9 V, ?9 _就会出现
    ( ?" z1 Q! R* D2 ]) @# vFindRoot::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.
    0 c) E' d3 j5 ?3 j. x. B& W
    $ g* ]; e/ u: x3 C# W. }2 o* F0 e+ S请问是怎么回事?+ B' L$ `4 x! ]: u% {( r) b" M

    2 L* Z0 X1 i6 k
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