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    1

    ............................................................................................................... 2

    ....................................................................................... 21.2 ............................................................. 2

    ...................................................................................... 2 ................................................................................................. 2 ........................................................................................... 21.2. ...................................................................... 2

    ..................................................................................................... 2 .............................................. 2 ................................................................ 2 .................................................... 2

    .......................................................................................................... 2 ............................................................................................................... 2 ................................................................................................... 2

    .................................................................. 3 ............................................................................... 3 ........................................................................................................... 3

    .............................................................................. 3 ................................................................................... 3 ....................................... 3

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    2

    CHNG

    1GII HI

    I CNH CH

    CC C I C I NG

    Mode

    I HI N

    1.3.1

    NG N

    CC N

    I I H HO

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    3

    CHNG

    2 N N NGNG I

    CC HNG NH MAXWELL

    I

    HNG NH N N NG

    HNG H

    -step Fourier Medthod)

    -difference Methods)

    CC N

    I I H HO

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    4

    CHNG

    3N N C NH

    CC CH N N HC NHAU

    222

    2,

    2 2

    A i Ai A A A

    z T

    (3.1.1)

    .g gv T t z v

    0 0 D NL D, LNL

    0:

    0 0,

    gt z vT

    T T

    (3.1.2)

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    5

    U:

    0, exp 2 , ,A z T P z U z (3.1.3)

    P0

    2 222

    sgn exp,

    2D NL

    zU Ui U U

    z L L

    (3.1.4)

    2sgn 1 2

    2

    0

    2 0

    1, .

    | |D NL

    TL L

    P (3.1.5)

    D NL

    NL D 2 2 1.U ( , ) (0, )U z T U

    n thng quang. Cho L ~ 50km, LD NL 0 0 2 . = 1.55m,

    2

    2 20 ps km 1 13W km

    0 0 ~ 1mW.Tuy nhin LD NL D LNL 0 0

    NL D

    2

    0 0

    2

    1.D

    NL

    P TL

    L

    (3.1.6)

    P0 2 = 1.55m.

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    6

    D NL 2 2 1.U )

    2

    0 0

    2

    1.D

    NL

    P TL

    L

    (3.1.7)

    0 0

    D

    NL

    -dispersion) (2 -dispersion) (2

    NG NG C NG N (DESPERSION-INDUCEDPULSE BROADCAST)

    2

    2

    2.

    2

    U Ui

    z T

    (3.2.1)

    2 /(2 (disper- -inducedspatial).

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    7

    ~1

    , , exp ,2

    U z T U z i T d

    (3.2.2)

    ~

    ~21

    22,Ui U

    z

    (3.2.3)

    ~ ~

    2

    22, 0, exp ,iU z U z (3.2.4)

    ~

    2

    22

    1, 0, exp ,

    2iU z T U z i T d

    (3.2.5)

    ~

    0, 0, exp ,U U T i T dT

    (3.2.6)

    3.2.1 Xung Gaus

    2

    2

    0

    0, exp ,2

    TU T

    T

    (3.2.7)

    T0 0

    1 2

    0 02 ln 2 1.665 .FWHMT T T (3.2.8)

    ta

    2

    0

    1 2 220 20 2

    , exp .2

    T TU z T

    T i zT i z

    (3.2.9)

    1

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    8

    1 2

    2

    1 0 1 ,DT z T z L (3.2.10)

    20 2D

    L T

    D

    i z = 2LD D

    D

    2

    ,U z T 0, 2LD D.

    ( ) ( ) [( )] (3.2.11)

    22 1

    2 2

    0

    sgn 1, tan .

    21

    D

    DD

    z L T zz T

    T Lz L

    (3.2.12)

    ,z T

    0. Sai phn T 0exp i t

    2

    2 2

    0

    sgn 2.

    1

    D

    D

    z L TT

    T Tz L

    (3.2.13)

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    9

    2 2 > 0), 2 < 0).

    2 > 0)

    2 < 0).

    3.2.2 Chirped Gaussian Pulses

    2. D c (3.2.7)]

    2

    2

    0

    10, exp ,

    2

    iC TU T

    T

    (3.2.14)

    - -

    0,U

    1 22 2 2

    0 020, exp .1 2 1

    T TU

    iC iC

    (3.2.15)

    -

    1 2

    2

    01 / .C T (3.2.16)

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    10

    2

    0

    1 2 220 20 2

    1, exp .

    2 11

    iC TTU z T

    T i z iC T i z iC

    (3.2.17)

    1/22 2

    1 2 2

    2 2

    0 0 0

    1 .T C z z

    T T T

    (3.2.18)

    min 2.

    1D

    Cz L

    C

    (3.2.19)

    min 01 1 2

    2

    .

    1

    TT

    C

    (3.2.20)

    2

    2

    0 0

    0, sech exp ,2

    T iCT U T

    T T

    (3.2.21)

    0 02ln 1 2 1.763 .FWHMT T T (3.2.22)

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    11

    2

    0

    10, exp ,

    2

    m

    iC TU T

    T

    (3.2.23)

    0 0(ln 9) .2

    r

    T TT

    m m (3.2.24)

    1/222 ,T T

    (3.2.25)

    2

    2

    ,.

    ,

    p

    pT U z T dT

    TU z T dT

    (3.2.26)

    1/2

    2 22 2

    2 2

    0 0 0

    1/ 2 2 1/ 21 1 ,

    3 / 2 3 / 2

    m mC z zm C

    m T m T

    (3.2.27)

    3.2.4 Super-Gaussian Pulses

    N C C A

    2 3

    32

    2 3.

    2 6

    iU U Ui

    z T T

    (3.3.1)

    ~

    2 3

    2 3

    1, 0, exp ,

    2 2 6

    i iU z T U z z i T d

    (3.3.2)

    ' 3

    0 3/ .DL T (3.3.3)

    2

    , , exp ,I z U z T i T dT

    (3.3.4)

    2

    0lim ( , ) , .

    nn n

    nI z i T U z T dT

    (3.3.5)

    ~

    0lim , ,

    n nn

    n

    c

    iT I z

    N

    (3.3.6)

    2 2

    , 0, .cN U z T U T dT

    (3.3.7)

    ~ ~ ~

    , , ' * , ' '.I z U z U z d

    (3.3.8)

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    12

    ~ ~

    * , , .

    n nn

    n

    c

    iT U z U z d

    N

    (3.3.9)

    1/2

    2 22~30 0

    2 3

    2, exp .

    1 2 1 6

    T iTi iU z z z

    iC iC

    (3.3.10)

    1/22 2 2

    22 32 2

    2 2 3

    0 0 0 0

    11 1 ,

    2 2 2 4

    zC z zC

    (3.3.11)

    1/2

    1/2 22 '

    0 1 1 / 2 / ,D D DC L L z L

    (3.3.12)

    2 2 2

    22

    2 2 2 32 2

    2 2 2 3

    0 0 0 0

    11 1 1 ,

    2 2 2 4

    zC z zV C V

    (3.3.13)

    -Shape Pulses)

    ,U

    i HUz

    (3.3.14)

    2 3

    32

    2 32

    .! 2 6

    nn

    n

    iiH

    n T T T

    (3.3.15)

    , ,

    d T

    i H Tdz (3.3.16)

    2

    , , ,d T

    H H Tdz

    (3.3.17)

    0 1 ,T a a z (3.3.18)

    2 2

    0 1 2 ,T b b z b z (3.3.19)

    *

    0 0 0

    ,a U T TU T dT

    (3.3.20)

    *1 0 0, ,a i U T H T U T dT

    (3.3.21)

    * 20 0 0 ,b U T T U T dT

    (3.3.22)

    * 21 0 0, ,b i U T H T U T dT

    (3.3.23)

    * 22 0 01

    , , ,

    2

    b U T H H T U T dT

    (3.3.24)

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    13

    2 2 2 20 0 2 2 012 , 3 .b T b T (3.3.25)

    1/2

    2

    2

    0 0

    1 ,6

    z

    (3.3.26)

    -Pulses Measurements)

    N N C

    3.4.1 - -Induced Limitations)

    1/2 1/2

    2 22 2

    0 2 0 ,L DL (3.4.1)

    1 4.BL D (3.4.2)

    1/222

    0 2 02 .L (3.4.3)

    1/2

    2 1/4.B L (3.4.4)

    1/2

    22 210 3 02

    4 .L (3.4.5)

    1/3

    3 0.324.B L (3.4.6)

    2 21 1 22 21

    , 0, exp ,2 2

    m

    iU L t U L L i t d

    (3.4.7)

    1 1 2 2 0.D L D L (3.4.8)

    21 1 22 2 31 1 32 20 0,L L L L (3.4.9)

    CC N I I H HO

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    14

    CHNG

    4I IN NG HM

    -

    -steepening.

    NG H C NG T0 LD LNL LD >> L > LNL T0 P0 > 1W).

    Trong ( , )U z T

    2

    2| | ,

    z

    NL

    U ieU U

    z L

    (4.1.1)

    Chi

    1

    0( ) ,NLL P

    (4.1.2)

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    15

    P0 n2 exp( )NLU V i

    20;

    z

    NL

    NL

    V eV

    z z L

    (4.1.3)

    V L

    ( , ) (0, )exp[ ( , )],NLU L T U T i L T (4.1.4)

    U(0,T)

    2( , ) | (0, ) | ( / ),NL eff NLi L T U T L L (4.1.5)

    Leff

    [1 exp( )] / ,effL L (4.1.6)

    NL

    L D Leff L. = 0,Leff =L.

    max T = U U(0,0)| = 1.

    max 0/ ,eff NL eff L L P L (4.1.7)

    LNL max =1. = 2 W-1

    km-1

    m LNL P0 0

    2( ) ( ) | (0, ) | ,

    effNL

    NL

    LT U T

    T L T

    (4.1.8)

    2 1 2

    0 0 0

    2( ) ( ) exp[ ( ) ,

    eff m m

    NL

    Lm T TT

    T L T T (4.1.9)

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    16

    max

    0

    ( )( ) ,

    mf mT

    T (4.1.10)

    1 1 21 1

    ( ) 2 1 exp 1 ,2 2

    m

    f mm m

    (4.1.11)

    max 0 max0.86 , (4.1.12)

    2

    0( ) (0, ) exp ( , ) ( ) ,

    NLS U T i L T i TdT

    (4.1.13)

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    17

    max

    1,

    2M

    (4.1.14)

    222

    0 0 ,rms (4.1.15)

    0

    0 ,

    n

    n S dS d

    (4.1.16)

    1 2

    2

    max

    0

    41 ,

    3 3

    rms

    (4.1.17)

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    18

    , exp ,S z i d

    (4.1.18)

    , * , , ,z U z T U z T (4.1.19)

    2

    2 2, 0, 1 1 | 0, | ,Z Z

    (4.1.20)

    2 20, exp 2 ,cT (4.1.21)

    Partial Coherence)

    4.2 NH HNG C N N C NHM

    4.2.1 Pulse Evolution

    2

    222 2

    1sgn ,2

    zU Ui N e U U

    (4.2.1)

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    19

    0, = ,Dz L T T (4.2.2)

    22 0 0

    2

    .D

    NL

    PTLN

    L

    (4.2.3)

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    20

    1 22

    2

    max max 2

    0

    41 2 1 ,

    3 3D D

    L L

    L L

    (4.2.4)

    2 2

    2

    2 2

    ** ,

    2

    p

    pd T i A A

    T A A dT dz W T T

    (4.2.5)

    2,

    2

    pSd

    zdz

    (4.2.6)

    41

    0, ,pS A T dT W

    (4.2.7)

    2 2 210 22 ,pz S z (4.2.8)

    22

    2,

    2

    U d Ui U U

    Z

    (4.2.9)

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    21

    0( , ) , exp , ,T

    U z T z T i v z T dT (4.2.10)

    4.2.3 Optical Wave Breaking

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    22

    3 __

    22

    3 3sgn ,

    ' 6

    zU i Ui N e U U

    (4.2.11)

    3'__2 0 0

    3

    .D

    NL

    P TLN

    L

    (4.2.12)

    2 3 max / 2 , (4.2.13)

    HI NG HI N C CAO

    22 3

    2 22 3

    2 ' 3

    sgn sgn,

    2 6

    z

    R

    D D NL

    UU U U ei i U U is U U U

    z L L L

    (4.3.1)

    2 3'0 0

    2 3 0

    1, , ,

    D D NL

    T TL L L

    P (4.3.2)

    0 0 0

    1, ,RR

    Ts

    T T

    (4.3.3)

    -Steepening)

    2 2

    .

    U

    s U U i U U z

    (4.3.4)

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    23

    3 0,I I

    sIZ

    (4.3.5)

    ,sI IZ

    (4.3.6)

    , 3 ,I Z f sIZ (4.3.7)

    20, exp .I f (4.3.8)

    2

    , exp 3 .I Z sIZ (4.3.9)

    1 2

    20.39 .

    3

    NLes NL

    Lz L s

    s (4.3.10)

    2

    1 2

    0, exp , .S I z i z i d

    (4.3.11)

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    24

    4.3.3 Intrapulse Raman Scattering

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    CC N

    I I H HO