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Nov 01, 2014
fysikoblog.blogspot.com
4.
&
! , . , . ; , , . , , 33 ! , . , , , , . , , ; ; , ( ) ( , ), . ! , . . . , . . . material dispersion. , .
fysikoblog.blogspot.com
4.1. , . ; , , , (bound) . , - . , . , . , , c - . , , . , , , .
4-1-1 : . , . . , , ( ) . , 0 2, .
4.2
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. , ! . . , , 1014 Hz. , , . , , : 2 E 0 0 2E =0 t 2
(4.1.1)
. (4.1.1) (1.2.2) : =c=1
0 0
(4.1.2)
(0) (0) . , () () . [ 1.2.]. (4.1.1) : 2 E 2E =0 t 2
(4.1.3)
:
=
1
(4.1.4)
, = ik & / t = i , :
=
k
= ph
(4.1.5)
(phase velocity). n (c) . : n = c/ph (4.1.6)
4.3
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e= /0 m= /0, :n = 1/ o 1/
=
= e m e
(4.1.7)
- . , ( 3.5). e , 0, e = 0, :n = e
n 2 = e = 1 + e
(4.1.8)
, , , e, . , . , .. , () (). , , , . , , . ( ) , , (4.1.7), , . , ( 4.3.2.). . , , , . , , . x, :p = qx
(4.1.9)
P . , :P = N p = Nqx
(4.1.10)
4.4
fysikoblog.blogspot.com
&
- - , :
P
=
&
o e
E
(4.1.11)
- . o e , . , -: ( ) ( ). , 7.4.3. o e , ( 3.5.). . , , :D = o E + o e E = o E
(4.1.12)
:n 2 = e = 1 + e = 1 + P o E
(4.1.13)
4.1.1. Lorentz , Lorentz. [ Hendrik Antoon Lorentz 1878, Nobel 1902]. : , , . xyz, . , , .
4.5
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4-1-2 : . , (resonant frequencies) , . - 0 s m :
0 =
sm
s = m02
(4.1.14)
E = E0 exp ( it ) Coulomb :Fe = qE = qE0 exp ( it )
(4.1.15)
x . - ,
:Fs = s x = m02 x
(4.1.16)
(damping force) :FT = m = m dx dt
(4.1.17)
:d 2x F = Fe + Fs + FT = m 2 dt
(4.1.18)
Fe Fs
Coulomb
E
q x
4-1-3 : , . H :
4.6
fysikoblog.blogspot.comqE0 exp ( it ) m02 x m dx d 2x =m 2 dt dt
&
qE d 2x dx + + 02 x = 0 exp ( it ) (4.1.19) 2 dt dt m
:x = x0 exp ( it ) = q E0 exp ( it ) qE = 2 2 2 m (0 i ) m (0 2 i )
(4.1.20)
. 0 . (4.1.20), , :P = N p = Nqx = Nq 2 E m (02 2 i )
(4.1.21)
(4.1.13) :
p Nq 2 1 2 = 1+ 2 n ( ) = 1 + 2 0 2 i m o 0 i2 2
(4.1.22) (4.1.23)
:
p = Nq 2 m o
(plasma frequency) . , . , (dispersion relation). , i. n = n + i n . n , : n 2 1 = ( n + 1) ( n 1) 2 ( n 1) :n ( ) = 1 +2 p
(4.1.24)
2
(02
02 22 2
)
+ ( )
2
&
( ) =
2 p
2
(02 2 ) + ( )2
2
(4.1.25)
. , 02. .
4.7
fysikoblog.blogspot.com
( f1 01, f2 02 ), (4.1.22) :fj fj Nq 2 2 n ( ) = 1 + 2 = 1+ p 2 2 m o j 0 j 2 + i j j 0 j + i j2
(4.1.26) (4.1.27)
:
fj
j
=1
, q B . , . ( ) . . , .
4.8
fysikoblog.blogspot.com
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4.2. , :k =
c
n =
c
( n i ) =
k i
c
(4.2.1)
z, :
E = E0 exp i t kz + = E0 exp
(
)
z exp i ( t kz + ) c
(4.2.2)
z : z ' E0 = E0 exp c
(4.2.3)
m k0 0 k0
0
km
4-2-1 : . , , :I E E* = Eo2 exp 2
z = I o exp ( a ( ) z ) c
(4.2.4) (4.2.5)
:
a ( ) =
2 ( ) c
o (absorption coefficient) . : 1 c = (4.2.6) a ( ) 2 ( ) , (absorption depth), 1/e .
4.9
fysikoblog.blogspot.com
. (), (absorption index), . (4.1.19) , . , August Beer Johann Heinrich Lambert : eer-Lambert: .
(4.2.4) :I ln = a ( ) z I0
(4.2.7)
4-2-2, . I0 d1 ( 4-2-2). Id1, , z d1. d2 ( 4-2-2), Id2 (4.2.4) , z d2.d1
A (R)
A (R)
d2
(T)
(T)
4-2-2 : . Id /I0 d , Beer. .
4.10
fysikoblog.blogspot.com4.3.
&
( ) , : =dn ( ) d
(4.3.1)
, =2 =2c/, n(), n(), n() . , n .
4.3.1. (4.1.24) n() () :n ( ) = 1 +2 p
2
(
02 22 0
2 2
) + ( )
2
( ) =
2 p
2
(
2 0
2 2
) + ( )
2
(4.3.2)
, ^, =0. , . ; . (4.3.2) :n =0 ( ) = 1+2 p
2
(02
02 2
2 2
)
= 1+
2 p
1 2 2 2 0
(4.3.3)
- . : , :n =0 ( = 0 ) =
(4.3.4)
0, .. n(=0) ! =0, , . (normal dispersion). , , .
4.11
fysikoblog.blogspot.com
n
0
4-3-1 : . . . , 0 ( .. 0) , . , , , . , , , . - 7.1.2. 4-3-2 n , (4.3.2).
n 1
4-3-2: . . .
4.12
fysikoblog.blogspot.com
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.. n , .. , (anomalous dispersion). , . , . , j 0, |0| ^ 0 202j 2 0(-0), (4.3.2) :2 2 p p 0 & ( ) = n ( ) = 1 + 2 2 2 4 0 ( 0 ) + ( / 2 ) 80 (0 ) + ( / 2 )2
(4.3.5)
() = 0, . ( ) (4.3.5) , :2 p n ( ) MAX = 1 + 40
&
2 p n ( ) MIN =1 40
(4.3.6)
=0!/2, . +0, p, .
4.3.3. : ( , h=21) , . .
4.16
fysikoblog.blogspot.com
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h1 4-3-4 : .
h1
( , h21) . . . .
h1 4-3-4 : .
h1
. (continuous spectrum) ( 4-3-5) , ( ..). (. ) , . , (linear discrete spectrum) . , , convoluted . (.. ) , . . , . (emission spectrum) ( 4-3-5) . , (absorption spectrum) , ( 4-35). . !
4.17
fysikoblog.blogspot.com
, . , ( 7.1.2). , . .
4-3-5 : () () () . . % ( , % ) . , 100% , 600 nm, . , . . , 500 nm, 100% 500 nm, 550 nm. . , , . , . : , , . , . 450 nm 650 nm, ,
4.18
fysikoblog.blogspot.com
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. - , !100
(%)
50
(nm)400 500 600 700
0
(%)
100
50
(nm)400 500 600 700
0
4-3-6 : () () . , . , , . , (carotenoids), , (anthocyanins), , . , .
Newton (Optiks, 135).