Ch4. Fields And Waves In Material Media

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Ch4. Fields And Waves In Material Media
Conductors and Semiconductors (??????)
Dielectrics (????) Magnetic Materials (????)
Wave Equations and Solution for Material Medium
(??????????????) Uniform Plane Waves in
Dielectrics and Conductors (??????????????)
Boundary Conditions (????) Reflection and
Transmission of Uniform Plane Waves
(???????????)
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4.1 Conductors Semiconductors (??????)
?
?
??? (????)
???
??
???
??
?0
3
??? (??,???)
???(?,??)
????(???)
10?20
10?15
10?10
10?5
100
105
1010
? (S/m)
4
??????????
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??????????
? ? ? ? ? ? ? ? ? ? ? ? ? ?

6
?? ? ???? n ? ???? vd ???
?


I

I



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??? ? ????? vd
e


I

I



?
t??
?
8
???? (conductivity)
e


I

I



?
?
?
9
???? (conductivity) ? ???? (resistivity)
? 1/?
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????(Hall effect) ?????? n
I
?

?

?
?

?

?

?

?
z

y
?
?
I
x
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4.2 Dielectrics (????)
????(electric dipole moment)


?
?
12
??????????
?

?
13
???????????

?
?
?
14
???????????
- - - - - - - - - - - - - - - - -

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???????????
???polarization
- - - - - - - - - - - - - - - - -
electric susceptibility

???displacement flux density
- - - - - - - - - - - - - - - - -

permittivity
dielectric constant
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????(anisotropic)????????????
permittivity tensor
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4.3 Magnetic Materials (????)
???? (magnetic dipole moment)
I
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???? (magnetic dipole moment)
N
N
S
S
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???????????
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????(anisotropic)????????????
permeability tensor
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????????????
????
????
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??????????
N
S
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???????????
N
S
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???????????
N
S
25
???????????
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??(magnetic domain)??
??m0
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??(magnetic domain)??
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???????????
Domain wall rotation
Domain wall motion
Unmagnetized
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???????????
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???????????
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??????
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(No Transcript)
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4.4 Wave Equations and Solution for Material
Medium (??????????????)
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????????
??? z 0
? z 0
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????????
????sinusoidal wave, ?phasor?? Ex, Hy
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????????
?
??
, ??
? z ??
? ?z ??
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????????
??
?????
?? z ??
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????????
?, ? 0, , ? 0
?
?
?
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????????
?? (???)
??
?
??
??
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????????
E?H???
?? z ??
?, ?, ? ? ?, ? ???
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4.5 Uniform Plane Waves in Dielectrics and
Conductors (??????????????)
??
? ?
? ?
????
????? (perfect dielectrics)
E?H???
?????? (imperfect dielectrics)
E?H???
??? (good conductors)
E?H???
???? (perfect conductors)
??????
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??????
? ?
????? (perfect dielectrics)
E?H???
?????? (imperfect dielectrics)
E?H???
??? (good conductors)
E?H???
???? (perfect conductors)
?????
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4.6 Boundary Conditions (????)
?????Maxwells Equations
?????
????
?????
?????
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????? , ???? ? ????
?
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????? ????
?
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??????
?
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4.7 Reflection and Transmission of Uniform Plane
Waves (???????????)
????
????