Теории / Садовский М.В. Диаграмматика (2005)
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S = T G(ε1p1)D(ε − ε1 |
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ε |
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*!! % ! ! ! iεn = i(2n + 1)πT & G ( !* *
* # * I&IL & 6 * ! # ε
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f (z) = G(z, p1)D(ε − z, p − p1)th |
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! ) z = iεn = i(2n + 1)πT ! W
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! ! ( %* f (z) & H I&J ! # # ! & f (z) ) zn = i(2n + 1)πT
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Resz=zn f (z) = 2T G(zn, p1)D(ε − zn, p − p1) |
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I&J I = 4πiS *) *) *!!*
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. & I& W 1. * 2 * # * ! *!!
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1 2 *) ! ! W
I = |
−∞ dε1 |
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M ε = i(2n + 1)πT ! ! # th ε−ε1 |
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2T |
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GR(εp) − GA(εp) = 2iImGR(εp) |
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+,-W |
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ω − ε iδ |
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GR(A)(εp) = π −∞ |
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G ( I&JJ * !W |
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− iδ |
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2T + |
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Σ(εp) = (2π)4 |
π dε1dωd3p1 |
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ω1−1ε + ε1 |
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g2 |
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ImGR(ε p )ImDR(ωp |
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ω −1 |
ε + ε1 |
− iδ |
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ImGR(ωp )ImDR(ε1p |
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3 ! ! ! ε1 ω ! ! ! !
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π |
dε1dωd3p1 |
ω1 1ε + ε1 |
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th 2T |
+ cth 2T I&JL |
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Σ(εp) = (2π)4 |
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g2 |
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F F J C |
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ε T ωD |
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iεn → ε + iδ * W |
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ImΣR(ε) ζ |
T 3 |
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% * ( ( $ % !
ε ωD T ωD ! # ! ! ! !
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ImΣR(ε) ζ |
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c2p2 |
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G ε ωD I&JL * W |
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ImΣR(ε) = const ωD |
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*) * !*) % ! . & I& & / ! |
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Γ(1) = −g3 |
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G(p1ε1)G(p1 + k, ε1 + ω)D(ε − ε1, p − p1) (2π)4 |
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d3p1dε1 |
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G ! * *) * ( & . ! ! ε1&
G ! * # ! % ! kD pF * D(ε−ε1) |ε−ε1| ωD * !
# |ε − ε1| ωD & 5 ε1
ωD ! ! ! #W
Γ(1) g3ωD |
(ε1 |
− ξ(p1) + iδsignξ(p1))(ε1 |
+ ω |
1− ξ(p1 + k) + iδsignξ(p1 + k)) |
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d3p |
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3 pF2 |
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pF & G ( !* ! # ! |
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g ωD |
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QJ |
. F - >JK<= L G<=<==< M/0 <1 N J 0 |
. & I& W G ( $ % ! &
. & I&QW G ( $ % !
1 ! * # $ ! !2 &
S # ( W
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# ωD |
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EF |
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M & ! ( !* ! |
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! ! 1 ! * # $ ! !2 & #
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%* 8 % ( W |
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D(kt) = |
dω |
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ick |
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D(ωk)e−iωt = − |
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e−ick|t| |
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2π |
2 |
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G(pt) = −ie−iξ(p)t |
θ(ξ(p)) |
t > 0 |
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−θ(−ξ(p)) |
t < 0 |
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G(pt)&
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Γ(1) = −g3 |
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(2π)3 |
dtG(p1, t − t1)G(p1 + k, t2 − t)D(p − p1, t1 − t2) |
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d3p1 |
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EF & H ! ! ( |
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! E−1
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# * ! ! ! (
!W
g2Π0 |
(ωk) = −(2π)4 |
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(E − ξ(p) + iδsignξ(p))(E + ω − ξ(p + k) + iδSignξ(p + k)) |
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2ig2 |
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dEd3p |
I& O
! * *
& J # * ! !W
g2Π0 |
(ωk) = − π2 |
1 − 2vF k ln |
ω |
vF k |
+ 2v|F k| |
θ |
1 − v|F k| |
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g2mpF |
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+ vF k |
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ω |
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3 * I&,Q % %* 8 ! ! !
* 6 W
D−1(ωk) = D0−1(ωk) − g2Π(ωk) |
I& , |
Q |
. F - >JK<= L G<=<==< M/0 <1 N J 0 |
' % * ! D−1(ωk) = 0& G # *
# * ! # ( N ! !
# ω vF k& 5 )
% *) $ ( *) # # !
(ω = 0) #W
g2Π0 |
≈ − |
g2mpF |
= −2ζ |
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π2 |
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' I& , W |
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D−1(ωk) = D−1 |
(ωk) |
− |
g2 |
Π = |
ω2 − c02k2 |
+ 2ζ |
I& I |
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c02k2 |
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0 |
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c0 $ 1 # * 2 1 ! 2 % !
ω = ck # * W
c2 = c02(1 − 2ζ) |
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! ( $ % ! 1 ! 2
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% ! ) ! !*! % !
! ! ( ! &
o ( @$+ (ω2 < 0K+ ζ > 1/2 & 8
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% 3 ' λ
ζ ! =
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λ = ζ |
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ω2 |
1 − |
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9 % λ ≈ ζ ζ 1 ζ λ 8
! -0 %
ζ < 1/2 ' λ > !
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λ 9 ( @?+
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λ |
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" λ > 0 ' ζ < 1/2 |
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< -"0 < " ω0(k) = c0k '
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ω2 |
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D(ωk) = |
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( @B+ |
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ω2 |
− ω2 |
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ω(k) 3 ' 6 % 3 ' 8
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dkk ω2 |
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λ = ζ |
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2pF2 ω2 |
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M Π0 k ( @7+( @H+ ( @?+ λ "
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6 * % * ! # ! !*) #
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g2ImΠ (ωk) = |
− |
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I& O |
0 |
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F O L ? 2 ? H B |
. & I&LW K
! q ( !
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G ( * 6 % %* 8
! # * # ω = ck + iγ *
* #W |
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c2 |
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π |
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γ = |
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I&Q |
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U * #! % ! |
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) Reω ! * c/vF |
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m/M & |
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ηω2 |
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ρc3 |
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( B)+ |
η 3 ρ 3 % % 3 '
%'' % = η(ω) ω−1 < 8
%'' % 3 "
% ω < ck '
* * ! # q = 2pF |
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Π0(q0) |
! %! *) # ∂Π0(q0) |
|q=2pF & |
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∂q |
# ! *! ! d = 2
! ! * d = 1 ! %! # ! !
! Π0(q0) :&3&:% # &3&K ,O W
Π0(q0) ln |q − 2pF | I&Q
K Π0(q0) ! . & I&L&
4 ! !& ! ! * #
* * !* % %* 8 * !
! ( ! ! W
D(ωq) = |
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1 |
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ω02(q) |
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(ωq) − g |
2 |
Π0(ωq) |
ω2 |
− |
ω2 |
(q) |
− |
g2 |
ω2 |
(q)Π (ωq) |
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D0 |
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% ! W |
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ω2(q) = ω02(q)[1 + g2Π0(ωq)] |
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I&QJ |
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5 Π0(q0) → −∞ |
q = 2pF |
* |
d |
= 1 |
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q = 2pF - (ω |
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QL |
. F - >JK<= L G<=<==< M/0 <1 N J 0 |
. & I&OW H ( *) !
# &
! ! ! g& /-4
! *) ) % !
* * ! ! Q = 2pF & & ! L = 2π
Q &
! -1 * # # !* ! ) !
! & 6 d = 3 # # # *
! %
q = 2pF ;&u<aD ,O O ! 1 2 !
d = 1 1 2 ! & 5 !
# ) ) % ! ( ! * * !*
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6 ! ! * * ) ! ( !
2
! ε(p) = 2p & ! # ! (
m
! # ! *) N ! #
) % ! (d = 3) * ! (d = 2)& Z ! ) #
*) % !*& N ! ! * #
* & 4 ! d = 2 #
! ! W |
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ε(p) − µ = −2t(cos pxa + cos pya) − µ |
I&Q |
t $ ! * #
& H ( T )( *
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( . & I&O& µ = 0 * |
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( ! # N ! ! & 6 |
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0 |
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πa , πa |
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( ! * Π0(q0) ! q → |
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1 2 ! % |
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# |
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# 1 ! 2 W Π (q0) |
ln |
q |
Q Q = |
π , π |
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* 1 2 !
* # N ! ! * ! 1 !2 DCrEBDm &
/ d = 1 ! %
% ±pF " 1 %
F C 2 C C QO
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& ! ! Q = |
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( W |
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ε(p + Q) − µ = −ε(p) + µ |
I&Q |
) * ! & ! ! I&Q *
=0 * Q = πa , πa & : !
! ( !* * ) * # GK
d = 3 I&Q W
ε(p) − µ = −2t(cos pxa + cos py a + cos pz a) − µ I&QQ
µ = 0 Q = πa , πa , πa & G # N ! ( ! * !
! * &
* !
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! % *) *
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! Q&
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( ! * ! ! !& ' ! ! !
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( & G ! # * ( (
1 2 % # ) ( ! ( $ % ! & H ( $ ! # ! W
H = k |
Ekak+ak + qλ Ωqλ |
bq+λbqλ + 2 |
+ |
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1 |
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+gkk λa+k ak bk−k λ + b+k −kλ +
kk λ
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akap |
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2 pkq |
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Vq = |
4πe |
2 |
Ek $ ( ( ! * ! |
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2 |
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q |
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W |
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2m + |
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Vei(r − Rn) + UH (r) ψk(r) = Ekψk(r) |
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n |
I&QO |
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k2 |
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Vei(r − Rn) ^ ( $ ! UH (r) ^
! ( ! Ωqλ ^ 1 2
! &
L . F - >JK<= L G<=<==< M/0 <1 N J 0
) * *
! !W |
4πn(Ze)2 |
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Ωqλ2 = |
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n $ # Z $ M $ ! & ! ( #
# ! &
K ( $ % ! gkk λ
W
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− M Ωkλ |
1/2 |
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gkk λ = |
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< k iVei k > eqλ, |
(q = k k ) |
I&L |
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2 |
eqλ $ % & 4 * #
! ( gkk2 λ ! *
# 1 * 2 W
gkk2 λ |
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k )2 |
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5 # * ! ! ! * ! ( * ) * & 6 * ! (
! ! * # bcd $ W
V(qω) = |
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q2 e(qω) |
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4πe2 |
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e(qω) = 1 − |
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Π0(qω) |
I&L |
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q2 |
$ ( ! # ( & ' *)
!! . & &J e & : ! !
( . & I&, ! # ( ( $ %
W |
g(q, λ) |
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g˜(q, λ) = g + gVq Π0 + gVqΠ0Vq Π0 + ... = |
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e(qω) |
1 2 % # * 6
. & I&,,W
D−1(qλ, ω) = D−1 |
(qλ, ω) |
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g2Π (qω) |
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g2Π (qω)V Π (qω) |
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... = |
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= D0−1(qλ, ω) − |
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e(qω) − 1 |
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g2(q, λ) |
1 |
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Ω2 |
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D0(qλ, ω) = |
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qλ |
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I&LL |
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ω2 − Ωqλ2 |
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+ iδ |
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> ! " λ = 1, 2, 3 9 " 8
" "
% =
Ωqλ2 = |
4πn(Ze)2 |
( H)+ |
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M |
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λ |
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