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Title
Cou
lom
b B
lock
ade
as a
Pro
be o
fIn
tera
ctio
ns in
Nan
ostr
uctu
res
Har
old
U. B
aran
ger,
Duk
e U
nive
rsity
Coh
eren
ce:
quan
tum
-mec
hani
cal
inte
rfer
ence
of e
lect
rons
Cor
rela
tion:
caus
ed b
y el
ectro
n-el
ectro
n in
tera
ctio
n
inte
rpla
y be
twee
n e-
e in
tera
ctio
n &
qua
ntum
inte
rfer
ence
[cla
ssic
con
text
: dis
orde
red
syst
ems a
nd m
etal
-insu
lato
r tra
nsiti
on]
extre
me:
cry
stal
mor
e ty
pica
l: liq
uid
Q.D
ots
Exam
ple
#1:
Qua
ntum
Dot
s
Com
p. T
ech.
[C. M
arcu
s gro
up, H
arva
rd]
conf
inem
ent
i
nter
fere
nce
dens
ity w
iggl
es
in
tera
ctio
ns→
→→
⇒in
terf
eren
ce c
ontri
butio
n to
the
inte
ract
ion
ener
gy
expe
rimen
t: se
nsiti
vity
to sm
all p
aram
eter
cha
nge
(B, V
g, …
)H
ow b
ig?
Doe
s sha
pe m
atte
r?
Exam
ple
#2:T
rans
port
Thr
ough
Sin
gle
Mol
ecul
es (1
)
Sing
le m
olec
ules
mol
ecul
ele
ad 1
lead
2
VI•C
ondu
ctan
ce?
•I-V
curv
e?•e
-e in
tera
ctio
ns?
•Vib
ratio
ns?
•Dev
ices
?
Tran
spor
t Thr
ough
Sin
gle
Mol
ecul
es (2
)
Mol
ec E
lect
r
Com
p. T
ech.
[D. R
alph
and
P.M
cEue
ngr
oups
, Cor
nell]
Exa
mpl
e #
3:N
ano
–m
agne
tism
, sup
erco
nduc
tivity
, … (1
)
Nan
o-m
ag.,
supe
r.,•E
lect
ron-
elec
tron
inte
ract
ions
cau
se c
erta
in c
olle
ctiv
eph
enom
ena
whe
n su
ffic
ient
ly st
rong
•Doe
s qua
ntum
inte
rfer
ence
influ
ence
thes
e co
llect
ive
effe
cts?
(mag
nitu
de?,
spat
ial d
istri
butio
n?, b
reak
dow
n?, …
)
M
idea
l
M
real
Doe
s in
terfe
renc
e af
fect
the
dire
ctio
n of
the
mag
netiz
atio
nin
sm
all f
erro
mag
nets
?
Nan
o –
mag
netis
m, s
uper
cond
uctiv
ity, …
(2)
Nan
o-m
ag.,
supe
r.,In
terp
lay
of s
uper
cond
uctiv
ity a
nd d
isor
der
Supe
rcon
duct
ivity
cha
ract
eriz
ed b
y a
loca
l ord
er p
aram
eter
, the
gap
:
↑↓
∆r
rc
cr
~)(
For w
eak
diso
rder
and
wea
k co
uplin
g, ∆
(r) i
s ind
epen
dent
of r
But
, if d
isor
der i
s stro
ng, i
nter
fere
nce
dest
roys
supe
rcon
duct
ivity
the
supe
rcon
duct
or –
insu
lato
r tra
nsiti
onca
lcul
atio
n of
∆(r
):sc
hem
atic
:
[Gho
sal,
Triv
edi,
and
Ran
dier
i]
OU
TLIN
E
Out
line
-mas
ter
Com
p. T
ech.
Intr
oduc
tion:
exam
ples
of i
nter
play
of i
nter
actio
ns a
nd in
terfe
renc
eW
e ne
ed a
tool
th
e C
oulo
mb
bloc
kade
and
how
it c
hang
es
Goa
ls: 1
. Sur
vey
the
exce
llent
phy
sics
in th
e ar
ea o
f CB
2. P
repa
re y
ou to
be
able
to u
se th
is to
ol in
you
r ow
n w
ork
1.B
asic
Cou
lom
b B
lock
ade
•con
duct
ance
thro
ugh
a ne
arly
isol
ated
sys
tem
2.M
esos
copi
c Ef
fect
s in
the
Cou
lom
b B
lock
ade
•flu
ctua
tions
of C
B p
eak
heig
hts
and
spac
ings
3.K
ondo
Effe
ct in
Qua
ntum
Dot
s
OU
TLIN
E
Out
line
-loc
alB
asic
Cou
lom
b B
lock
ade
Com
p. T
ech.
I. O
verv
iew
of t
he p
heno
men
a –
no q
uant
um in
terfe
renc
e ef
fect
s!
II. M
agni
tude
of t
he c
ondu
ctan
ce
a)G
eom
etry
, 1 ju
nctio
n, c
harg
e st
eps
b)2
junc
tions
c)C
harg
e pu
mp
d)N
onlin
ear t
rans
port
e)S
uper
cond
uctin
g gr
ains
a)Th
erm
ally
act
ivat
ed re
gim
e –
rate
equ
atio
nsb)
Inel
astic
cot
unne
ling
c)E
last
ic c
otun
nelin
g
III.
Qua
ntum
fluc
tuat
ion
of th
e ch
arge
on
a gr
ain
Mai
n So
urce
s
Sour
ces
Com
p. T
ech.
•“El
ectro
n Tr
ansp
ort i
n Q
uant
um D
ots”
, L. P
. Kou
wen
hove
n, e
t al.
in
“Mes
osco
pic
Elec
tron
Tran
spor
t” b
y So
hn, K
ouw
enho
ven,
& S
chon
, 199
7.•“
Sing
le E
lect
ron
Phen
omen
a in
Met
allic
Nan
ostru
ctur
es”,
M. H
. Dev
oret
, D. E
stev
e, &
C
. Urb
ina,
in “
Mes
osco
pic
Qua
ntum
Phy
sics
”,A
kker
man
s, et
al.
Les H
ouch
es, 1
997.
•“Lo
w-T
empe
ratu
re T
rans
port
Thro
ugh
a Q
uant
um D
ot”,
L. I
. Gla
zman
& M
.Pus
tilni
k, c
ond-
mat
/05
•“Sp
ectro
scop
y of
Dis
cret
e En
ergy
Lev
els i
n U
ltras
mal
l Met
allic
Gra
ins”
, J. v
on D
elft
and
D. C
. Ral
ph, P
hys.
Rep
. 345
, 61-
173
(200
1).
•“Fe
w-e
lect
ron
Qua
ntum
Dot
s”, L
. P. K
ouw
enho
ven,
D. G
. Aus
ting,
and
S. T
aruc
ha,
Rep
. Pro
g. P
hys.
64, 7
01-7
36 (2
001)
.•“
Mes
osco
pic
Fluc
tuat
ions
of C
otun
nelin
g an
d K
ondo
Eff
ect i
n Q
uant
um D
ots”
, L.
I. G
lazm
an, i
n N
ATO
ASI
boo
k ed
ited
by K
ulik
, et a
l., 2
001.
•“Q
uant
um S
mea
ring
of th
e C
oulo
mb
Blo
ckad
e”, K
. A. M
atve
ev, i
n N
ATO
ASI
boo
k ed
ited
byK
ulik
, et a
l., 2
001.
•“Th
e St
atis
tical
The
ory
of Q
uant
um D
ots”
, Y. A
lhas
sid,
Rev
Mod
Phy
s. 72
, 895
-968
(200
0)•“
Theo
ry o
f Cou
lom
b-B
lock
ade
Osc
illat
ions
in th
e C
ondu
ctan
ce o
f a Q
uant
um D
ot”,
C
. W. J
. Bee
nakk
er, P
RB
44,
164
6 (1
991)
.•“
Qua
ntum
Eff
ects
in th
e C
oulo
mb
Blo
ckad
e”, I
. L. A
lein
er, P
. W. B
rouw
er, a
nd
L. I.
Gla
zman
, Phy
s. R
ep. 3
58, 3
09-4
40 (2
002)
.•M
esos
copi
c ef
fect
s in
the
Cou
lom
b B
lock
ade,
G. U
saj,
D. U
llmo,
HU
B;
Phys
. Rev
. B 6
4, 2
0131
9(R
); 64
, 245
324;
66,
155
333;
67,
121
308(
R) (
2001
-200
3).
•“Se
mic
lass
ical
Den
sity
Fun
ctio
nal T
heor
y: S
trutin
sky…
”, D
. Ullm
o &
HU
B, P
RB
63,
125
339
(01)
.
Geo
met
ry a
nd C
harg
ing
Geo
met
ry
Com
p. T
ech.
2ne
utra
l
2
)(
2Q
QCe
E−
=
eU
CQ
/g
neut
ral=
1-ju
nctio
n gr
ain
Isla
nd w
ith 1
junc
tion
Com
p. T
ech.
Gra
in c
onne
cted
to o
ne tu
nnel
junc
tion
and
one
“gat
e” c
apac
itor
Ave
rage
cha
rge
incr
ease
s in
st
eps
as a
func
tion
of v
olta
ge
appl
ied
to th
e ca
paci
tor
How
acc
urat
ely
is th
e ch
arge
qu
antiz
ed?
Is c
ondu
ctio
n th
roug
h th
e gr
ain
poss
ible
?
[Fro
m D
evor
et, E
stev
e, &
Urb
ina,
95]
2 ju
nctio
ns (1
)2
Junc
tions
: Con
duct
ion!
Com
p. T
ech.
V d
rives
cur
rent
U s
ets
the
neut
ralit
y po
int
(gat
e vo
ltage
)
Set
U s
o th
at s
tate
s (1
) and
(0)
have
the
sam
e en
ergy
cu
rrent
flow
s!
[Fro
m D
evor
et, E
stev
e, &
Urb
ina,
95]
Con
duct
ion
Thro
ugh
a C
B Is
land
(con
tinue
d)
2 ju
nctio
ns (2
)
Com
p. T
ech.
2ne
utra
l
2
)(
2Q
QCe
E−
=
•wea
kly
coup
led
lead
s: Q
jum
ps sh
arpl
y•Q
jum
ps a
nd G
has p
eak
whe
n:
Sem
icon
duct
or C
oulo
mb
Blo
ckad
e St
ruct
ures
Dat
a 1-
sc st
ruct
Com
p. T
ech.
Dat
a: L
ater
al Q
uant
um D
ot
Dat
a 2
-lat
eral
Com
p. T
ech. [C
. Mar
cus g
roup
, Har
vard
]
Dat
a: V
ertic
al Q
uant
um D
ot
Dat
a 3
-ver
tical
[Tar
ucha
& K
ouw
enho
ven
grou
ps, N
TT &
Del
ft]
Tran
sfer
ring
Elec
tron
s 1-
by-1
: A P
ump
Cha
rge
pum
p
Com
p. T
ech.
2 is
land
s (3
junc
tions
) req
uire
d:Tr
ansf
er s
eque
nce:
Rel
atio
n of
cha
rge
stat
es fo
r re
gula
r con
duct
ion
[Fro
m D
evor
et, E
stev
e, &
Urb
ina,
95]
Cha
rge
Pum
ping
: Dat
a
Pum
p da
ta
Com
p. T
ech.
[Sac
lay
grou
p]
Plat
eau
trans
ferri
ng e
lect
rons
1-b
y-1
Not
e lin
ear d
epen
denc
e of
pla
teau
cur
rent
on
frequ
ency
!
True
pum
ping
at V
=0C
urre
nt w
ith n
o dr
ivin
g vo
ltage
(but
mod
ulat
ion
volta
ges
doin
g w
ork…
)[F
rom
Dev
oret
, Est
eve,
& U
rbin
a, 9
5]
Cou
lom
b B
lock
ade:
Non
-line
ar T
rans
port
Non
-line
ar: s
chem
.A
pplie
d so
urce
-dra
in
volta
ge o
verc
omes
ch
argi
ng e
nerg
ycu
rrent
Com
p. T
ech.
(a) G
rain
in w
hich
R1,
C1
dom
inat
e. N
ote
step
s in
Ias
mor
e el
ectro
ns c
an b
e lo
caliz
ed o
n th
e gr
ain.
Cou
lom
b St
airc
ase
(b) G
ranu
lar f
ilm –
man
y gr
ains
with
ave
rage
C a
nd R
Firs
t obs
erva
tions
and
dis
ucss
ion
of C
B in
50’
s an
d 60
’s (G
iave
r & J
akle
vic)
[Fro
m G
lazm
an, 0
0]
Non
-line
ar C
B: D
ata
in m
etal
gra
in
Non
-lin:
met
al
Com
p. T
ech.
[D. R
alph
, et a
l. ’9
7]
Cha
ract
eris
tic d
iam
ond-
shap
ed re
gion
of C
B
Non
-line
ar C
B: D
ata
in s
emic
ondu
ctor
qua
ntum
dot
Non
-lin:
sem
ic.
Com
p. T
ech.dI/d
V p
lotte
d vs
. Vg
and
Vsd
[Tar
ucha
and
Kou
wen
hove
n gr
oups
, ‘01
]
Supe
rcon
duct
ing
Gra
in: R
ole
of th
e G
ap
Supe
rcon
d: sc
hem
.
Com
p. T
ech.
Sup
erco
nduc
tivity
rem
inde
rs:
•BC
S g
roun
d st
ate:
ele
ctro
ns p
aire
din
sin
glet
s•I
f the
re a
re a
n od
d nu
mbe
r of
elec
trons
ther
e m
ust b
e at
leas
ton
e qu
asi-p
artic
le o
utsi
de th
e co
nden
sate
•The
min
imum
ene
rgy
for c
reat
ing
aqu
asi-p
artic
le is
the
gap,
∆•∆
can
be
chan
ged
with
by
appl
ying
a m
agne
tic fi
eld
For N
odd
, one
mus
t add
∆
to th
e C
B e
nerg
y pa
rabo
lapa
ss d
irect
ly fr
om
N to
N+2
(fo
r N e
ven
and ∆
>Ec)
[Fro
m D
evor
et, E
stev
e, &
Urb
ina,
95]
Cha
rge
in a
Sup
erco
nduc
ting
Gra
in
Supe
rcon
d: d
ata
Com
p. T
ech.
3rdca
se: ∆
< E
c
N(U
) mea
sure
d w
ith a
CB
ele
ctro
met
er
for d
iffer
ent m
agne
tic fi
elds
--B
eaut
iful v
erifi
catio
n th
at s
uper
cond
ucto
rs re
ally
are
in a
com
plet
ely
paire
d st
ate
–a
mac
rosc
opic
sin
glet
.--
Can
tell
the
parit
y of
a m
etal
gra
in c
onta
inin
g 10
12el
ectro
ns!
[Fro
m D
evor
et, E
stev
e, &
Urb
ina,
95]
A M
odel
Dot
Mod
el H
amTi
me
to b
ecom
e qu
antit
ativ
e!! s
o w
e ne
ed a
mod
el…
Com
p. T
ech.
nla
bels
stat
es in
the
dot (
disc
rete
)k
labe
ls st
ates
in th
e le
ads (
cont
inuo
us)
α=
L, R
(ie
. Lef
t or R
ight
)sl
abel
s spi
n
is a
n op
erat
or
t αn
is in
depe
nden
t of k
–
poin
t con
tact
geo
met
ry
Wha
t is
the
Mag
nitu
de o
f the
Con
duct
ance
?
Mag
G 1
Com
p. T
ech.
Sta
rt at
hig
h T
and
cons
ider
su
r-T
regi
mes
.cc
essi
vely
low
e
∞≡
+=
GG
GG
GG
RL
RL
Hig
hest
T:
CET>>
Cha
rgin
g en
ergy
is n
eglig
ible
com
pare
d to
ther
mal
exc
itatio
ndi
scre
tene
ss o
f ele
ctro
n ch
arge
irre
leva
ntA
dd re
sist
ance
of t
he
two
junc
tions
in s
erie
s:
CET
1stIn
term
edia
te re
gim
e:
≤≈
In a
dditi
on, a
ssum
e:1.
No
quan
tum
mec
hani
cal i
nter
fere
nce
effe
cts
2.R
apid
ther
mal
izat
ion
of e
lect
rons
in th
e do
t –in
cohe
rent
trans
port
(ie. i
nela
stic
rela
xatio
n ra
te >
esc
ape
rate
)3.
Res
ista
nce
of e
ach
junc
tion
is >
e2 /h
Seq
uent
ial t
unne
ling
regi
me,
trea
t with
rate
equ
atio
ns[F
ollo
win
g G
lazm
an`0
0 an
d Pu
stiln
ik&
Gla
zman
`04]
Com
men
ts o
n po
ints
1 a
nd 3
Nee
d G
<e2/
h1.
Neg
lect
qua
ntum
inte
rfere
nce
negl
ect s
ingl
e pa
rticl
e qu
antiz
atio
n(d
iscu
ssed
tom
orro
w!)
T sm
ears
den
sity
of s
tate
s tre
at s
pect
rum
as
cont
inuo
usw
ith D
OS
ν
3. N
eed
for G
L,GR
<< e
2 /h : C
omp.
Tec
h.Tu
nnel
ing
thro
ugh
barr
iers
Qua
ntum
fluc
tuat
ions
of t
he n
umbe
r of e
lect
rons
Sho
uld
be s
mal
l ove
r tim
e of
mea
sure
men
t
RL,
/GC
RCt
==
∆
hG
CC
et
E>
=∆
∆)
/)(
/(
2U
se ti
me-
ener
gyun
certa
inty
rela
tion:
he
G/
2<
Sup
porte
d by
det
aile
d ca
lcul
atio
n as
wel
l…
Rat
e Eq
uatio
ns
Rat
e eq
sFo
r sim
plic
ity, c
onsi
der N
0cl
ose
to th
e de
gene
racy
poi
nt N
0*=1
/2co
nsid
er o
nly
the
char
ge s
tate
s 0
and
1E
lect
rost
atic
ene
rgy
diffe
renc
e:
Cur
rent
from
lead
αin
to th
e do
t via
Fer
mi’s
gol
den
rule
:
Com
p. T
ech.
P i: p
roba
bilit
y fo
r the
dot
to b
e in
cha
rge
stat
e i
f( ε) :
Fer
mi f
unct
ion
(not
per
turb
ed –
rem
embe
r poi
nt 2
abo
ve!)
Con
vert
sum
s to
inte
gral
s ov
er c
ontin
uous
den
sity
of s
tate
s:
2do
t
22
4t
heG
νν
πα
α=
Rat
e Eq
uatio
ns (c
ont.)
Rat
e eq
s (2)
Two
addi
tiona
l con
ditio
ns:
RL
II
−=
11
0=
+P
P
Sol
utio
n yi
elds
for t
he li
near
con
duct
ance
:
Com
p. T
ech.N
ote:
1.A
ll pe
aks
have
sam
e he
ight
!2.
Asy
mpt
ote
0.5
at lo
w
tem
pera
ture
–be
caus
e of
cor
rela
tion
(Can
car
ry o
ut fo
r mut
liple
cha
rge
stat
e an
d no
n-lin
ear b
ehav
ior.)
[Fol
low
ing
Gla
zman
`00,
and
Pus
tilni
k&
Gla
zman
`04]
Bey
ond
Firs
t Ord
er: I
nela
stic
Cot
unne
ling
Inel
astic
cot
unn
Abo
ve: l
owes
t ord
er in
|t|2 ,
invo
lved
tunn
elin
g vi
a a
real
sta
tein
the
dot
Res
ult:
expo
nent
ial s
upre
ssio
n of
Gin
the
CB
val
ley
beca
use
prob
abili
ty
of a
ther
mal
fluc
tuat
ion
to a
llow
occ
upan
cy is
tiny
, exp
(-E C
/T)
But
, hav
e to
con
side
r hig
her-
orde
r act
ivat
ionl
ess
proc
esse
stu
nnel
ing
via
virt
ual s
tate
sin
the
dot
Com
p. T
ech.
Initi
al S
tate
Fina
l Sta
te
*Lnt
RmtM
any
proc
esse
s!
[Fol
low
ing
Gla
zman
`00]
Inel
astic
Cot
unne
ling
(con
t.)
Inel
. cot
unn
(2)
Com
p. T
ech.
Fina
l sta
tes
for t
he m
any
proc
esse
s ar
e di
ffere
nt
sum
pro
babi
litie
s!
∑≈
allo
wed
,
2,
2
in|
|m
nm
nR
LA
heG
νν
1.C
onve
rt su
m o
n n,
m to
inte
gral
in
trodu
ces ν d
ot2
GLG
R
2.H
ow m
any
pairs
of s
tate
s in
the
dot c
ontri
bute
??P
hase
spa
ce a
rgum
ent f
amili
ar fr
om F
erm
i liq
uid
theo
ry:
Inco
min
g en
ergy
is ~
TTh
ere
are
~T 2
way
s to
div
ide
that
ene
rgy
amon
g th
e do
t sta
tes
By
com
parin
g w
ith a
bove
, ine
last
ic c
otun
nelin
g do
min
ates
ther
mal
ly a
ctiv
ated
tra
nspo
rt w
hen
2
/32
2in
⎟⎟ ⎠⎞⎜⎜ ⎝⎛
=C
RL
ETh
eG
GG
[Fol
low
ing
Gla
zman
`00]
Elas
tic C
otun
nelin
g
Elas
tic c
otun
n
Com
p. T
ech.
Wha
t if t
empe
ratu
re is
real
ly v
ery
smal
l, ie
. ver
y fe
w in
elas
tic p
roce
sses
?C
onsi
der e
last
ic p
roce
sses
:E
lect
ron-
like
Hol
e-lik
e
*Lnt
RntFi
nal s
tate
s fo
r the
man
y pr
oces
ses
are
the
sam
e su
m a
mpl
itude
s!
Not
e: e
lect
ron-
like
and
hole
-like
pr
oces
ses
have
diff
eren
t sig
n
[Fol
low
ing
Gla
zman
`00,
and
Pus
tilni
k&
Gla
zman
`04]
Elas
tic C
otun
nelin
g (c
ont.)
Elas
. cot
unn
(2)2 |
|)
(si
gn*
2
el∑
+≈
nn
C
nRn
LnR
LE
tt
heG
εεν
ν
1.K
eep
only
term
s in
whi
ch p
hase
can
cels
exa
ctly
(ie. d
iago
nal a
ppro
xim
atio
n –
we’
ll co
me
back
to th
is to
mor
row
!)2.
Den
omin
ator
cut
s of
f sum
whe
n ε n
~EC
Com
p. T
ech.
∑ <C
nE
nC
RnLn
RL
Et
the
G
||,
22
22
in1
~
ε
νν
a)O
ne s
um
only
one
fact
or o
f νdo
tm
ultip
ly b
yν d
ot/ν
doti
n or
der t
o ar
rive
at fo
rm G
LGR
b)N
umbe
r of t
erm
s in
sum
intro
duce
s fa
ctor
of E
C
⎟⎟ ⎠⎞⎜⎜ ⎝⎛
−+
+−
=0
* 0* 0
0do
t2
2el
111
1/
41N
NN
NE
he
GG
GC
RL
νπ
Elas
.cot
unn
(3)
Elas
ticC
otun
nelin
g(c
ont.)
Com
p. T
ech.
Com
pare
mag
nitu
des
of e
last
ic a
nd in
elas
tic c
otun
nelin
g:
Ela
stic
cot
unne
ling
dom
inat
es a
lread
y w
hen
C
C EE
TT
dot
elν
≡<≈
∆≈
CE
We’
ve s
tudi
ed th
ree
regi
mes
of t
rans
port
so fa
r:
whe
re ∆
is th
e si
ngle
-pa
rticl
e le
vel s
paci
ng
CEC
C EE do
tν
Tin
elas
ticco
tunn
elin
gin
val
ley
elas
ticco
tunn
elin
gin
val
ley
sequ
entia
ltu
nnel
ing:
disc
rete
cha
rges
cont
inuo
usflo
w
[Fol
low
ing
Gla
zman
`00,
and
Pus
tilni
k&
Gla
zman
`04]
Qua
ntum
Tun
nelin
g of
the
Cha
rge
Cha
rge
smea
r 1
Com
p. T
ech.
N0
N)
clas
sica
l
quan
tum
Find
us
ing
our m
odel
Ham
.(o
nly
one
lead
now
!)N)
[Fol
low
ing
Mat
veev
`00]
Qu.
Flu
ctua
tions
of C
harg
e: P
ertu
rbat
ion
Theo
ry
Cha
rge
smea
r 2Fi
nd c
ontri
butio
n of
virt
ual e
xcita
tions
into
and
out
of t
he d
otw
ave
func
tion
and
henc
e <N
>.to
the
grou
nd s
tate
1. E
lect
ron
from
ktu
nnel
s to
n, c
ausi
ng N
N+1
)]0()1(
[E
EtA
nk
nk−
−−
=ε
εn
kε
ε<
<0
Com
p. T
ech.
2. E
lect
ron
from
ntu
nnel
s to
k, c
ausi
ng N
N-1 )]0(
)1(
[E
EtA
kn
kn−
−−
−=
εε
kn
εε
<<
0
Con
vert
both
sum
s to
inte
gral
s:
Loga
rithm
ic d
iver
genc
e at
the
char
ge d
egen
erac
y po
int!!
Qua
ntum
Sm
earin
g of
the
Cha
rge
Step
s
Cha
rge
smea
r 3
Com
p. T
ech.
Div
erge
nce
have
to k
eep
mor
e te
rms!
Mat
veev
acc
ompl
ishe
d by
map
ping
ont
o th
eK
ondo
pro
blem
:
pseu
dosp
infli
ps th
roug
h in
tera
ctio
n w
ith re
serv
oir
real
spi
n st
ill p
rese
nt
2 ch
anne
l Kon
do
char
ge s
tate
0
spin
dow
nch
arge
sta
te 1
sp
in u
p
[Fol
low
ing
Mat
veev
`00]
OU
TLIN
E
Out
line
-loc
alB
asic
Cou
lom
b B
lock
ade
Com
p. T
ech.
I. O
verv
iew
of t
he p
heno
men
a –
no q
uant
um in
terfe
renc
e ef
fect
s!
II. M
agni
tude
of t
he c
ondu
ctan
ce
a)G
eom
etry
, 1 ju
nctio
n, c
harg
e st
eps
b)2
junc
tions
c)C
harg
e pu
mp
d)N
onlin
ear t
rans
port
e)S
uper
cond
uctin
g gr
ains
a)Th
erm
ally
act
ivat
ed re
gim
e –
rate
equ
atio
nsb)
Inel
astic
cot
unne
ling
c)E
last
ic c
otun
nelin
g
III.
Qua
ntum
fluc
tuat
ion
of th
e ch
arge
on
a gr
ain
THE
END
Title
Tem
plat
e
Com
p. T
ech.