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Anderson Anderson LocalizationLocalization19581958--20082008
FromFrom electronselectrons, , towardstowards ultrasoundultrasoundand and …… cold cold atomsatoms
Bart van TiggelenBart van TiggelenLaboratoire de Physique et ModLaboratoire de Physique et Modéélisation des Milieux lisation des Milieux
CondensCondensééssUniversitUniversitéé Joseph Fourier /CNRSJoseph Fourier /CNRS
ScatteringScattering Systems Systems withwith complexcomplex Dynamics FOR760 2008: Dynamics FOR760 2008: OctoberOctober 6 20086 2008
Localization [..] very few believed it at the time, and even fewer saw itsimportance, among those who failed was certainly its author.
It has yet to receive adequate mathematical treatment, and one has to resort to the indignity of numerical simulations to settle even the simplest questions about it.
P.W. Anderson, Nobel lecture, 1977
1958 Anderson « vanishing of diffusion »
1960 Mott/Ioffe-Regel
1965 Mott Minimum conductivityVariable range hopping
1972 Thouless Sensitivity to BC: g < 1(Thouless criterion)
>1982 Sharvin, Lagendijk,Maret, Maynard,…
Weak localizationMesoscopic physics!
1977 Anderson/Mott Nobel Prize
1980 « gang of four » Scaling theory
1980 Götze, Vollhardt, Wölfle Self-consistent theory
1982 Halperin, Pruisken Scaling theory of Quantum Hall effect
πλ2≤l
)log()(log
Lg
∂∂
Half a century…….
1983 Fröhlich & Spencer Mathematical proof for 3D Anderson model
1984 Anderson 25 years localization« unrecognizable monster »
1986 Anderson « Theory of white paint »
1987 Papanicolaou, Sheng Prediction of Localization of Seismic Waves in layered Earth
Crust1987 Souillard Localization of Gravitational Waves
in Universe?
1986 Kramer, Mackinnon, Economou,
Soukoulis, Schreiber
Tight binding model
1990 Dorokhorov, Melloetal, Beenakker
Altschuler
DMPK equation for wire
interactions
1988 John Prediction of Localization of light in Photonic crystals
>1991
Bell-labsWeaverGenack
Exxon (Sheng etal)
2D localization microwaves2D localization of ultrasoundQ1D localization microwaves
2D localization of bending waves>1995 BEC community Localization of light in BEC cold atomes
gazes or the contrary?
2000 GenackBeenakker, …Van Tiggelen/
Lagendijk/Wiersma
Statistics in localized regime (exp)Idem (theo)
D(r) in localized regime
2006 Maret Anomalous dynamic transmission of lightnear mobility edge
2007 Fishman/Segev Transverse Light Localization in 2D lattices
1997 Wiersma, Lagendijk 3D localizationof infrared light
>1998
Cao, Wiersma etal, Soukoulis, Sebbah, …
Random lasering from(pre) localized states
2008 Page/Skipetrov/Van Tiggelen 3D localization of ultrasound
)()(),(),( 2St tStDt rrrr −=∇−∂ δδρρ
tDt
tt 6
),(),(
)(2
2 ==r
rrr
ρ
ρ
Diffusion Diffusion ofof WavesWaves
diffusion constantdiffusion constant
*v31 l=D
Diffusion = Diffusion = randomrandom walkwalk ofof waveswaves
nmmL
73920
==
λμ
Diffusion, works even better than expected!
GaP poreux
transmission
réflexion )1.2(250
/23**
2
==
=
ll knm
smD
1/t3/2
Diffusion equation
Lagendijk etal, PRE 2003
1 µm
Anderson localisation?Anderson localisation?
••suppressedsuppressed diffusion : rdiffusion : r22(t)(t) constant constant «« D(t) ~ 1/tD(t) ~ 1/t »»
••Dense Dense «« pure pointpure point »» spectrumspectrum / / ((nono levellevel repulsionrepulsion: : infiniteinfinite media)media)
••GiantGiant nongaussiannongaussian fluctuations (fluctuations (lognormallognormal))
•• complexcomplex dynamicsdynamics (open media): T(t) (open media): T(t) ~ exp(~ exp(--D(tD(t) t /L) t /L22))((anomalousanomalous leakingleaking))
•• T(L), G(L) T(L), G(L) ~ exp(~ exp(--L/L/ξξ))
Mesurable?
Mesurable?
••NeedNeed goodgood observable observable withwith continuouscontinuous control control parameterparameter: L,t, f, E ..: L,t, f, E ..••NeedNeed a a goodgood theorytheory thatthat allowsallows engineeringengineering
R(t) ~1/tR(t) ~1/t22
«« UnrecognizableUnrecognizable monstermonster »»
Trivial Localization: tunnelling is inefficient
r
1D 1D mattermatter wavewave
m
Localisation is «not trivial yet reasonable »
r
1D 1D mattermatter wavewave
m
V(r)
Localisation is « non trivial »: phase!
r
0),(),()( 22 =∇−∂ ttt rrr ψψε
⎪⎩
⎪⎨⎧
=
−=⇒−=
2
2)](1[)()exp()(
ω
ωεωψψ
EV
tirr
r VE >
ClassicalClassicalwaveswaves
m
r
MobilityMobilityedgeedge
k(E)k(E)ℓℓ(E)=1(E)=1
3D: 3D: strongstrong disorderdisorderExtendedExtended statesstates
LocalizedLocalized statesstates
m
Distribution of leakage ratesN dipoles in a 3D sphere
Kottos & Weiss 2003; Pinheiro/van Tiggelen PRE 2004
Γ-1
13 =ρλ
603=ρλ
P(Γ)
Leakage rate/ Thouless frequency
Γ∝Γ
1)(P
LocalizationLocalization in open mediain open media
1>>lk *ΨΨ
*31 lEB vD =
1≈lk
( )ωπ NvC
DD EB
),(11 rr+=
Ψ
*Ψ
VollhardtVollhardt & & WWöölflelfle, 1980, 1980
SchwarzshildSchwarzshild//MilneMilne , 1900, 1900Chandrasekhar, 1950Chandrasekhar, 1950
Van de Van de HulstHulst, 1950, 1950
TheoreticalTheoretical DescriptionDescription
Boltzmann equation
Self consistent theory
( ) ( )
( ) ( )ωπ
δπ
NvG
DD
GD
EB
),(11
'4'),(
rrr
rrrrr
+=
−=∇⋅∇−l
reciprocityreciprocity ),(),( rrrr GC =⇒
==
( ) ⎟⎟⎠
⎞⎜⎜⎝
⎛−=⇒
==−= ∫ <
2
2/13
11
14)0(),(');('),(
l
l l
kDD
DqdGGGG
B
qqrrrrrr π
3D 3D unboundedunbounded mediummedium
OK OK MottMott
QuasiQuasi--1D 1D halfhalf--wirewirezz
( )
)(
2exp)(211:
4),('4'),()(2
l
ll
N
zDzDDDdz
d
GGzDdzd
BB
∝
⎟⎠⎞
⎜⎝⎛−=⇒+==⇒
=⇒−=∂−⇒≡
ξ
ξτξτ
τπττττδπτττ τ
OK DMPKOK DMPK
NN
ComplexComplex DynamicsDynamics in in finitefinite open mediaopen mediaSkipetrovSkipetrov & Van Tiggelen, PRL 2004,2005& Van Tiggelen, PRL 2004,2005
),,,(21),(
12 qzzG
kDzD B l+=
ssq2
3/
dq∫< l
)'(),,',(),,',(),(),,',( 2 zzqzzGqqzzGzDqzzG z −=+∂+− δss ss ss ss ss
ss
Diffuse Diffuse regimeregime: simple : simple polespoles LocalizedLocalized regimeregime: Riemann : Riemann sheetssheets
ΩΩ
ss
ΩΩ
ss
I(I(ΩΩ))
P(s)P(s)
ComplexComplex FrequencyFrequency ΩΩ++isis
( )stszzGdstT s −∝ ∫∞
exp),,()(0
tt--3/23/2
tt--22
time/(time/(ζζ2 /2 /DDBB))
R(t)R(t)
3D, 3D, localizedlocalized HalfHalf spacespace : k: kℓℓ=0.7=0.7
zz
1D sismologie : 1D sismologie : ShengSheng PapanicolaouPapanicolaou, 1987, 1987Q1D (DMKP) Q1D (DMKP) TitovTitov, , BeenakkerBeenakker, 2000, 2000
2
1)(t
tR ∝
3D Transverse localisation 3D Transverse localisation ofof ultrasoundultrasoundPage (Winnipeg), Page (Winnipeg), SkipetrovSkipetrov, Van Tiggelen, , Van Tiggelen, CherroretCherroret
diffuse localized
10 mm
8 – 23 mm
Diffuse: <ρ2> = 4Dttransition: <ρ2>~ L2, not t2/3
Localized: <ρ2>~ Lξ
3D Transverse localisation 3D Transverse localisation ofof ultrasoundultrasoundPage (Winnipeg), Page (Winnipeg), SkipetrovSkipetrov, Van Tiggelen, , Van Tiggelen, CherroretCherroret
ρ
L=15 mm
3D Transverse localisation 3D Transverse localisation ofof ultrasoundultrasoundPage , Page , SkipetrovSkipetrov, Van Tiggelen, , Van Tiggelen,
Nature Nature PhysicsPhysics OctoberOctober 20082008
Time (ms)
ρ = 15 mmρ = 20 mmρ = 25 mmρ = 30 mm4 D0t
kℓ ≈ 1,82vE=17,4 km/s=3.5 vp
ξ= 16,3 mm
Transversesize
Transverse position
Near fieldUltrasound
energy
TimeTime--dependentdependent transmissiontransmission
T(t))(tδ
SpeckleSpeckle distribution of transmissiondistribution of transmission
Rayleigh Random matrixg=0.8 +/- 0.02
Inhibition of transport of Q1D BEC in Inhibition of transport of Q1D BEC in randomrandom potentialpotential
Orsay group, Firenze groupOrsay group, Firenze groupPRL PRL octoct 20052005
Time after trap extinction
expansion
1<μδV
n(x,t)V(x)
mobility edge
Diffusive regime Localizationwith ξ > ℓ
Localizationwith ξ < ℓ
LocalizationLocalization of of noninteractingnoninteracting cold cold atomsatoms in 3D white noisein 3D white noise
⎟⎟⎠
⎞⎜⎜⎝
⎛−∝=
mkt
2)0,(
22hμθψ k
band edge
TrapTrap stagestage
µchemical potential
2)(rψ
expansion stage (t=0)expansion stage (t=0)
gVet ti )(),( rr −
= − μψ μ
∞→
==
tttn ??),(),( 2rr ψ
RandomRandom potentialpotential
εε ∝)(D
with Sergey Skipetrov, Anna Minguzzi and Boris Shapiro
DensityDensity profile of profile of atomsatoms atat large timeslarge times
),(),()()2(
),( 23
3
tPEAdEdtn E rkkkr ∫∫∞
∞−= φ
π
Distribution of velocitiesmv = ћk
Spectral function
Probability of quantum diffusion
EiUUkE +−−−
4/1Im122π
)'(4)'()( rrrr −= δπUVV
Mean free path: U1
=l 2UE < localized
DensityDensity profile of profile of atomsatoms atat large timeslarge times
Potential fluctuation/chemical potential
FractionOf
Localized atoms
DensityDensity profile of profile of atomsatoms atat large timeslarge times
-2 -1 0 1 2 3 4-17.5
-15
-12.5
-10
-7.5
-5
-2.5
0
),()(),( loc tnntn AD rrr Δ+=
ssADs
trtnD c /1/23
1),()()( −∝Δ⇒−∝ rεεεννεε
εξ /13loc1)(
)(1)( +∝⇒−
∝r
nc
r
localized anomalous diffusion
nloc(r)
Selfconsistent theory (ν=s=1)
50 50 yearsyears of Anderson of Anderson LocalizationLocalizationParis, Institut Henry PoincarParis, Institut Henry Poincaréé
4/5 4/5 decemberdecember 20082008
http://www.andersonlocalization.com
SpeakersSpeakers: P.: P.W.AndersonW.Anderson, D.J. , D.J. ThoulessThoulessA. Aspect, S. John, P. A. Aspect, S. John, P. WWöölflelfle, , G. Maret, R. Weaver, A.Z. G. Maret, R. Weaver, A.Z. GenackGenack, , A. A. LagendijkLagendijk, A. , A. MirlinMirlin, M. Schreiber, M. Schreiber
TheoryTheory and and experimentsexperiments, , oldold and new and new thingsthings
Localized? : kℓ < 4,2 D(t) ~1/t1/3Mobility edge: kℓ ≈ 4,2D(t) ~1/t
G. Maret G. Maret etaletal, EPL 2006, EPL 2006tr
ansm
issi
on
time
TiO2 powder ; L/ℓ =10 000
Sample and CBS
T(t))(tδ
ClichClichéé, clich, clichéé !!LL’’article darticle d’’AndersonAnderson’’s en 1958 a s en 1958 a ééttéé «« oftenoften quotedquoted but but nevernever readread »»Il y a autant de dIl y a autant de dééfinitions et dfinitions et d’’approches quapproches qu’’il y a de publications.il y a de publications.La moitiLa moitiéé des publications est des publications est ……....
•• …….. soit fausse.. soit fausse•• …….. soit triviale .. soit triviale •• …….. soit d.. soit dééjjàà contenue dans le papier dcontenue dans le papier d’’Anderson en 1958 Anderson en 1958 •• …….. soit trop compliqu.. soit trop compliquéée ou trop phe ou trop phéénomnoméénologiquenologique
pour comprendre les exppour comprendre les expéériencesriences
ProtectProtect me me fromfrom knowingknowing whatwhat I I dondon’’tt needneed to knowto knowProtectProtect me me eveneven fromfrom knowingknowing thatthat therethere are are thingsthings to know to know thatthat I I dondon’’tt knowknowProtectProtect fromfrom knowingknowing thatthat I I decideddecided not to know not to know
about the about the thingsthings thatthat I I decideddecided not to know aboutnot to know about
Douglas Adams, Douglas Adams, MostlyMostly HarmlessHarmless, 1992, 1992
Distance in units of mean free pathdistance
density of atoms