相関量子系のダイナミクス: 電子系と large n超対...

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相関量子系のダイナミクス: 電子系と large N超対称QCDの比較 Takashi Oka (U-Tokyo) K. Hashimoto (RIKEN iTHES, Osaka-U) A. Sonoda (Osaka-U), N. Iizuka (RIKEN) string theory/ hadron physics correlated electron system N. Tsuji (Tokyo-U) P. Werner (Fribourg) M. Eckstein (Humburg) quantum spin S. Takayoshi (NIMS) M. Sato (Aoyama) topological system T. Kitagawa (Rakuten) T. Mikami (U-Tokyo) Gauge/gravity duality Hashimoto Iizuka Oka PRD ‘11 Hashimoto Oka JHEP ‘13 Bethe ansatz: Oka PRB `12 Numerical: Oka ‘03~, Aoki Tsuji, .. RMP `14 to appear Planckian thermalization (scale invariant sys.) thermalization v.s. hydrodynamic regime

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Page 1: 相関量子系のダイナミクス: 電子系と large N超対 …881791/spm/2014/slides/Oka.pdf相関量子系のダイナミクス: 電子系と large N超対称QCDの比較

相関量子系のダイナミクス: 電子系と large N超対称QCDの比較

Takashi Oka (U-Tokyo)

K. Hashimoto (RIKEN iTHES, Osaka-U) A. Sonoda (Osaka-U), N. Iizuka (RIKEN)

string theory/ hadron physics correlated electron system

N. Tsuji (Tokyo-U) P. Werner (Fribourg) M. Eckstein (Humburg)

quantum spin

S. Takayoshi (NIMS) M. Sato (Aoyama)

topological system

T. Kitagawa (Rakuten) T. Mikami (U-Tokyo)

Gauge/gravity duality Hashimoto Iizuka Oka PRD ‘11 Hashimoto Oka JHEP ‘13 Bethe ansatz: Oka PRB `12

Numerical: Oka ‘03~, Aoki Tsuji, .. RMP `14 to appear Planckian thermalization (scale invariant sys.)

thermalization v.s. hydrodynamic regime

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Strong field physics in Condensed matter and Nuclear physics

hole density

T

superconductor

phase diagram of hadron (Fukushima-Hatsuda)

phase diagram of Hi Tc

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Strong field physics in Condensed matter and Nuclear physics

ion collision pump probe exp.

Hirori, Tanaka et al. Nat. Com. 2011

THz laser pulses strong E and B fields

Takashi Oka

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Strong field physics in Condensed matter and Nuclear physics

Interesting problems

Excitation

Relaxation

Above threshold: fast thermalization

hydrodynamic system

• Schwinger mechanism (quark-antiquark pair production) • Deconfinement transition of gluons

Quark gluon plasma (QGP) Laser induced metallization

Gapped: exponentionally slow relaxation

• doublon-hole production • lattice distortion/phonon oscillation

Gapless: fast relaxation

“temperature”, “current”,… Wi: parameters

(coupling const., temperature,..)

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Aoki, Tsuji, Eckstein, Kollar, Oka, Werner RMP to appear

「強相関系の非平衡物理」日本物理学会誌,2012年4月号

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Difference Movie

Wang et al. … N. Gedik Phys. Rev. Lett. 109, 127401 (2012)

I(E, kx, ky, t<0)

data from N. Gedik (MIT)

Pump-probe technique

Time resolved ARPES (angle resolved photo emission spectroscopy)

Gedik@MIT group

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Wang et al. … Science ‘13

Floquet state = electron + n-photon

Topology can be changed! Oka Aoki ‘09

coherent regime

Aoki, Tsuji, Eckstein, Kollar, Oka, Werner RMP to appear

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Aoki, Tsuji, Eckstein, Kollar, Oka, Werner RMP to appear

Bi2SrCaCu2O8+d

effective temperature

fermion distribution

fit with Fermi-function

w

Perfetti et al. PRL ‘07

Hi Tc cuprate

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Aoki, Tsuji, Eckstein, Kollar, Oka, Werner RMP to appear

2D gapless Dirac

Wang et al. Gedik group PRL 2012

Fermi energy

Dirac cone

bulk band

Polynomial relaxation

*2D Dirac has no other E-scale

*ちなみに理論は分かっていない

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Aoki, Tsuji, Eckstein, Kollar, Oka, Werner RMP to appear

Mott insulator cold atom (Esslinger group ‘11) solid state (Iwai et al. ‘03)

Exponential relaxation

Theory:

Sensarma et al., Eckstein et al., Tsuji et al. (SC phase)

prethermalization

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Aoki, Tsuji, Eckstein, Kollar, Oka, Werner RMP to appear

Big challenge

Is a transient ordered phase possible?

Ferromagnet Yes (exp: Takubo et al. PRL ’05)

Must redo the theory of phase transitions

transient SC (Tsuji et al. PRL ’13)

RG, fixed point,…

Haldane-AKLT phase (Takayoshi-Sato-Oka ‘14)

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Classic case

Quench problem

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Classic case

Quench problem

fluctuation growth

Production rate of B

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Quantum case

slow Quench problem

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Quantum case

Quench problem

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Quantum case

Quench problem

distribution ~ “thermal state”?

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Examples

insulator

A B excitation

Noneq. steady state in E-field (if exists)

charge pair

normal superfluid (broken U(1))

vortex

Schwinger mechanism (Zener breakdown)

Kibble-Zurek

….

Haldane-AKLT state (Symmetry protected topological state)

spin polarized state Takayoshi-Aoki-Oka ‘13 Takayoshi-Sato-Oka ‘14

?

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production rate

vacuum decay rate/ Euler-Heisenberg Lagrangian

f

two level approximation

(fidelity, Loschmidt echo)

① Full dynamics

Quantum walk in energy space

Oka, Konno, Aoki: PRL (2005)

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Hubbard model (closed ring)

Schwinger mechanism (Zener breakdown)

Large N SUSY QCD

(1dim) Oka Aoki: PRL (2003), PRL(2005) (DMFT) Eckstein, Oka, Werner: PRL (2010)

(Bethe) Oka Aoki, 2010, Oka 2012

transient steady state

production rate of charge pairs

QED

Euler Heisenberg 1936, Schwinger 1951

semiconductor

Zener 1932

production rate of charge pairs

steady state Karch O’Bannon (2007)

(large gluon bath)

Semenoff-Zarembo 2011

vacuum decay rate/ Euler-Heisenberg Lagrangian

interacting model in E-field

vacuum decay rate

(1dim dmrg) Oka Aoki: PRL(2005) Hashimoto Oka 2013

Nakamura 2010, Karch Sondhi (2011)

+ dynamics

“Exact Nonequilibrium Steady State of an Open Hubbard Chain”

(MPS + Liouville) Prosen PRL 2014

Brezin Itzykson 1970, Popov 1970

② ①

② ③

(Quantum Walk) Oka, Konno, Aoki: PRL (2005)

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``Consequences of Dirac‘s Theory of Positrons“ (English translation in arXiv)

W. Heisenberg and H. Euler, Z. Physik 98, 714 (1936) also Weisskopf (1936)

effective Lagrangian

Euler-Heisenberg effective Lagrangian

(1909–1941)

W. Heisenberg H. Euler

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Dirac fermion

W. Heisenberg and H. Euler, Z. Physik 98, 714 (1936)

imaginary part = electron-positron pair production rate

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Cross correlation in nonlinear optics

In Lorentz invariant material

¥

Cotton Mouton effect (birefringence induced by B)

Kerr effect

Dirac fermions show nontrivial nonlinear ME effect

Lorentz invariants

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Relation to the Berry phase theory of polarization

EH effective Lagrangian

Berry phase theory of polarization (Resta’s twist operator version)

TO Aoki PRL ‘05

Resta (late 80s) ‘92, King-Smith Vanderbilt ’93, .. Resta PRL 99

adiabatic limit (small E, long time)

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Dielectric breakdown in Mott insulators (1dim) TO, Aoki: PRL (2003), PRL(2005) (DMFT) Eckstein, TO, Werner: PRL (2010)

electric field F

half-filled Hubbard model (1-dim)

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(1dim) TO, Aoki: PRL (2003), PRL(2005),.. (DMFT) Eckstein, TO, Werner: PRL (2010)

electric field F

half-filled Hubbard model (1-dim)

Doublon-hole pair

Dielectric breakdown in Mott insulators

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Nonequilibrium DMFT

threshold form

Eckstein, TO, Werner PRL 2010 Eckstein, Werner PRB 2012

transient steady state

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How do we solve this analytically?

Hubbard model is exactly solvable but one cannot obtain the matrix elements

ignore 2 pairs, 3 pairs, .., magnon

production rate

f

two level approximation

1 pair

g.s.

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1. Use complex time

Dykhne JETP (1962), Daviis, Pechukas, J.Chem.Phys. (1976)

Imaginary time method (Landau-Dykhne theory)

2. Find the singular point

3. Tunneling probability

imaginary part of the dynamical phase

Landau-Lifshitz Quantum mechanics

Generalized Landau-Zener formula

Matrix version of WKB approximation

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U=8

Oka PRB 2012

Momentum resolved dh-pair creation rate

complex momentum (~WKB) electric field

DC, AC, pulse

DE: d-h energy, G: complex path, F: Jacobian

Imaginary time method + Bethe ansatz

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1D Mott insulator

DC-limit

Estimate for 1d Mott insulators

No p-dependence

Oka-Aoki 2010

x: dh-pair size (correlation length) ~1,2sites

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Keldysh parameter

AC-field: Keldysh crossover

mulit-photon

tunneling

Weak field:multi-photon Strong field: q-tunneling

~ nonlinear transport ~ femto-second pump-probe

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Hubbard model (closed ring)

Schwinger mechanism (Zener breakdown)

Large N SUSY QCD

(1dim) Oka Aoki: PRL (2003), PRL(2005) (DMFT) Eckstein, Oka, Werner: PRL (2010)

(Bethe) Oka Aoki, 2010, Oka 2012

transient steady state

production rate of charge pairs

QED

Euler Heisenberg 1936, Schwinger 1951

semiconductor

Zener 1932

production rate of charge pairs

steady state Karch O’Bannon (2007)

(large gluon bath)

Semenoff-Zarembo 2011

vacuum decay rate/ Euler-Heisenberg Lagrangian

interacting model in E-field

vacuum decay rate

(1dim dmrg) Oka Aoki: PRL(2005) Hashimoto Oka 2013

Nakamura 2010, Karch Sondhi (2011)

+ dynamics

“Exact Nonequilibrium Steady State of an Open Hubbard Chain”

(MPS + Liouville) Prosen PRL 2014

Brezin Itzykson 1970, Popov 1970

② ①

② ③

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Gauge/gravity duality using the D3/D7 configuration

review: Erdmenger et al. 0711.4467

Kim et al. 1205.4852

probe D-brane

D-brane

gluon

quark

= low energy theory of the D3/D7 configuration

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SUSY Yang Mills: Maldecena ’99

SYM+quark: Karch Katz ’02

Sakai Sugimoto ‘04

review: Erdmenger et al. 0711.4467

Kim et al. 1205.4852

Classical field theory described by the Dirac-Born-Infeld (DBI) action

“nonlinear Maxwell equation + AdS metric”

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Gauge/gravity correspondence

Gubser, Klebanov, Polyakov ’98, Witten ‘98

on shell is the solution of the equation of motion

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GKP ’98, Witten ‘98

We want the following

Euler-Heisenberg Lagrangian from Gauge / Gravity correspondence

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GKP ’98, Witten ‘98

Euler-Heisenberg Lagrangian from Gauge / Gravity correspondence

We want the following

Hashimoto Oka JHEP `13

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Euler-Heisenberg Lagrangian of the N=2 SUSY QCD in the large Nc limit

Hashimoto Oka JHEP `13, Hashimoto Sonoda Oka in prep.

Example: Kerr/Cotton Mouton effects

gap

Kishida et al. Nature 2000

1D Mott insulator

1D band insulator

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Time dependent calculation in the gapless case

solve EOM

polarization current

steady state

current in the Hubbard model

Eckstein TO Werner PRL ‘10

polarization current

Hashimoto TO JHEP ‘13

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40

Time dependent calculation in the gapless case

solve EOM

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Horizon formation and the effective Hawking temperature

cf) Formation of black hole and horizon

Hashimoto TO JHEP ‘13

boundary AdS direction

arrows = -z direction light cone

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Hashimoto Oka JHEP ‘13

Effective temperature

Time evolution of the Hawking temperature

dissipation source = gluons

universal scaling plot

Planckian thermalization

(This can be obtained simply by dimensional analysis)

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Wang et al. Gedik group PRL 2012

dissipation source = acoustic phonons?

Effective temperature

Comparison with experiment??

dissipation source = gluons

laser induced temperature ~ 100-1000K

Might explain the ultrafast ``thermalization” (good fit to the Fermi-function)

Hashimoto Oka JHEP ‘13

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Summary and perspectives

Universal relations

1. Nonlinear optical response in QCD (confinement phase)

2. Planckian thermalization

“Fast thermalization puzzle” in QGP formation

= QGP is described by a low viscosity fluid from a very fast time scale = very very fast thermalization

Strong E and B fields at ion collision

..consistent with experiment

(Note: Our theory do not describe the Yang-Mills thermalization)

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Dirac model = Landau-Zener model

DC field

singular point

k integral

Schwinger Phys. Rev.82, (1951)

Heisenberg-Euler (1936)

3+1 Dirac system

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Keldysh crossover and the creation rate

Weak field:multi-photon Strong field: q-tunneling

~ nonlinear transport ~ femto-second pump-probe

T=infinite state

produced carriers do not contribute to transport

In realistic systems, these excitations should cooled down

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Comparison with numerical result (1d Hubbard)

pulse fields

(td-DMRG)

(Bethe ansatz)

doublon density

doublon density

production rate

Landau-Dyhkne formula ignores quantum interefrence in multi-tunneling events (Stokes phenomena)

deviation at large F

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49

Comparison with numerical results (AC-field)

doublon density

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[Brower,Mathur,Tan (03)]

Lattice

[Morningstar,Peardon (99)]

Superstring

Superstring: better than simulations? 3-2

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Superstring Experiment

Lattice

[Sakai,Sugimoto,KH (0806.3122)]

(0.74 fm)2

0 0.54 fm

2.2 – 1.3 0.73 7.5 5.8 4.4 2.3

0.20 –1.9

(0.875 fm)2

– 0.116 fm2

0.674 fm 2.79

–1.91 1.27 13.2

4.2 – 6.5 3.7 – 7.5

– – –

4.99 2.49 0.06

–2.45

Radii of proton/neutron

Superstring: better than simulations? 3-3

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10 15 20 25 30

0.004

0.002

0.002

0.004

0.006

0.008

0.010

(Inter-nucleon distance)

[Sakai,Sugimoto,KH (0901.4449)]

[Aoki,Ishii,Hatsuda (‘07)]

Lattice QCD simulations :

Experiments:

[Stoks,Klomp,Terheggen,deSwart (‘94)]

Superstring:

Superstring: better than simulations? 3-4

Nuclear forces