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Random first-order transition of a spin glass model in three - - PowerPoint PPT Presentation

Random first-order transition of a spin glass model in three dimensions Toward a mean-field theory for glass transitions Koji Hukushima University of Tokyo, Dep. of Basic Sciences 14 August 2015 In collaboration with Takashi Takahasi.


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Random first-order transition of a spin glass model in three dimensions

– Toward a mean-field theory for glass transitions – Koji Hukushima

University of Tokyo, Dep. of Basic Sciences

14 August 2015 In collaboration with Takashi Takahasi. Japan-France Joint Seminar

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 1 / 30

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Outline

1 Spin glasses and Random First-Order Transition 2 Potts glass model 3 Our numerical results

Thermodynamic properties Phase diagram of ϵ-coupled system Dynamical properties

4 Summary

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 2 / 30

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Spin glasses and Random First-Order Transition

Outline

1 Spin glasses and Random First-Order Transition 2 Potts glass model 3 Our numerical results

Thermodynamic properties Phase diagram of ϵ-coupled system Dynamical properties

4 Summary

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 3 / 30

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Spin glasses and Random First-Order Transition

Order of phase transition

Ehrenhest’s criterion

Phase transition is described by a singularity of free energy. Phase transition with a singularity in nth order differential of free energy is called nth order phase transition.

1st order transition

  • Internal energy, entropy and volume have a jump

at Tc.

  • Order parameter also has a jump.
  • latent heat and delta-function-type divergence in

specific heat.

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 4 / 30

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Spin glasses and Random First-Order Transition

Order of phase transition

Ehrenhest’s criterion

Phase transition is described by a singularity of free energy. Phase transition with a singularity in nth order differential of free energy is called nth order phase transition.

2nd order transition

  • Internal energy, entropy S, order parameter O

change continuously at critical temperature.

  • Specific heat, susceptibility χ follow power-law

divergence at Tc

  • divergence of length scale ξ
  • universality class by critical exponents.

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 4 / 30

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Spin glasses and Random First-Order Transition

1.5 order phase transition?

  • There exists infinite order phase transition like KT transitions.
  • Meanwhile, a kind of phase transitions, not 1st order and not 2nd order,

has attracted much attention...

Random first-order transition (RFOT)

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 5 / 30

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Spin glasses and Random First-Order Transition

RFOT and spin glasses

RFOT has been found in some spin glass models with one-step replica symmetry breaking. Overlap distribution P(q)

1 step RSB

  • p-state Potts glass with p ≥ 4
  • p-spin glass with p > 2

P(q) for full RSB P(q) for 1RSB

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 6 / 30

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Spin glasses and Random First-Order Transition

Some features of a 1RSB transition

Random First-Order Transition (RFOT)

= ⇒ the phenomenology of glass transitions

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 7 / 30

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Spin glasses and Random First-Order Transition

Does RFOT provides a good theory of glass transitions?

Some statistical-mechanical models of RFOT

  • mean-field Potts glass model
  • mean-field p-spin glass model
  • Biroli-M´

ezard model (lattice glass model) on Bethe lattice

  • K-SAT, . . .

They are all mean-field models with 1RSB transition.

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 8 / 30

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Spin glasses and Random First-Order Transition

Does RFOT provides a good theory of glass transitions?

Two difficulties –mean-field theory and quench disorder–

1 One of the next issues to be addressed is to clarify whether predictions

from the mean-field theory survive in finite dimensional models. Today’s issue

2 The correct theory of glass transitions must be free from quench

disorder. Universality class??

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 8 / 30

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Potts glass model

Outline

1 Spin glasses and Random First-Order Transition 2 Potts glass model 3 Our numerical results

Thermodynamic properties Phase diagram of ϵ-coupled system Dynamical properties

4 Summary

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 9 / 30

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Potts glass model

RFOT occurs in a three dimensional Potts glass model?

Potts glass Hamiltonian in three dimensions

HJ(S) = − ∑

(ij)

Jijδ (Si, Sj) , Potts variable: Si = {0, 1, · · · , p−1}

Questions

  • Does the model have a SG phase transition beyond a mean-field

theory? Is it RFOT?

  • Low-temperature properties are described by replica symmetry breaking?
  • Most of researchers believe that dynamical singularity at Td is smeared
  • ut in finite dimensions. Does the singularity completely disappear?

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 10 / 30

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Potts glass model

Summary of the previous numerical studies

3 dimensional Potts glass models

  • No phase transition for p = 3, Scheucher et al(1990).
  • No phase transition for p = 10, Brangian et al(2002).
  • Finite T transition for p = 3, Lee-Katzgraber-Young(2006).
  • Finite T transition for p = 4 JANUS project, Cruz et. al(2009).
  • Finite T transition for p = 5 and 6 JANUS project, Ba˜

nos et. al(2010).

  • It is found that p-state PG model with p = 3, 4, 5 and 6 shows a finite

temperature SG transition by extended-ensemble MC simulations.

  • The transitions are continuous and there is no finite discontinuous jump
  • f the order parameter.
  • No features of RFOT/1RSB were found.

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 11 / 30

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Potts glass model

Comment from Cammarota et al (2013)

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 12 / 30

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Potts glass model

Comment from Cammarota et al (2013)

Detect 1RSB transition/RFOT in finite dimensions,

1 The number of Potts states, p, have to be large enough. 2 A rate of antiferromagnetic coupling have to be increased for preventing

a ferromagnetic ordering.

3 The connectivity must be increased in order to keep the frustration.

(Large p suppresses the frustration in general) Thus, in a naive sense, it is very hard to meet these conditions simultaneously on a three dimensional lattice. It might be possible in higher dimensions like d = 9, 10, ....

Our strategy:

  • we don’t want to go to high dimensions.
  • Instead, interaction range is enlarged up to 1st, 2nd and 3rd neighbors.

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 12 / 30

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Potts glass model

Our Model

7-state Potts glass model

  • 3rd neighbor random interactions with ±J type. (# of neighbors = 26).
  • System sizes: L = 4, . . . , 10 , Number of samples: 256 ∼ 1024.
  • Exchange MC(parallel tempering).
  • 1

1

  • 1

1 2

  • 1

1 2

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 13 / 30

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Our numerical results

Outline

1 Spin glasses and Random First-Order Transition 2 Potts glass model 3 Our numerical results

Thermodynamic properties Phase diagram of ϵ-coupled system Dynamical properties

4 Summary

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 14 / 30

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Our numerical results Thermodynamic properties

MC results for 7-state PG in three dimensions

non-linear susceptibility χSG 5 10 15 20 25 30 35 40 45 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

χSG T/J

Nearest 3rd Nearest

L=4 L=6 L=7 L=8 L=9 L=10 L=4 L=8 L=16

  • 7-state PG model exhibits a

finite temperature SG transition at Tc/J ≃ 0.42.

Finite-size scaling for χSG

0.5 1 1.5 2 2.5 3

  • 10
  • 5

5 10 15 χSG/L1+η/(1+aL-ω) (T-Tc)L1/ν/J L=7 L=8 L=9 L=10

  • Tc/J = 0.42(1)
  • 1/ν = 1.53(1)

⇐ ⇒ ν = 2/d

  • η = 0.43(2)

⇐ ⇒ γ ≃ 0.94

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 15 / 30

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Our numerical results Thermodynamic properties

MC results for 7-state PG in three dimensions: 2

Scaled correlation length ξSG/L

0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.6 0.2 0.3 0.4 0.5 0.6 0.7

ξL/L T/J

L=4 L=5 L=6 L=7 L=8 L=9 L=10

  • Length scale also diverges at

Tc/J ≃ 0.42.

FSS for ξL/L

0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5

  • 4
  • 2

2 4 6 8 10 12 14

(ξL/L)/(1+aL-ω) (T-Tc)L1/ν/J

L = 7 L = 8 L = 9 L = 10

0.2 0.25 0.3 0.35 0.4 0.45

  • 2
  • 1

1 2

  • Tc/J = 0.421(3)
  • ν = 0.68(9) ⇐

⇒ ν = 2/d

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 16 / 30

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Our numerical results Thermodynamic properties

MC results for 7-state PG in three dimensions: 3

Order-parameter distribution

P(q) = ⟨ δ ( q − √ q(2) )⟩

0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4

P(T)(Q) Q (a)

T/J=0.5002 T/J=0.4688 T/J=0.4421 T/J=0.4131 T/J=0.3841 T/J=0.3550 T/J=0.3260 T/J=0.2970

  • Temp. dep for L = 9.
  • a bimodal distribution of P(q) is compatible to 1step RSB.

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 17 / 30

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Our numerical results Thermodynamic properties

MC results for 7-state PG in three dimensions: 3

Order-parameter distribution

P(q) = ⟨ δ ( q − √ q(2) )⟩

0.01 0.02 0.03 0.04 0.05 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4

P(T)(Q) Q (b)

L=4 L=6 L=7 L=8 L=9

L dep at T ≃ 0.7Tc.

  • a bimodal distribution of P(q) is compatible to 1step RSB.

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 17 / 30

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Our numerical results Thermodynamic properties

MC results for 7-state PG in three dimensions: 4

Energy

  • 1
  • 0.9
  • 0.8
  • 0.7
  • 0.6
  • 0.5
  • 0.4
  • 0.3
  • 0.2
  • 0.1

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

e T/J

(a)

L = 4 L = 6 L = 7 L = 8 L = 9 L = 10 L = 14

Specific heat

0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

c T/J

(b)

L=4 L=6 L=7 L=8 L=9 L=10 L=14

  • No divergence of c is found at T = Tc, meaning no latent heat.
  • These indicate that it is Random First Order transition.

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 18 / 30

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Our numerical results Phase diagram of ϵ-coupled system

Phase diagram of ϵ-coupled system

Phase transition under a symmetry-broken field:

Predictions for an ϵ-coupled system

HJ(Sα, Sβ) = HJ(Sα) + HJ(Sβ) − ϵ ∑

i

δ(Si,α, Si,β)

0 < ϵ < ϵ∗

  • discontinuous jump in q
  • 1st order phase transition

with latent heat

ϵ∗ < ϵ

  • crossover in q
  • no phase transition

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 19 / 30

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Our numerical results Phase diagram of ϵ-coupled system

Clausius-Clapeyron relation of ϵ-coupled system

Carnot cycle in the ϵ-coupled system Carnot theorem Q1 T1 = Q2 T2 As T1 − T2 = ∆T, the first law gives the work W of the cycle W = Q1 − Q2 = Q1 − T2 T1 Q1 = Q1 ∆T T1 The work W is also expressed by the area as ∆q∆ϵ = Q1 ∆T T1 , = ⇒ ∆T ∆ϵ = T∆q Q1 = ⇒ dT dϵ = T∆q Q1

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 20 / 30

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Our numerical results Phase diagram of ϵ-coupled system

From Clausius-Clapeyron relation, ...

1 First-order phase boundary is

monotonic upward curve in T − ϵ phase diagram

  • ∆q ≥ 0 and Q1 ≥ 0

2 If RFOT occurs in the limit ϵ = 0

dT dϵ

  • ϵ=0

= ∞, because Q1 = 0 and ∆q > 0.

CC relation

dT dϵ = T∆q Q1

3 A mean-field prediction for annealed system gives

Tc(ϵ) = Tc(0) + O(√ϵ) with ∆q = const., yielding = ⇒ Q1 = √ϵ + · · · .

4 About critical end point...

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 21 / 30

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Our numerical results Phase diagram of ϵ-coupled system

Thermodynamics of the ϵ-coupled system

Specific heat

0 < ϵ < ϵ∗:

0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75 c T/J ε=0.0008 L=8 L=10 L=12 L=14

ϵ∗ < ϵ:

0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95

c T/J

ε=0.012 L=8 L=10 L=12 L=14

Overlap

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.4 0.45 0.5 0.55 0.6 0.65 0.7 0.75 q T/J ε=0.0008 L=8 L=10 L=12 L=14 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 q T/J ε=0.0120 L=8 L=10 L=12 L=14 Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 22 / 30

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Our numerical results Phase diagram of ϵ-coupled system

Phase diagram of 3d Potts glass model in ϵ − T

0.4 0.45 0.5 0.55 0.6 0.65

0.002 0.004 0.006 0.008 0.01 0.012

T/J ε Tc from g4 Tc from ξL/L

  • Our result is consistent with 1st order transition temperature with

infinite slope at ϵ = 0, suggesting RFOT at ϵ = 0.

  • Critical endpoint:0.008 < ϵ∗ < 0.012

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 23 / 30

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Our numerical results Dynamical properties

Dynamics –auto-correlation function and susceptibility–

  • Autocorrelation function:C(t; tw) = 1

N ∑

i

Si(tw) · Si(t + tw) 1 − 1/p

  • Dynamical susceptibility (four-point correlation function) χ4:

χ4(t; tw) = N [ ⟨C(t; tw)2⟩ − ⟨C(t; tw)⟩2]

  • lim

t→∞ lim tw→∞ χ4(∞; ∞) = χSG: Static spin-glass susceptibility

  • (Left)χ4 increases

monotonically for no-RFOT case

  • (right)χ4 has a peak at

finite time t and its height diverges at T = Td for RFOT case.

non-RFOT case RFOT case

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 24 / 30

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Our numerical results Dynamical properties

Dynamical properties in 3d Potts glass model –Auto-correlation function C(t)–

L = 6

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 100 102 104 106 108 1010 c(t) t(MCS)

L = 6

T/J = 0.852 T/J = 0.781 T/J = 0.711 T/J = 0.640 T/J = 0.605 T/J = 0.570 T/J = 0.548 T/J = 0.527 T/J = 0.506 T/J = 0.491 T/J = 0.477 T/J = 0.463 T/J = 0.449 T/J = 0.435 T/J = 0.429 T/J = 0.421 T/J = 0.414 T/J = 0.407

L = 8

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 100 102 104 106 108 1010 c(t) t(MCS)

L = 8

T/J = 0.852 T/J = 0.781 T/J = 0.711 T/J = 0.640 T/J = 0.605 T/J = 0.570 T/J = 0.548 T/J = 0.527 T/J = 0.506 T/J = 0.491 T/J = 0.477 T/J = 0.463 T/J = 0.449 T/J = 0.435 T/J = 0.429 T/J = 0.421 T/J = 0.414 T/J = 0.407

L = 10

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 100 102 104 106 108 1010 c(t) t(MCS)

L = 10

T/J = 0.852 T/J = 0.781 T/J = 0.711 T/J = 0.640 T/J = 0.605 T/J = 0.570 T/J = 0.548 T/J = 0.527 T/J = 0.506 T/J = 0.491 T/J = 0.477 T/J = 0.463 T/J = 0.449 T/J = 0.435 T/J = 0.429 T/J = 0.421 T/J = 0.414 T/J = 0.407

L = 12

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 100 102 104 106 108 1010 c(t) t(MCS)

L = 12

T/J = 0.852 T/J = 0.781 T/J = 0.711 T/J = 0.640 T/J = 0.605 T/J = 0.570 T/J = 0.548 T/J = 0.527 T/J = 0.506 T/J = 0.491 T/J = 0.477 T/J = 0.463 T/J = 0.449 T/J = 0.435 T/J = 0.429 T/J = 0.421 T/J = 0.414 T/J = 0.407

  • Static SG transition is located on boundary between blue and red.
  • No plateau is found, in contrast to the mean-field prediction
  • No dynamical singularity at Td is also found.

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 25 / 30

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Our numerical results Dynamical properties

Dynamical properties in 3d Potts glass model –dynamical susceptibility χ4(t)–

L = 6

2 4 6 8 10 12 14 16 18 20 100 101 102 103 104 105 106 107

χ4(t; tw) t - tw(MCS) L = 6

T/J = 0.847 T/J = 0.796 T/J = 0.745 T/J = 0.694 T/J = 0.643 T/J = 0.593 T/J = 0.542 T/J = 0.516 T/J = 0.491 T/J = 0.478 T/J = 0.465 T/J = 0.453

L = 8

2 4 6 8 10 12 14 16 18 20 100 101 102 103 104 105 106 107

χ4(t; tw) t - tw(MCS) L = 8

T/J = 0.847 T/J = 0.796 T/J = 0.745 T/J = 0.694 T/J = 0.643 T/J = 0.593 T/J = 0.542 T/J = 0.516 T/J = 0.491 T/J = 0.478 T/J = 0.465 T/J = 0.453

L = 10

2 4 6 8 10 12 14 16 18 20 100 101 102 103 104 105 106 107

χ4(t; tw) t - tw(MCS) L = 10

T/J = 0.847 T/J = 0.796 T/J = 0.745 T/J = 0.694 T/J = 0.643 T/J = 0.593 T/J = 0.542 T/J = 0.516 T/J = 0.491 T/J = 0.478 T/J = 0.465 T/J = 0.453

L = 12

2 4 6 8 10 12 14 16 18 20 100 101 102 103 104 105 106 107

χ4(t; tw) t - tw(MCS) L = 12

T/J = 0.847 T/J = 0.796 T/J = 0.745 T/J = 0.694 T/J = 0.643 T/J = 0.593 T/J = 0.542 T/J = 0.516 T/J = 0.491 T/J = 0.478 T/J = 0.465 T/J = 0.453

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 26 / 30

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Our numerical results Dynamical properties

Dynamical properties in 3d Potts glass model –dynamical susceptibility χ4(t)–

L = 6

2 4 6 8 10 12 14 16 18 20 100 101 102 103 104 105 106 107

χ4(t; tw) t - tw(MCS) L = 6

T/J = 0.847 T/J = 0.796 T/J = 0.745 T/J = 0.694 T/J = 0.643 T/J = 0.593 T/J = 0.542 T/J = 0.516 T/J = 0.491 T/J = 0.478 T/J = 0.465 T/J = 0.453

L = 12

2 4 6 8 10 12 14 16 18 20 100 101 102 103 104 105 106 107

χ4(t; tw) t - tw(MCS) L = 12

T/J = 0.847 T/J = 0.796 T/J = 0.745 T/J = 0.694 T/J = 0.643 T/J = 0.593 T/J = 0.542 T/J = 0.516 T/J = 0.491 T/J = 0.478 T/J = 0.465 T/J = 0.453

  • Before equilibrium limit t → ∞, χ4(t) has a peak at certain time scale
  • The time scale and the peak height have a divergent tendency
  • χ4 in equilibrium limit diverges at Tc.

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 26 / 30

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Our numerical results Dynamical properties

Dynamical properties in 3d Potts glass model

Temperature dependence of the peak in χ4

1 10 0.1 1 10

χ4(t*;tw) Tc/(T-Tc)

L = 12 L = 10 L = 8 L = 6

  • Peak height χ4(t∗) in χ4 diverges at Tc not Td: χ4(t∗) ∼ |T − Tc|−γ∗
  • χ4(t∗) has singularity stronger than static χ4(∞): χ4(∞) ∼ |T − Tc|−γ

γ∗ > γ = ⇒Separation between static and dynamics singularities

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 27 / 30

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Summary

Outline

1 Spin glasses and Random First-Order Transition 2 Potts glass model 3 Our numerical results

Thermodynamic properties Phase diagram of ϵ-coupled system Dynamical properties

4 Summary

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 28 / 30

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Summary

Summary

  • Random first-order transition (RFOT) of spin glasses
  • 7-state Potts glass model in three dimensions with 1st, 2nd, and 3rd

neighbor couplings.

Our findings

  • Phys. Rev. E 91, 020102(R)(2015)
  • SG transition at finite temperature Tc.
  • A critical exponent ν = 0.68(9) ∼ 2/d.
  • Overlap has a jump at Tc without latent heat.
  • P(q) has double-peak structure at and below Tc.
  • These features are compatible to 1RSB.
  • This model is a strong candidate which displays RFOT in three

dimensions.

  • A dynamical singularity in flucutuation is found, indicating a possibility
  • f Td ≃ Tc.

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 29 / 30

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Summary

Summary

This research is one step toward the understanding of thermodynamic glass transitions as a transition from liquid to disordered solid.

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 29 / 30

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Summary

Summary

This research is one step toward the understanding of thermodynamic glass transitions as a transition from liquid to disordered solid. Thank you for your attention.

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 29 / 30

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Summary

Financial support

  • 2013-2018 Grant-in-Aid for Scientific Research on Innovative Areas,

MEXT, Japan “Initiative for High-Dimensional Data-Driven Science through Deepening of Sparse Modeling”

  • JPS Core-to-Core program 2013-2015, “Non-equilibrium dynamics of

soft matter and information”

Koji Hukushima (Univ. of Tokyo@Komaba) RFOT of spin glasses in 3d 14 August, 2015 30 / 30