Download presentation
Presentation is loading. Please wait.
Published byClaribel Horton Modified over 9 years ago
1
N ON - EQUILIBRIUM DYNAMIC CRITICAL SCALING OF THE QUANTUM I SING CHAIN Michael Kolodrubetz Princeton University In collaboration with: Bryan Clark, David Huse David Pekker Krishnendu Sengupta
2
Q UANTUM STATE OF TRANSVERSE - FIELD I SING MODEL DURING SLOW RAMP IS … Universal Non-equilibrium Experimentally viable Non-thermal Dephasing resistant
3
C LASSICAL P HASE T RANSITIONS “Magnetization” Landau-Ginzburg functional
4
C LASSICAL P HASE T RANSITIONS “Magnetization”
5
Thermal fluctuations C LASSICAL P HASE T RANSITIONS
6
Q UANTUM P HASE T RANSITIONS One-dimensional transverse-field Ising chain
7
Q UANTUM P HASE T RANSITIONS One-dimensional transverse-field Ising chain Paramagnet (PM) Ferromagnet (FM)
8
Q UANTUM P HASE T RANSITIONS One-dimensional transverse-field Ising chain Paramagnet (PM) Ferromagnet (FM) Quantum fluctuations
9
C RITICAL S CALING [Smirnov, php.math.unifi.it/users/paf/ LaPietra/files/Chelkak01.ppt]
10
C RITICAL S CALING [Smirnov, php.math.unifi.it/users/paf/ LaPietra/files/Chelkak01.ppt]
11
C RITICAL S CALING Correlation length critical exponent Dynamic critical exponent, [Smirnov, php.math.unifi.it/users/paf/ LaPietra/files/Chelkak01.ppt]
12
C RITICAL S CALING, Ising: Correlation length critical exponent Dynamic critical exponent
13
C RITICAL S CALING, Ising: Correlation length critical exponent Dynamic critical exponent Order parameter critical exponent
14
C RITICAL S CALING, Ising: Correlation length critical exponent Dynamic critical exponent Order parameter critical exponent
15
K IBBLE -Z UREK RAMPS Ramp rate
16
K IBBLE -Z UREK RAMPS Ramp rate
17
K IBBLE -Z UREK RAMPS Adiabatic Ramp rate
18
K IBBLE -Z UREK RAMPS Adiabatic Impulse Ramp rate
19
K IBBLE -Z UREK RAMPS Adiabatic Impulse Ramp rate
20
K IBBLE -Z UREK RAMPS Adiabatic Impulse Ramp rate
21
K IBBLE -Z UREK RAMPS Adiabatic Impulse Ramp rate
22
K IBBLE -Z UREK RAMPS Adiabatic Impulse Ramp rate
23
K IBBLE -Z UREK RAMPS METHODIDEAWHEN IT WORKS “Old-school” Kibble-Zurek [Kibble 1976, Zurek 1985] and set the “interesting” time and length scales -Ramp to the QCP -Ramp to deep in the FM phase
24
K IBBLE -Z UREK RAMPS METHODIDEAWHEN IT WORKS “Old-school” Kibble-Zurek [Kibble 1976, Zurek 1985] and set the “interesting” time and length scales -Ramp to the QCP -Ramp to deep in the FM phase Kibble-Zurek scaling [Deng et. al. 2008, Erez et. al., in prep., Polkovnikov, …] Most quantities show scaling collapse when scaled by and Throughout the ramp
25
K IBBLE -Z UREK RAMPS Adiabatic Impulse Ramp rate
26
K IBBLE -Z UREK RAMPS Adiabatic Impulse Ramp rate
27
K IBBLE -Z UREK RAMPS Adiabatic Impulse Ramp rate
28
K IBBLE -Z UREK RAMPS Adiabatic Impulse Ramp rate
29
T RANSVERSE - FIELD I SING CHAIN Sachdev: “Quantum Phase Transitions”
30
T RANSVERSE - FIELD I SING CHAIN Wigner fermionize Sachdev: “Quantum Phase Transitions” phase
31
T RANSVERSE - FIELD I SING CHAIN Wigner fermionize Sachdev: “Quantum Phase Transitions” phase
32
T RANSVERSE - FIELD I SING CHAIN Wigner fermionize Quadratic Integrable Sachdev: “Quantum Phase Transitions” phase
33
T RANSVERSE - FIELD I SING CHAIN Wigner fermionize Quadratic Integrable Hamiltonian conserves parity for each mode k Sachdev: “Quantum Phase Transitions” phase
34
T RANSVERSE - FIELD I SING CHAIN Wigner fermionize Quadratic Integrable Hamiltonian conserves parity for each mode k Work in subspace where parity is even Sachdev: “Quantum Phase Transitions” phase
35
T RANSVERSE - FIELD I SING CHAIN Wigner fermionize Quadratic Integrable Hamiltonian conserves parity for each mode k Work in subspace where parity is even Sachdev: “Quantum Phase Transitions” phase
36
T RANSVERSE - FIELD I SING CHAIN
42
Low energy, long wavelength theory
43
K IBBLE -Z UREK RAMPS Adiabatic Impulse Ramp rate Low energy, long wavelength theory?
44
K IBBLE -Z UREK RAMPS Adiabatic Impulse Ramp rate Low energy, long wavelength theory
45
K IBBLE -Z UREK RAMPS Adiabatic Impulse Ramp rate Low energy, long wavelength theory
46
K IBBLE -Z UREK SCALING LIMIT Schrödinger Equation OR Observable Fixed
47
K IBBLE -Z UREK SCALING LIMIT
51
K IBBLE -Z UREK OBSERVABLES Excess heat Spin-spin correlation function
52
K IBBLE -Z UREK OBSERVABLES Excess heat Spin-spin correlation function
53
K IBBLE -Z UREK OBSERVABLES
60
F INITE - SIZE SCALING
62
Finite size effects can be ignored
63
F INITE - SIZE SCALING
65
E QUILIBRIUM VIA DYNAMICS KZ scaling function Equilibrium scaling function If dynamic scaling functions exist, they must have the equilibrium critical exponents
66
F INITE - SIZE SCALING
68
L ANDAU -Z ENER DYNAMICS
71
F INITE - SIZE SCALING
72
L ANDAU -Z ENER DYNAMICS
73
A THERMAL PROPERTIES
77
Inverted
78
A THERMAL PROPERTIES Kibble-Zurek
79
A THERMAL PROPERTIES Kibble-Zurek Thermal
80
D EPHASING Protocol Ramp to create excitations Freeze the Hamiltonian Wait
81
D EPHASING Protocol Ramp to create excitations Freeze the Hamiltonian Wait … …
82
D EPHASING … … Protocol Ramp to create excitations Freeze the Hamiltonian Wait
83
D EPHASING … … Protocol Ramp to create excitations Freeze the Hamiltonian Wait
84
D EPHASING … … Protocol Ramp to create excitations Freeze the Hamiltonian Wait
85
D EPHASING … … Protocol Ramp to create excitations Freeze the Hamiltonian Wait
86
D EPHASING Dephasing in integrable model: Generalized Gibb’s ensemble (GGE) … … Protocol Ramp to create excitations Freeze the Hamiltonian Wait
87
D EPHASING Dephasing in integrable model: Generalized Gibb’s ensemble (GGE) … … Does dephasing occur during the Kibble- Zurek ramp?
88
D EPHASING Dephasing in integrable model: Generalized Gibb’s ensemble (GGE) … …
89
D EPHASING Dephasing in integrable model: Generalized Gibb’s ensemble (GGE) as … …
90
D EPHASING Dephasing in integrable model: Generalized Gibb’s ensemble (GGE) as … …
91
D EPHASING Cubic ramp: … …
92
D EPHASING Cubic ramp: as … …
93
D EPHASING Cubic ramp: as … …
94
U NIVERSALITY
96
Additional terms change (renormalize) the non- universal aspects of the critical point They do not change critical scaling Critical exponents Scaling functions Debated for non-integrable system dynamics
97
U NIVERSALITY
99
Paramagnet Antiferromagnet
100
U NIVERSALITY Paramagnet Antiferromagnet Ramp the tilt ( ) linearly in time
101
U NIVERSALITY
105
C ONCLUSIONS Solved dynamic critical scaling behavior of the TFI chain Athermal negative correlations Phase-locked high order ramps Strong numerical evidence for universality Tilted boson model has same scaling functions Experimentally accessible Athermal features robust against open boundary conditions Open b.c. simplifies measurement Time scales already available [Simon et. al., 2007]
106
D EPHASING VIA QUASIPARTICLES
108
O PEN BOUNDARY CONDITIONS
111
U NIVERSALITY Remove spin ups on neighboring sites
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.