Short-time universal scaling and light-cone dynamics after a quench in an isolated quantum system in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>d</mml:mi></mml:math>spatial dimensions

Chiocchetta, Alessio; Tavora, Marco; Gambassi, Andrea; Mitra, Aditi

doi:10.1103/physrevb.94.134311

Cited by 53 publications

(97 citation statements)

References 125 publications

(291 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As in equilibrium, observables will have a singular dependence on the detuning from the critical point. Such singular behavior in quench dynamics has already been identified for bosonic systems coupled to a bath [15][16][17][18][19] , and also for isolated bosonic systems [20][21][22][23][24][25][26][27] . In this paper, we complement this study with that for an isolated fermionic system.…”

Section: Introductionmentioning

confidence: 78%

See 1 more Smart Citation

Time-resolved spectral density of interacting fermions following a quench to a superconducting critical point

Lemonik

Mitra

2017

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

Results are presented for the time evolution of fermions initially in a non-zero temperature normal phase, following the switch on of an attractive interaction. The dynamics are studied in the disordered phase close to the critical point, where the superfluid fluctuations are large. The analysis is conducted within a two-particle irreducible, large N approximation. The system is considered from the perspective of critical quenches where it is shown that the fluctuations follow universal model A dynamics. A signature of this universality is found in a singular correction to the fermion lifetime, given by a scaling form, where d is the spatial dimension, t is the time since the quench, and ε is the fermion energy. The singular behavior of the spectral density is interpreted as arising due to incoherent Andreev reflections off superfluid fluctuations.

show abstract

Section: Introductionmentioning

confidence: 78%

“…However τ −1 only depends on ImS 3 (β) where β is a material dependent parameter, see Eq. (24). Further as ImS 3 has a logarithmic dependence on the cutoff, changing the (materialdependent) cutoff shifts ImS 3 (x) → ImS 3 (x) + γ.…”

Section: A Propagator For Interacting Cooperonsmentioning

confidence: 98%

Time-resolved spectral density of interacting fermions following a quench to a superconducting critical point

Lemonik

Mitra

2017

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

show abstract

“…We stress that, whereas in [31][32][33][34][35][36] scaling evolution after quenches of the gap and interaction parameters from a thermal initial state have been discussed in the context of a large-N approximation applied to a scalar O(N) model, as well as perturbative, ε-expansion, and functional RG, the resulting scaling forms do not allow for the scaling to be discussed here. While the cited work accounts for scaling in the context of critical coarsening, initial-slip dynamics and ageing phenomena [18,[82][83][84][85], for the type of quenches considered there, the same (initial-slip) scaling exponent results for the correlation and response functions [85].…”

Section: Concluding Remarks On the Scaling Dynamicsmentioning

confidence: 99%

Low-energy effective theory of nonthermal fixed points in a multicomponent Bose gas

2019

View full text Add to dashboard Cite

Non-thermal fixed points in the evolution of a quantum many-body system quenched far out of equilibrium manifest themselves in a scaling evolution of correlations in space and time. We develop a low-energy effective theory of non-thermal fixed points in a bosonic quantum many-body system by integrating out long-wavelength density fluctuations. The system consists of N distinguishable spatially uniform Bose gases with U(N)symmetric interactions. The effective theory describes interacting Goldstone modes of the total and relativephase excitations. It is similar in character to the non-linear Luttinger-liquid description of low-energy phonons in a single dilute Bose gas, with the markable difference of a universal non-local coupling function depending, in the large-N limit, only on momentum, single-particle mass, and density of the gas. Our theory provides a perturbative description of the non-thermal fixed point, technically easy to apply to experimentally relevant cases with a small number of fields N. Numerical results for N = 3 allow us to characterize the analytical form of the scaling function and confirm the analytically predicted scaling exponents. The fixed point which is dominated by the relative phases is found to be Gaussian, while a non-Gaussian fixed point is anticipated to require scaling evolution with a distinctly lower power of time.

show abstract

“…Closely related dynamical critical phenomena include (wave-)turbulence [13,14], as well as superfluid or quantum turbulence [15,16]. Universal scaling far from equilibrium has recently been analyzed for different types of quantum quenches [17][18][19][20][21][22][23][24][25][26][27][28], see also [29][30][31][32][33] for studies of phase-ordering kinetics in ultracold Bose gases. While coarsening phenomena have partly been associated with the standard dynamical universality classes [11], a rigorous renormalization-group…”

Section: Introductionmentioning

confidence: 99%

Strongly anomalous non-thermal fixed point in a quenched two-dimensional Bose gas

2017

View full text Add to dashboard Cite

Universal scaling behavior in the relaxation dynamics of an isolated two-dimensional Bose gas is studied by means of semi-classical stochastic simulations of the Gross-Pitaevskii model. The system is quenched far out of equilibrium by imprinting vortex defects into an otherwise phase-coherent condensate. A strongly anomalous non-thermal fixed point is identified, associated with a slowed decay of the defects in the case that the dissipative coupling to the thermal background noise is suppressed. At this fixed point, a large anomalous exponent h - 3 and, related to this, a large dynamical exponent  z 5 are identified. The corresponding power-law decay is found to be consistent with three-vortex-collision induced loss. The article discusses these aspects of non-thermal fixed points in the context of phaseordering kinetics and coarsening dynamics, thus relating phenomenological and analytical approaches to classifying far-from-equilibrium scaling dynamics with each other. In particular, a close connection between the anomalous scaling exponent η, introduced in a quantum-field theoretic approach, and conservation-law induced scaling in classical phase-ordering kinetics is revealed. Moreover, the relation to superfluid turbulence as well as to driven stationary systems is discussed. analysis as well as a comprehensive classification scheme of far-from-equilibrium universal dynamics are lacking so far.Here we consider possible universal scaling behavior of a time-evolving isolated two-dimensional (2D) quantum-degenerate Bose gas quenched far out of equilibrium. We discuss the numerically found scaling in time and in the spatial degrees of freedom in the framework of non-thermal fixed points [34][35][36][37][38]. This approach builds on a scaling analysis of non-perturbative dynamic equations for field correlation functions in the spirit of a renormalization-group approach to far-from-equilibrium dynamics [35,[39][40][41][42][43][44]. Close to a non-thermal fixed point, correlation functions show a time evolution which takes the form of a rescaling in space and time [38]. In consequence, the relaxation is critically slowed down, while correlations evolve as a power law rather than exponentially in time.We prepare far-from-equilibrium states by imprinting phase defects, i.e., quantum vortex excitations, into an otherwise strongly phase-coherent condensate. Different kinds of initial states are realized by varying the number of defects, their arrangement, and their winding numbers. Independently of the microscopic details of the initial state, such as the statistics of fluctuations, the system is attracted to one or more non-thermal fixed points where the information about these details gets lost. Close to such a fixed point the correlations exhibit and evolve according to universal power laws [45][46][47][48][49][50].More than one attractor can exist for the dynamical evolution of the system, as we will demonstrate being the case for the 2D Bose gas studied here. Consequently, different types of universal evolution wit...

show abstract

Short-time universal scaling and light-cone dynamics after a quench in an isolated quantum system indspatial dimensions

Cited by 53 publications

References 125 publications

Time-resolved spectral density of interacting fermions following a quench to a superconducting critical point

Time-resolved spectral density of interacting fermions following a quench to a superconducting critical point

Low-energy effective theory of nonthermal fixed points in a multicomponent Bose gas

Strongly anomalous non-thermal fixed point in a quenched two-dimensional Bose gas

Contact Info

Product

Resources

About