Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · 2308.02218

Long-term Oscillations and Universal Behavior in Pulsed Electric Fields

Leila Shahkarami·Farid Charmchi
View original source ↗Read source document ↗Export metadata ↓

Abstract

We thoroughly analyze the response of the zero-temperature N=2 super Yang-Mills theory to time-dependent electric field quenches via holography. We specially focus on transient pulse-like configurations for the electric field, characterized by some model parameters, such as the maximum value of the electric field $E_0$ and the ramping time $\delta_t$ which determines the time interval for switching the electric field on and off. We also compare some of the results with those of tanh-like quenches. The term tanh-like quench is used for a quench that rises from zero to a final finite value during a finite amount of time. Our numerical solutions demonstrate that when the system is subjected to pulse-like electric field quenches, the emerged electric current as a response goes through three stages as time passes. After excitation and rapidly-damping oscillatory stages, it experiences a long-lasting periodic oscillatory region. In fact the effect of the electric pulse remains in the system much longer than the duration of the presence of the electric field itself. It is extremely interesting that, as confirmed by power spectrum diagrams, these oscillations have a unique obvious frequency which is independent of the details of the electric pulse function and its parameters. Moreover, we observe a universal behavior in the adiabatic limit, when the ramping time tends to infinity. In this limit, the early and late time dynamics of the response electric current does not depend on the time dependence of the electric field. In particular, we see that for both pulse-like and tanh-like quenches, the maximum value at the first peak of the oscillations approaches the static value of the current induced by the presence of a static electric field $E_0$. However, the fast quench behavior differs extremely for different kinds of quench functions.

Explore related subjects

hep-th

Keep this discovery

BibTeXRIS

Leila Shahkarami, Farid Charmchi. 2023-08-04. Long-term Oscillations and Universal Behavior in Pulsed Electric Fields. https://arxiv.org/abs/2308.02218

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Timelike Entanglement from Spacetime Density Matrices: A Lattice Realization

We investigate timelike entanglement in quantum field theory using spacetime density matrices and provide a microscopic lattice realization. For a two-dimensional free real scalar field, we extend Gaussian diagonalization methods to the generally non-Hermitian reduced spacetime density matrix and determine its complete nonzero spectrum in the generic regular case, together with all integer R\'enyi moments. The real-time replica construction identifies these moments with Lorentzian branch-point twist-operator correlation functions. We test this identification against the full four-point function on a circle, boundary two-point functions with Dirichlet and Neumann boundary conditions, and massive form-factor predictions, finding quantitative agreement in both magnitude and phase across distinct causal regimes. The boundary setup exhibits a finite causally connected window in which every integer R\'enyi entropy is real, showing that reality is not equivalent to causal disconnection. These results provide a microscopic lattice foundation for timelike entanglement and for Lorentzian twist-operator methods beyond equal-time regions.

hep-th↗
arXiv2026

Landau-Ginzburg description of an exceptional ${\mathcal N}=1$ minimal model

The $\mathcal N=1$ superconformal minimal model with $m=12$ and the exceptional modular invariant $(E_6,D_8)$ is the unitary minimal model of the super-$W_3$ algebra. We propose its Landau-Ginzburg description using two real scalar superfields with the cubic superpotential ${\cal W}=g_1 XY^2/2 + g_2X^3/6$. For $g_1=g_2$, this superpotential is known to describe a product of two $m=3$ $\mathcal N=1$ superconformal minimal models, which is the $m=10$ model with the $(D_6,E_6)$ modular invariant. The exceptional $m=12$ superconformal minimal model is realized at a different fixed point of the same theory. Testing this Landau-Ginzburg description requires the fusion ring of the minimal model, which we obtain from the modular data of the extended algebra. The fusion ring has a $\mathbb Z_2$ grading by chiral fermion parity that the ordinary fusion coefficients do not determine. This grading, composed with conjugation, gives the generator of the R-parity $\mathbb Z_2^{R}$ of the Landau-Ginzburg theory. We then treat the theory with superpotential $\cal W$ as a Gross-Neveu-Yukawa model in $d=4-\epsilon$ and find a weakly coupled infrared fixed point with $g_1/g_2=3/2+\mathcal O(\epsilon)$, at which supersymmetry emerges. We also describe the renormalization group flow from this fixed point to the decoupled fixed point with $g_1=g_2$. The operator dimensions at the coupled fixed point, continued to $d=2$, agree approximately with their values in the $m=12$ superconformal minimal model. Finally, we estimate the scaling dimensions in the new interacting $d=3$ $\mathcal N=1$ superconformal field theory.

hep-th↗
arXiv2026

Detecting one-dimensional bosonic SPT phases via twisted entropic order parameter

Entanglement asymmetry, introduced by F. Ares, S. Murciano and P. Calabrese, provides a density-matrix diagnostic of symmetry breaking and successfully captures the Landau data associated with a broken symmetry pattern. However, it is by now well established that gapped quantum many-body systems can exhibit phases which are not characterized solely by Landau symmetry breaking. A fundamental example is a symmetry-protected topological (SPT) phase, and the ordinary definition of entanglement asymmetry is insensitive to this topological information. In this work we introduce a refined quantity, which we call the twisted entropic order parameter, designed to detect SPT phases from reduced density matrices, particularly focusing on one-dimensional bosonic systems. The key ingredient in our construction is an ancilla degrees of freedom that coherently records the untwisted state and the twisted state associated to a one-ended topological defect of unbroken symmetry, so that the enlarged density matrix retains the charge carried by the defect endpoint. We demonstrate our proposal in concrete lattice models and further generalize it beyond ordinary group symmetries, establishing its ability to diagnose SPT phases. This provides a first step toward a unified entanglement-asymmetry framework for diagnosing quantum phases of matter.

hep-th↗