Related Experiment Video
Updated: Aug 2, 2025
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
9.0K
From Dual Unitarity to Generic Quantum Operator Spreading
Michael A Rampp1, Roderich Moessner1, Pieter W Claeys1
1Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany.
Physical Review Letters
|April 17, 2023
Summary
Weakly breaking dual unitarity in quantum many-body systems restores generic chaotic dynamics. This study reveals how operator spreading and butterfly velocity recover ergodic behavior, crucial for understanding quantum chaos.
Area of Science:
- Quantum Many-Body Physics
- Quantum Chaos
- Statistical Mechanics
Background:
- Dual-unitary circuits offer exact solvability but exhibit non-generic dynamics.
- Understanding deviations from dual unitarity is key to exploring generic quantum many-body behavior.
Purpose of the Study:
- To investigate how small perturbations to dual unitarity affect local operator spreading.
- To determine if broken dual unitarity recovers generic ergodic dynamics in quantum spin chains.
Main Methods:
- Developing a discrete path-integral formula for out-of-time-order correlators.
- Analyzing the butterfly velocity and operator front broadening.
Main Results:
- Recovered a butterfly velocity (vB) smaller than the light-cone velocity (vLC).
- Observed a diffusively broadening operator front, characteristic of ergodic systems.
- Found that butterfly velocity and diffusion constant depend on microscopic quantities and gate operator entanglement.
Conclusions:
- Weakly broken dual unitarity restores generic, ergodic quantum many-body dynamics.
- Operator entanglement plays a critical role in the recovery of these dynamics.
- The findings provide insights into the transition from solvable to chaotic quantum systems.
Related Concept Videos
03:06The Pauli Exclusion Principle
41.7K
The arrangement of electrons in the orbitals of an atom is called its electron configuration. We describe an electron configuration with a symbol that contains three pieces of information:
41.7K
00:59Propagation of Uncertainty from Random Error
751
An experiment often consists of more than a single step. In this case, measurements at each step give rise to uncertainty. Because the measurements occur in successive steps, the uncertainty in one step necessarily contributes to that in the subsequent step. As we perform statistical analysis on these types of experiments, we must learn to account for the propagation of uncertainty from one step to the next. The propagation of uncertainty depends on the type of arithmetic operation performed on...
751
01:10Interpreting ¹H NMR Signal Splitting: The (n + 1) Rule
1.4K
In the AX proton spin system, proton A can sense the two spin states of a coupled proton X, resulting in a doublet NMR signal with two peaks of equal (1:1) intensity. When proton A is coupled to two equivalent protons (AX2 spin system), the spin states of each X can be aligned with or against the external field, creating three possible scenarios. This results in a 1:2:1 triplet signal, where the central peak corresponds to the chemical shift of A and is twice as large or intense as the...
1.4K
01:10Propagation of Uncertainty from Systematic Error
571
The atomic mass of an element varies due to the relative ratio of its isotopes. A sample's relative proportion of oxygen isotopes influences its average atomic mass. For instance, if we were to measure the atomic mass of oxygen from a sample, the mass would be a weighted average of the isotopic masses of oxygen in that sample. Since a single sample is not likely to perfectly reflect the true atomic mass of oxygen for all the molecules of oxygen on Earth, the mass we obtain from this...
571
03:35Hybridization of Atomic Orbitals II
32.6K
sp3d and sp3d 2 Hybridization
32.6K
01:26Singularity Functions for Shear
168
In structural analysis, singularity functions are crucial in simplifying the representation of shear forces in beams under discontinuous loading. These functions describe discontinuous variations in shear force across a beam with varying loads by using a single mathematical expression, regardless of the complexity of the loading conditions. The singularity functions are derived from creating a free-body diagram of the beam and then making conceptual cuts at specific points to examine the...
168