# Diverging Quantum Speed Limits: A Herald of Classicality

@article{Poggi2021DivergingQS, title={Diverging Quantum Speed Limits: A Herald of Classicality}, author={Pablo M. Poggi and Steve Campbell and Sebastian Deffner}, journal={PRX Quantum}, year={2021} }

This material is based upon work supported by the
U.S. Department of Energy, Office of Science, National
Quantum Information Science Research Centers, Quantum Systems Accelerator. S.C. gratefully acknowledges
the Science Foundation Ireland Starting Investigator Research Grant “SpeedDemon” (No. 18/SIRG/5508) for financial support. S.D. acknowledges support from the U.S.
National Science Foundation under Grant No. DMR2010127.

## 6 Citations

### Quantum optimal control in quantum technologies. Strategic report on current status, visions and goals for research in Europe

- PhysicsEPJ Quantum Technology
- 2022

Quantum optimal control, a toolbox for devising and implementing the shapes of external fields that accomplish given tasks in the operation of a quantum device in the best way possible, has evolved…

### Phase space geometry and optimal state preparation in quantum metrology with collective spins

- Computer Science
- 2022

This work revisits well-known protocols in quantum metrology using collective spins and proposes a uni-fying picture for optimal state preparation based on a semiclassical description in phase space, and proves a no-go theorem for the local optimality of these models for p > 2.

### Speed of evolution in entangled fermionic systems

- PhysicsJournal of Physics A: Mathematical and Theoretical
- 2022

We consider the simplest identical-fermion system that exhibits the phenomenon of entanglement (beyond exchange correlations) to analyze its speed of evolution toward an orthogonal state, and revisit…

### Analyticity constraints bound the decay of the spectral form factor

- PhysicsQuantum
- 2022

Quantum chaos cannot develop faster than λ≤2π/(ℏβ) for systems in thermal equilibrium [Maldacena, Shenker & Stanford, JHEP (2016)]. This `MSS bound' on the Lyapunov exponent λ is set by the width of…

### Memory Effects in High-Dimensional Systems Faithfully Identified by Hilbert–Schmidt Speed-Based Witness

- MathematicsEntropy
- 2022

A witness of non-Markovianity based on the Hilbert–Schmidt speed (HSS), a special type of quantum statistical speed, has been recently introduced for low-dimensional quantum systems. Such a…

### PAN: Pulse Ansatz on NISQ Machines

- Computer ScienceArXiv
- 2022

PAN is a native-pulse ansatz generator framework for VQAs that improves the performance with decreased latency and demonstrates advantages on QAOA tasks even with considerable noises in NISQ machines.

## References

SHOWING 1-10 OF 61 REFERENCES

### Classical and quantum speed limits

- PhysicsQuantum
- 2021

It is shown that the new bound on quantum speed limit is derived by applying the original Mandelstam-Tamm one to the evolution in the space of Hilbert-Schmidt operators acting in the initial space of states and provides the quantum counterpart of the classical speed limit.

### Quantum Speed Limits across the Quantum-to-Classical Transition.

- PhysicsPhysical review letters
- 2018

This work explores quantum speed limits across the quantum-to-classical transition and identifies equivalent bounds in the classical world, and shows that speed limits exist for both quantum and classical systems.

### Tightening Quantum Speed Limits for Almost All States.

- PhysicsPhysical review letters
- 2018

This work derives two quantum speed limits for unitary driving that outperform the traditional bounds for almost all quantum states and are significantly simpler to compute as well as experimentally more accessible.

### Quantum speed limit for physical processes.

- PhysicsPhysical review letters
- 2013

It is shown that it is possible to extend the minimal evolution time between two distinguishable states of a system to nonunitary processes, using an attainable lower bound that is connected to the quantum Fisher information for time estimation.

### Quantum Speed Limit is Not Quantum.

- PhysicsPhysical review letters
- 2018

This study obtains a classical speed limit corresponding to the QSL using Hilbert space for the classical Liouville equation and obtains similar speed limits for the imaginary-time Schrödinger equations such as the classical master equation.

### Geometry of quantum evolution.

- PhysicsPhysical review letters
- 1990

It is shown that the integral of the uncertainty of energy with respect to time is independent of the particular Hamiltonian used to transport the quantum system along a given curve in the projective Hilbert space, which gives a new time-energy uncertainty principle.

### Gaussian states in continuous variable quantum information

- Physics
- 2005

These notes originated out of a set of lectures in Quantum Optics and Quantum Information given by one of us (MGAP) at the University of Napoli and the University of Milano. A quite broad set of…

### Quantum speed limits—primer, perspectives, and potential future directions

- PhysicsQuantum Inf. Process.
- 2016

An expository review of the development of these quantum speed limit inequalities, including extensions to different energy statistics and generalizations to mixed system states and open and multipartite systems.

### Quantum speed limit for non-Markovian dynamics.

- PhysicsPhysical review letters
- 2013

A Margolus-Levitin-type bound on the minimal evolution time of an arbitrarily driven open quantum system is derived and it is shown that non-Markovian effects can speed up quantum evolution and therefore lead to a smaller quantum speed limit time.

### Probing Quantum Speed Limits with Ultracold Gases.

- PhysicsPhysical review letters
- 2021

It is theoretically proposed how to measure QSLs in an ultracold quantum gas confined in a time-dependent harmonic trap, and whether the dynamics is self-similar by measuring as a function of time the cloud size of the ultracolds gas, which makes it possible to determine the Bures angle and energy fluctuations.