# Observation of Time-Crystalline Eigenstate Order on a Quantum Processor

@inproceedings{Mi2021ObservationOT, title={Observation of Time-Crystalline Eigenstate Order on a Quantum Processor}, author={Xiao Mi and Matteo Ippoliti and Chris Quintana and Amy Greene and Zijun Chen and Jonathan A. Gross and Frank Arute and Kunal Arya and Juan Atalaya and Ryan Babbush and Joseph C. Bardin and Joao Basso and Andreas Bengtsson and Alexander Bilmes and Alexandre Bourassa and Leon Brill and Mick Broughton and Bob B. Buckley and David A. Buell and Brian Burkett and Nicholas Bushnell and Benjamin Chiaro and Roberto Collins and William Courtney and Dripto M. Debroy and Sean Demura and Alan R. Derk and Andrew Dunsworth and Daniel Eppens and Catherine Erickson and Edward Farhi and Austin G. Fowler and Brooks Foxen and Craig Gidney and Marissa Giustina and Matthew P. Harrigan and Sean D. Harrington and Jeremy P. Hilton and Alan Ho and Sabrina Hong and Trent Huang and Ashley Huff and William J. Huggins and L B Ioffe and Sergei V. Isakov and Justin Iveland and Evan Jeffrey and Zhang Jiang and Cody Jones and Dvir Kafri and Tanuj Khattar and Seon Kim and Alexei Kitaev and Paul Klimov and Alexander N. Korotkov and Fedor Kostritsa and David Landhuis and Pavel Laptev and Joonho Lee and Kenny Lee and Aditya Locharla and Erik Lucero and Orion Martin and Jarrod R. McClean and Trevor McCourt and Matthew J. McEwen and Kevin C. Miao and Masoud Mohseni and Shirin Montazeri and Wojciech Mruczkiewicz and Ofer Naaman and Matthew Neeley and Charles J. Neill and Michael Newman and Murphy Yuezhen Niu and Thomas F. O' Brien and Alexander Opremcak and Eric P. Ostby and B{\'a}lint Pat{\'o} and Andre Petukhov and Nicholas C Rubin and Daniel Thomas Sank and Kevin J Satzinger and Vladimir Shvarts and Yuan Su and Doug Strain and Marco Szalay and Matthew D Trevithick and Benjamin Villalonga and Theodore White and Z. Jamie Yao and P Yeh and Juhwan Yoo and Adam Zalcman and Hartmut Neven and Sergio Boixo and Vadim N. Smelyanskiy and Anthony Megrant and Julian Kelly and Yu Chen and S. L. Sondhi and Roderich Moessner and Kostyantyn Kechedzhi and Vedika Khemani and Pedram Roushan}, year={2021} }

Quantum many-body systems display rich phase structure in their low-temperature equilibrium states. However, much of nature is not in thermal equilibrium. Remarkably, it was recently predicted that out-of-equilibrium systems can exhibit novel dynamical phases that may otherwise be forbidden by equilibrium thermodynamics, a paradigmatic example being the discrete time crystal (DTC). Concretely, dynamical phases can be defined in periodically driven many-body localized systems via the concept of… Expand

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#### References

SHOWING 1-10 OF 51 REFERENCES

Localization-protected quantum order

- Physics
- 2013

Closed quantum systems with quenched randomness exhibit many-body localized regimes wherein they do not equilibrate, even though prepared with macroscopic amounts of energy above their ground states.… Expand

Many-Body Localization and Thermalization in Quantum Statistical Mechanics

- Physics
- 2015

We review some recent developments in the statistical mechanics of isolated quantum systems. We provide a brief introduction to quantum thermalization, paying particular attention to the eigenstate… Expand

Colloquium
: Many-body localization, thermalization, and entanglement

- Physics
- Reviews of Modern Physics
- 2019

Thermalizing quantum systems are conventionallydescribed by statistical mechanics at equilib-rium. However, not all systems fall into this category, with many-body localization providinga generic… Expand

Many-body localization in periodically driven systems.

- Physics, Medicine
- Physical review letters
- 2015

An effective model of the MBL phase is proposed in terms of an extensive number of emergent local integrals of motion, which naturally explains the spectral and dynamical properties of this phase. Expand

Absolute stability and spatiotemporal long-range order in Floquet systems

- Physics
- 2016

Recent work has shown that a variety of novel phases of matter arise in periodically driven Floquet systems. Among these are many-body localized phases which spontaneously break global symmetries and… Expand

Critical Time Crystals in Dipolar Systems.

- Physics, Medicine
- Physical review letters
- 2017

The authors demonstrate the existence of a novel, critical DTC regime that is stabilized not by many-body localization but rather by slow, critical dynamics, and shows that the DTC response can be used as a sensitive probe of nonequilibrium quantum matter. Expand

Observation of separated dynamics of charge and spin in the Fermi-Hubbard model

- Physics
- 2020

Strongly correlated quantum systems give rise to many exotic physical phenomena, including high-temperature superconductivity. Simulating these systems on quantum computers may avoid the… Expand

Many-body localization in a disordered quantum Ising chain.

- Physics, Medicine
- Physical review letters
- 2014

Two entanglement properties that are promising for the study of the many-body localization transition are explored: the variance of the half-chainEntanglement entropy of exact eigenstates and the long time change in entanglements after a local quench from an specific eigenstate. Expand

Observation of a discrete time crystal

- Physics, Medicine
- Nature
- 2017

The experimental observation of a discrete time crystal, in an interacting spin chain of trapped atomic ions, is presented, which opens the door to the study of systems with long-range spatio-temporal correlations and novel phases of matter that emerge under intrinsically non-equilibrium conditions. Expand

Pre-thermal phases of matter protected by time-translation symmetry

- Physics, Mathematics
- 2016

In a periodically driven (Floquet) system, there is the possibility for new phases of matter, not present in stationary systems, protected by discrete time-translation symmetry. This includes… Expand