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Related papers: Strong random unitaries and fast scrambling

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The generation of $k$-designs (pseudorandom distributions that emulate the Haar measure up to $k$ moments) with local quantum circuit ensembles is a problem of fundamental importance in quantum information and physics. Despite the extensive…

Quantum Physics · Physics 2024-12-31 Zimu Li , Han Zheng , Junyu Liu , Liang Jiang , Zi-Wen Liu

Machine learning has shown significant breakthroughs in quantum science, where in particular deep neural networks exhibited remarkable power in modeling quantum many-body systems. Here, we explore how the capacity of data-driven deep neural…

Quantum Physics · Physics 2024-07-24 Naeimeh Mohseni , Junheng Shi , Tim Byrnes , Michael J. Hartmann

Interaction in quantum systems can spread initially localized quantum information into the many degrees of freedom of the entire system. Understanding this process, known as quantum scrambling, is the key to resolving various conundrums in…

Quantum Physics · Physics 2022-02-10 Xiao Mi , Pedram Roushan , Chris Quintana , Salvatore Mandra , Jeffrey Marshall , Charles Neill , Frank Arute , Kunal Arya , Juan Atalaya , Ryan Babbush , Joseph C. Bardin , Rami Barends , Andreas Bengtsson , Sergio Boixo , Alexandre Bourassa , Michael Broughton , Bob B. Buckley , David A. Buell , Brian Burkett , Nicholas Bushnell , Zijun Chen , Benjamin Chiaro , Roberto Collins , William Courtney , Sean Demura , Alan R. Derk , Andrew Dunsworth , Daniel Eppens , Catherine Erickson , Edward Farhi , Austin G. Fowler , Brooks Foxen , Craig Gidney , Marissa Giustina , Jonathan A. Gross , Matthew P. Harrigan , Sean D. Harrington , Jeremy Hilton , Alan Ho , Sabrina Hong , Trent Huang , William J. Huggins , L. B. Ioffe , Sergei V. Isakov , Evan Jeffrey , Zhang Jiang , Cody Jones , Dvir Kafri , Julian Kelly , Seon Kim , Alexei Kitaev , Paul V. Klimov , Alexander N. Korotkov , Fedor Kostritsa , David Landhuis , Pavel Laptev , Erik Lucero , Orion Martin , Jarrod R. McClean , Trevor McCourt , Matt McEwen , Anthony Megrant , Kevin C. Miao , Masoud Mohseni , Wojciech Mruczkiewicz , Josh Mutus , Ofer Naaman , Matthew Neeley , Michael Newman , Murphy Yuezhen Niu , Thomas E. O'Brien , Alex Opremcak , Eric Ostby , Balint Pato , Andre Petukhov , Nicholas Redd , Nicholas C. Rubin , Daniel Sank , Kevin J. Satzinger , Vladimir Shvarts , Doug Strain , Marco Szalay , Matthew D. Trevithick , Benjamin Villalonga , Theodore White , Z. Jamie Yao , Ping Yeh , Adam Zalcman , Hartmut Neven , Igor Aleiner , Kostyantyn Kechedzhi , Vadim Smelyanskiy , Yu Chen

We continue the study of the approximate $k$-wise independence of random reversible circuits as permutations of $\{\pm1\}^n$. Our main result is the first construction of a natural class of random reversible circuits with a sublinear-in-$n$…

Computational Complexity · Computer Science 2025-02-13 William Gay , William He , Nicholas Kocurek

A key conjecture about the evolution of complex quantum systems towards an ergodic steady state, known as scrambling, is that this process acquires universal features when it is most efficient. We develop a single-parameter scaling theory…

Quantum Physics · Physics 2025-03-05 Tara Kalsi , Alessandro Romito , Henning Schomerus

We define and construct efficient depth-universal and almost-size-universal quantum circuits. Such circuits can be viewed as general-purpose simulators for central classes of quantum circuits and can be used to capture the computational…

Computational Complexity · Computer Science 2008-04-16 Debajyoti Bera , Stephen Fenner , Frederic Green , Steve Homer

We consider random quantum circuits (RQC) on arbitrary connected graphs whose edges determine the allowed $2$-qudit interactions. Prior work has established that such $n$-qudit circuits with local dimension $q$ on 1D, complete, and…

Quantum Physics · Physics 2023-10-31 Shivan Mittal , Nicholas Hunter-Jones

Quantum error correction and symmetries play central roles in quantum information science and physics. It is known that quantum error-correcting codes covariant with respect to continuous symmetries cannot correct erasure errors perfectly…

Quantum Physics · Physics 2021-02-24 Linghang Kong , Zi-Wen Liu

A pure state of fixed Hamming weight is a superposition of computational basis states such that each bitstring in the superposition has the same number of ones. Given a Hilbert space of the form $\mathcal{H} = (\mathbb{C}_2)^{\otimes n}$,…

Quantum Physics · Physics 2025-01-22 Soorya Rethinasamy , Margarite L. LaBorde , Mark M. Wilde

Two prevalent approaches for preparing long-range entangled quantum states are (i) linear-depth sequential unitary (SU) circuits, which apply local unitary gates sequentially, and (ii) constant-depth measurement-feedback (MF) circuits,…

Quantum Physics · Physics 2025-07-18 Tsung-Cheng Lu , Sarang Gopalakrishnan , Yizhi You

A quantum system with a black hole accommodates two widely different, though physically equivalent, descriptions. In one description, based on global spacetime of general relativity, the existence of the interior region is manifest, while…

High Energy Physics - Theory · Physics 2021-03-24 Yasunori Nomura

In this work, we study distributions of unitaries generated by random quantum circuits containing only symmetry-respecting gates. We develop a unified approach applicable to all symmetry groups and obtain an equation that determines the…

Quantum Physics · Physics 2024-10-16 Hanqing Liu , Austin Hulse , Iman Marvian

We study the role of randomness in the scrambling of quantum information within integrable free-fermionic systems. Considering quadratic Hamiltonians with varying degrees of randomness, we analyze entanglement-based measures to characterize…

Quantum Physics · Physics 2025-11-11 Ali Mollabashi , Mohammad-Javad Vasli

Sampling unitary Fermionic Linear Optics (FLO), or matchgate circuits, has become a fundamental tool in quantum information. Such capability enables a large number of applications ranging from randomized benchmarking of continuous gate…

Quantum Physics · Physics 2025-06-02 Paolo Braccia , N. L. Diaz , Martin Larocca , M. Cerezo , Diego García-Martín

In large $N$ chaotic quantum systems, the butterfly effect is mediated by a collective field mode known as the ``scramblon.'' We study self-interactions of the scramblon in variants of the Sachdev-Ye-Kitaev model. In spatially extended…

High Energy Physics - Theory · Physics 2023-11-22 Douglas Stanford , Shreya Vardhan , Shunyu Yao

Recently a quantum portrait of black holes was suggested according to which a macroscopic black hole is a Bose-Einstein condensate of soft gravitons stuck at the critical point of a quantum phase transition. We explain why quantum…

High Energy Physics - Theory · Physics 2014-01-01 Gia Dvali , Daniel Flassig , Cesar Gomez , Alexander Pritzel , Nico Wintergerst

Quantum complexity is a measure of the minimal number of elementary operations required to approximately prepare a given state or unitary channel. Recently, this concept has found applications beyond quantum computing -- in studying the…

Quantum Physics · Physics 2025-01-22 Michał Oszmaniec , Marcin Kotowski , Michał Horodecki , Nicholas Hunter-Jones

Quantum spin rings represent an intriguing platform for studying unconventional magnetic order and exotic quantum phases, and they are also promising materials for emerging quantum technologies. Conventional spin systems consist of a set of…

We demonstrate that a high fidelity approximation to $| \Psi_b \rangle$, the quantum superposition over all bit strings within Hamming distance $b$ of the codewords of a dimension-$k$ linear code over $\mathbb{Z}_2^n$, can be efficiently…

Quantum Physics · Physics 2024-04-26 Edward Farhi , Stephen P. Jordan

Random quantum circuits have been utilized in the contexts of quantum supremacy demonstrations, variational quantum algorithms for chemistry and machine learning, and blackhole information. The ability of random circuits to approximate any…

Quantum Physics · Physics 2023-03-23 Minzhao Liu , Junyu Liu , Yuri Alexeev , Liang Jiang