English
Related papers

Related papers: Shallow quantum circuit for generating extremely l…

200 papers

Predicting features of complex, large-scale quantum systems is essential to the characterization and engineering of quantum architectures. We present an efficient approach for constructing an approximate classical description, called the…

Quantum Physics · Physics 2019-11-26 Hsin-Yuan Huang , Richard Kueng

We present an efficient algorithm for twirling a multi-qudit quantum state. The algorithm can be used for approximating the twirling operation in an ensemble of physical systems in which the systems cannot be individually accessed. It can…

Quantum Physics · Physics 2007-05-23 Geza Toth , Juan Jose Garcia-Ripoll

Quantum fingerprinting is a technique that maps classical input word to a quantum state. The obtained quantum state is much shorter than the original word, and its processing uses less resources, making it useful in quantum algorithms,…

Quantum Physics · Physics 2025-05-20 Mansur Ziiatdinov , Aliya Khadieva , Kamil Khadiev

The computational power of real-world quantum computers is limited by errors. When using quantum computers to perform algorithms which cannot be efficiently simulated classically, it is important to quantify the accuracy with which the…

Quantum Physics · Physics 2024-01-18 Avi Vadali , Rutuja Kshirsagar , Prasanth Shyamsundar , Gabriel N. Perdue

We address the question of efficient implementation of quantum protocols, with small communication and entanglement, and short depth circuit for encoding or decoding. We introduce two new methods to achieve this, the first method involving…

Quantum Physics · Physics 2022-08-23 Anurag Anshu , Rahul Jain

It is generally believed that entanglement is essential for quantum computing. We present here a few simple examples in which quantum computing without entanglement is better than anything classically achievable, in terms of the reliability…

Quantum Physics · Physics 2007-05-23 Eli Biham , Gilles Brassard , Dan Kenigsberg , Tal Mor

Here we present an efficient quantum algorithm to generate an equivalent many-body state to Laughlin's $\nu=1/3$ fractional quantum Hall state on a digitized quantum computer. Our algorithm only uses quantum gates acting on neighboring…

Strongly Correlated Electrons · Physics 2020-11-10 Armin Rahmani , Kevin J. Sung , Harald Putterman , Pedram Roushan , Pouyan Ghaemi , Zhang Jiang

We prove that random quantum circuits on any geometry, including a 1D line, can form approximate unitary designs over $n$ qubits in $\log n$ depth. In a similar manner, we construct pseudorandom unitaries (PRUs) in 1D circuits in…

Quantum Physics · Physics 2025-01-07 Thomas Schuster , Jonas Haferkamp , Hsin-Yuan Huang

The classical shadows protocol is an efficient strategy for estimating properties of an unknown state $\rho$ using a small number of state copies and measurements. In its original form, it involves twirling the state with unitaries from…

Quantum Physics · Physics 2024-01-23 Pierre-Gabriel Rozon , Ning Bao , Kartiek Agarwal

Entanglement is a quantum resource, in some ways analogous to randomness in classical computation. Inspired by recent work of Gheorghiu and Hoban, we define the notion of "pseudoentanglement'', a property exhibited by ensembles of…

We investigate the generation of quantum states for precision metrology in noisy two-level systems. These states are obtained by optimizing a variational quantum circuit to maximize the quantum Fisher information (QFI) of the output state…

We present a construction of genuinely entangled multipartite quantum states based on the group theory. Analyzed states resemble the Dicke states, whereas the interactions occur only between specific subsystems related by the action of the…

Quantum Physics · Physics 2021-09-01 Adam Burchardt , Jakub Czartowski , Karol Życzkowski

Dynamic quantum circuits (DQCs) incorporate mid-circuit measurements and gates conditioned on these measurement outcomes. DQCs can prepare certain long-range entangled states in constant depth, making them a promising route to preparing…

Quantum Physics · Physics 2024-10-14 Faisal Alam , Bryan K. Clark

As we continue to find applications where the currently available noisy devices exhibit an advantage over their classical counterparts, the efficient use of quantum resources is highly desirable. The notion of quantum autoencoders was…

Quantum Physics · Physics 2022-07-08 Abhinav Anand , Jakob S. Kottmann , Alán Aspuru-Guzik

We study the encoding complexity for quantum error correcting codes with large rate and distance. We prove that random Clifford circuits with $O(n \log^2 n)$ gates can be used to encode $k$ qubits in $n$ qubits with a distance $d$ provided…

Quantum Physics · Physics 2013-12-31 Winton Brown , Omar Fawzi

Previous theoretical works showed that all pure two-qubit entangled states can generate one bit of local randomness and can be self-tested through the violation of proper Bell inequalities. We report an experiment in which nearly pure…

Quantum Physics · Physics 2019-03-14 S. Gómez , A. Mattar , I. Machuca , E. S. Gómez , D. Cavalcanti , O. Jiménez Farías , A. Acín , G. Lima

Quantum graph state is a special class of nonlocal state among multiple quantum particles, underpinning several nonclassical and promising applications such as quantum computing and quantum secret sharing. Recently, establishing quantum…

Quantum Physics · Physics 2025-08-14 Tingxiang Ji , Jianqing Liu , Zheshen Zhang

Entanglement is recognized as a key resource for quantum computation and quantum cryptography. For quantum metrology, the use of entangled states has been discussed and demonstrated as a means of improving the signal-to-noise ratio. In…

Quantum Physics · Physics 2007-05-23 C. F. Roos , M. Chwalla , K. Kim , M. Riebe , R. Blatt

We develop Monte Carlo methods for sampling random states and corresponding bit strings in qubit systems. To this end, we derive exact probability density functions that yield the Porter-Thomas distribution in the limit of large systems. We…

Quantum Physics · Physics 2025-09-05 Andreas Raab

We introduce a general statistical learning theory for processes that take as input a classical random variable and output a quantum state. Our setting is motivated by the practical situation in which one desires to learn a quantum process…

Quantum Physics · Physics 2025-02-27 Marco Fanizza , Yihui Quek , Matteo Rosati