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Beating one bit of communication with and without quantum pseudo-telepathy npj Quantum Inform. (IF 6.6) Pub Date : 2024-08-22 István Márton, Erika Bene, Péter Diviánszky, Tamás Vértesi
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Classical-to-quantum non-signalling boxes Quantum (IF 5.1) Pub Date : 2024-08-22 Carolina Moreira Ferrera, Robin Simmons, James Purcell, Daniel Collins, Sandu Popescu
Here we introduce the concept of classical input – quantum output (C-Q) non-signalling boxes, a generalisation of the classical input – classical output (C-C) non-signalling boxes. We argue that studying such objects leads to a better understanding of the relation between quantum nonlocality and non-locality beyond quantum mechanics. The main issue discussed in the paper is whether there exist 'genuine'
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Taming Quantum Time Complexity Quantum (IF 5.1) Pub Date : 2024-08-23 Aleksandrs Belovs, Stacey Jeffery, Duyal Yolcu
Quantum query complexity has several nice properties with respect to composition. First, bounded-error quantum query algorithms can be composed without incurring log factors through error reduction $exactness$. Second, through careful accounting $thriftiness$, the total query complexity is smaller if subroutines are mostly run on cheaper inputs -- a property that is much less obvious in quantum algorithms
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Hybrid spin-orbit exciton-magnon excitations in FePS3 npj Quant. Mater. (IF 5.4) Pub Date : 2024-08-22 Ramesh Dhakal, Samuel Griffith, Stephen M. Winter
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Thermodynamic sensing of quantum nonlinear noise correlations Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-22 Nilakantha Meher, Tomáš Opatrný, Gershon Kurizki
We put forth the concept of quantum noise sensing in nonlinear two-mode interferometers coupled to mechanical oscillators. These autonomous machines are capable of sensing quantum nonlinear correlations of two-mode noisy fields via their thermodynamic variable of extractable work, alias work capacity (WC) or ergotropy. The fields are formed by thermal noise input via its interaction with multi-level
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Photonic variational quantum eigensolver using entanglement measurements Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-21 Jinil Lee, Wooyeong Song, Donghwa Lee, Yosep Kim, Seung-Woo Lee, Hyang-Tag Lim, Hojoong Jung, Sang-Wook Han, Yong-Su Kim
Variational quantum eigensolver (VQE), which combines quantum systems with classical computational power, has been arisen as a promising candidate for near-term quantum computing applications. However, the experimental resources such as the number of measurements to implement VQE rapidly increases as the Hamiltonian problem size grows. Applying entanglement measurements to reduce the number of measurement
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Unraveling magneto-elastoresistance in the Dirac nodal-line semi-metal ZrSiSe npj Quant. Mater. (IF 5.4) Pub Date : 2024-08-20 J. F. Linnartz, A. Kool, J. P. Lorenz, C. S. A. Müller, M. R. van Delft, R. Singha, L. M. Schoop, N. E. Hussey, A. de Visser, S. Wiedmann
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Entanglement-preserving measurement of the Bell parameter on a single entangled pair Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-20 Salvatore Virzì, Enrico Rebufello, Francesco Atzori, Alessio Avella, Fabrizio Piacentini, Rudi Lussana, Iris Cusini, Francesca Madonini, Federica Villa, Marco Gramegna, Eliahu Cohen, Ivo Pietro Degiovanni, Marco Genovese
Bell inequalities represent one of the cornerstones of quantum foundations, and a fundamental tool for quantum technologies. Although a lot of effort was put in exploring and generalizing them, because of the wave function collapse it was deemed impossible to estimate the entire Bell parameter from one entangled pair, since this would involve measuring incompatible observables on the same quantum state
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Gauge field dynamics in multilayer Kitaev spin liquids npj Quant. Mater. (IF 5.4) Pub Date : 2024-08-18 Aprem P. Joy, Achim Rosch
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Certification of quantum state functions under partial information Quantum (IF 5.1) Pub Date : 2024-08-16 Leonardo Zambrano, Donato Farina, Egle Pagliaro, Marcio M. Taddei, Antonio Acin
Convex functions of quantum states play a key role in quantum physics, with examples ranging from Bell inequalities to von Neumann entropy. However, in experimental scenarios, direct measurements of these functions are often impractical. We address this issue by introducing two methods for determining rigorous confidence bounds for convex functions based on informationally incomplete measurements.
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High-TC superconductivity in La3Ni2O7 based on the bilayer two-orbital t-J model npj Quant. Mater. (IF 5.4) Pub Date : 2024-08-13 Zhihui Luo, Biao Lv, Meng Wang, Wéi Wú, Dao-Xin Yao
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Mitigation of interfacial dielectric loss in aluminum-on-silicon superconducting qubits npj Quantum Inform. (IF 6.6) Pub Date : 2024-08-14 Janka Biznárová, Amr Osman, Emil Rehnman, Lert Chayanun, Christian Križan, Per Malmberg, Marcus Rommel, Christopher Warren, Per Delsing, August Yurgens, Jonas Bylander, Anita Fadavi Roudsari
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Coherence of a field gradient driven singlet-triplet qubit coupled to multielectron spin states in 28Si/SiGe npj Quantum Inform. (IF 6.6) Pub Date : 2024-08-14 Younguk Song, Jonginn Yun, Jehyun Kim, Wonjin Jang, Hyeongyu Jang, Jaemin Park, Min-Kyun Cho, Hanseo Sohn, Noritaka Usami, Satoru Miyamoto, Kohei M. Itoh, Dohun Kim
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Enhancing the electron pair approximation with measurements on trapped-ion quantum computers npj Quantum Inform. (IF 6.6) Pub Date : 2024-08-13 Luning Zhao, Qingfeng Wang, Joshua J. Goings, Kyujin Shin, Woomin Kyoung, Seunghyo Noh, Young Min Rhee, Kyungmin Kim
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Approximate Quantum Codes From Long Wormholes Quantum (IF 5.1) Pub Date : 2024-08-14 Gregory Bentsen, Phuc Nguyen, Brian Swingle
We discuss families of approximate quantum error correcting codes which arise as the nearly-degenerate ground states of certain quantum many-body Hamiltonians composed of non-commuting terms. For exact codes, the conditions for error correction can be formulated in terms of the vanishing of a two-sided mutual information in a low-temperature thermofield double state. We consider a notion of distance
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Quantum Reference Frames for Lorentz Symmetry Quantum (IF 5.1) Pub Date : 2024-08-14 Luca Apadula, Esteban Castro-Ruiz, Časlav Brukner
Since their first introduction, Quantum Reference Frame (QRF) transformations have been extensively discussed, generalising the covariance of physical laws to the quantum domain. Despite important progress, a formulation of QRF transformations for Lorentz symmetry is still lacking. The present work aims to fill this gap. We first introduce a reformulation of relativistic quantum mechanics independent
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Study of noise in virtual distillation circuits for quantum error mitigation Quantum (IF 5.1) Pub Date : 2024-08-14 Pontus Vikstål, Giulia Ferrini, Shruti Puri
Virtual distillation has been proposed as an error mitigation protocol for estimating the expectation values of observables in quantum algorithms. It proceeds by creating a cyclic permutation of $M$ noisy copies of a quantum state using a sequence of controlled-swap gates. If the noise does not shift the dominant eigenvector of the density operator away from the ideal state, then the error in expectation-value
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Excellent thermoelectric performance of Fe2NbAl alloy induced by strong crystal anharmonicity and high band degeneracy npj Quant. Mater. (IF 5.4) Pub Date : 2024-08-13 Xianfeng Ye, Jian Yu, Shaoqiu Ke, Dong Liang, Tiantian Chen, Chengshan Liu, Wenjie Xu, Longzhou Li, Wanting Zhu, Xiaolei Nie, Ping Wei, Wenyu Zhao, Qingjie Zhang
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Loss-induced quantum nonreciprocity npj Quantum Inform. (IF 6.6) Pub Date : 2024-08-12 Baijun Li, Yunlan Zuo, Le-Man Kuang, Hui Jing, Chaohong Lee
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Non-Markovianity in High-Dimensional Open Quantum Systems using Next-generation Multicore Optical Fibers Quantum (IF 5.1) Pub Date : 2024-08-12 Santiago Rojas-Rojas, Daniel Martínez, Kei Sawada, Luciano Pereira, Stephen P. Walborn, Esteban S. Gómez, Nadja K. Bernardes, Gustavo Lima
With the advent of quantum technology, the interest in communication tasks assisted by quantum systems has increased both in academia and industry. Nonetheless, the transmission of a quantum state in real-world scenarios is bounded by environmental noise, so that the quantum channel is an open quantum system. In this work, we study a high-dimensional open quantum system in a multicore optical fiber
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Maximum expectation of observables with restricted purity states Quantum (IF 5.1) Pub Date : 2024-08-13 Vikesh Siddhu, John Aaron Smolin
Assessment of practical quantum information processing (QIP) remains partial without understanding limits imposed by noise. Unfortunately, mere description of noise grows exponentially with system size, becoming cumbersome even for modest sized systems of imminent practical interest. We fulfill the need for estimates on performing noisy quantum state preparation, verification, and observation. To do
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Measurement-efficient quantum Krylov subspace diagonalisation Quantum (IF 5.1) Pub Date : 2024-08-13 Zongkang Zhang, Anbang Wang, Xiaosi Xu, Ying Li
The Krylov subspace methods, being one category of the most important classical numerical methods for linear algebra problems, can be much more powerful when generalised to quantum computing. However, quantum Krylov subspace algorithms are prone to errors due to inevitable statistical fluctuations in quantum measurements. To address this problem, we develop a general theoretical framework to analyse
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A differentiable quantum phase estimation algorithm Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-13 Davide Castaldo, Soran Jahangiri, Agostino Migliore, Juan Miguel Arrazola, Stefano Corni
The simulation of electronic properties is a pivotal issue in modern electronic structure theory, driving significant efforts over the past decades to develop protocols for computing energy derivatives. In this work, we address this problem by developing a strategy to integrate the quantum phase estimation algorithm within a fully differentiable framework. This is accomplished by devising a smooth
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A square-root speedup for finding the smallest eigenvalue Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-12 Alex Kerzner, Vlad Gheorghiu, Michele Mosca, Thomas Guilbaud, Federico Carminati, Fabio Fracas, Luca Dellantonio
We describe a quantum algorithm for finding the smallest eigenvalue of a Hermitian matrix. This algorithm combines quantum phase estimation and quantum amplitude estimation to achieve a quadratic speedup with respect to the best classical algorithm in terms of matrix dimensionality, i.e. O~(N/ε) 9 9In this work O~ ignores terms that are polylogarithmic in N or 1/ε . black-box queries to an oracle encoding
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Majorana modes in striped two-dimensional inhomogeneous topological superconductors npj Quant. Mater. (IF 5.4) Pub Date : 2024-08-10 Pasquale Marra, Daisuke Inotani, Takeshi Mizushima, Muneto Nitta
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Information compression via hidden subgroup quantum autoencoders npj Quantum Inform. (IF 6.6) Pub Date : 2024-08-08 Feiyang Liu, Kaiming Bian, Fei Meng, Wen Zhang, Oscar Dahlsten
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Scalable determination of multipartite entanglement in quantum networks npj Quantum Inform. (IF 6.6) Pub Date : 2024-08-08 Wei-Ting Kao, Chien-Ying Huang, Tung-Ju Tsai, Shih-Hsuan Chen, Sheng-Yan Sun, Yu-Cheng Li, Teh-Lu Liao, Chih-Sung Chuu, He Lu, Che-Ming Li
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A learning theory for quantum photonic processors and beyond Quantum (IF 5.1) Pub Date : 2024-08-08 Matteo Rosati
We consider the tasks of learning quantum states, measurements and channels generated by continuous-variable (CV) quantum circuits. This family of circuits is suited to describe optical quantum technologies and in particular it includes state-of-the-art photonic processors capable of showing quantum advantage. We define classes of functions that map classical variables, encoded into the CV circuit
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Hayden-Preskill recovery in chaotic and integrable unitary circuit dynamics Quantum (IF 5.1) Pub Date : 2024-08-08 Michael A. Rampp, Pieter W. Claeys
The Hayden-Preskill protocol probes the capability of information recovery from local subsystems after unitary dynamics. As such it resolves the capability of quantum many-body systems to dynamically implement a quantum error-correcting code. The transition to coding behavior has been mostly discussed using effective approaches, such as entanglement membrane theory. Here, we present exact results on
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Resource-Efficient Real-Time Polarization Compensation for MDI-QKD with Rejected Data Quantum (IF 5.1) Pub Date : 2024-08-08 Olinka Bedroya, Chenyang Li, Wenyuan Wang, Jianyong Hu, Hoi-Kwong Lo, Li Qian
Measurement-device-independent quantum key distribution (MDI-QKD) closes all the security loopholes in the detection system and is a promising solution for secret key sharing. Polarization encoding is the most common QKD encoding scheme, as it is straightforward to prepare and measure. However, implementing polarization encoding in MDI QKD imposes extra challenges, as polarization alignment must be
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Ratchet loading and multi-ensemble operation in an optical lattice clock Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-08 Youssef S Hassan, Takumi Kobayashi, Tobias Bothwell, Jacob L Seigel, Benjamin D Hunt, Kyle Beloy, Kurt Gibble, Tanner Grogan, Andrew D Ludlow
We demonstrate programmable control over the spatial distribution of ultra-cold atoms confined in an optical lattice. The control is facilitated through a combination of spatial manipulation of the magneto-optical trap and atomic population shelving to a metastable state. We first employ the technique to load an extended (5 mm) atomic sample with uniform density in an optical lattice clock (OLC), reducing
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Bang-bang optimal control in coherent spin dynamics of radical pairs in quantum biology Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-08 Ugur G Abdulla, Jose Rodrigues, Pablo Jimenez, Chenming Zhen, Carlos Martino
Optimal control of the external electromagnetic field input for the maximization of the quantum triplet-singlet yield of the radical pairs in biochemical reactions modeled by Schrödinger system with spin Hamiltonians given by the sum of Zeeman interaction and hyperfine coupling interaction terms are analyzed. Fréchet differentiability and Pontryagin Maximum Principle in Hilbert space is proved and
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Optimal and robust quantum state tomography of star-topology register Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-08 Ran Liu, Yanjun Hou, Ze Wu, Hui Zhou, Jiahui Chen, Zhaokai Li, Xinhua Peng
While quantum state tomography plays a vital role in the verification and benchmarking of quantum systems, it is an intractable task if the controllability of the quantum registers is constrained. In this paper, we propose a novel scheme for optimal and robust quantum state tomography for systems with constrained controllability. Based on the specific symmetry, we decompose the Hilbert space to alleviate
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Entanglement spectrum of matchgate circuits with universal and non-universal resources Quantum (IF 5.1) Pub Date : 2024-08-07 Andrew M. Projansky, Joshuah T. Heath, James D. Whitfield
The entanglement level statistics of a quantum state have recently been proposed to be a signature of universality in the underlying quantum circuit. This is a consequence of level repulsion in the entanglement spectra being tied to the integrability of entanglement generated. However, such studies of the level-spacing statistics in the entanglement spectrum have thus far been limited to the output
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Distributing circuits over heterogeneous, modular quantum computing network architectures Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-06 Pablo Andres-Martinez, Tim Forrer, Daniel Mills, Jun-Yi Wu, Luciana Henaut, Kentaro Yamamoto, Mio Murao, Ross Duncan
We consider a heterogeneous network of quantum computing modules, sparsely connected via Bell states. Operations across these connections constitute a computational bottleneck and they are likely to add more noise to the computation than operations performed within a module. We introduce several techniques for transforming a given quantum circuit into one implementable on such a network, minimising
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Improved Pairwise Measurement-Based Surface Code Quantum (IF 5.1) Pub Date : 2024-08-02 Linnea Grans-Samuelsson, Ryan V. Mishmash, David Aasen, Christina Knapp, Bela Bauer, Brad Lackey, Marcus P. da Silva, Parsa Bonderson
We devise a new realization of the surface code on a rectangular lattice of qubits utilizing single-qubit and nearest-neighbor two-qubit Pauli measurements and three auxiliary qubits per plaquette. This realization gains substantial advantages over prior pairwise measurement-based realizations of the surface code. It has a short operation period of 4 steps and our performance analysis for a standard
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Stabilization of symmetry-protected long-range entanglement in stochastic quantum circuits Quantum (IF 5.1) Pub Date : 2024-08-02 Iosifina Angelidi, Marcin Szyniszewski, Arijeet Pal
Long-range entangled states are vital for quantum information processing and quantum metrology. Preparing such states by combining measurements with unitary gates opened new possibilities for efficient protocols with finite-depth quantum circuits. The complexity of these algorithms is crucial for the resource requirements on a large-scale noisy quantum device, while their stability to perturbations
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Long-lived collective Rydberg excitations in atomic gas achieved via ac-Stark lattice modulation Quantum (IF 5.1) Pub Date : 2024-08-02 Stanisław Kurzyna, Bartosz Niewelt, Mateusz Mazelanik, Wojciech Wasilewski, Michał Parniak
Collective Rydberg excitations provide promising applications ranging from quantum information processing, and quantum computing to ultra-sensitive electrometry. However, their short lifetime is an immense obstacle in real-life scenarios. The state-of-the-art methods of prolonging the lifetime were mainly implemented for ground-state quantum memories and would require a redesign to effectively work
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Experimental realization of active nonlinear feedback control from hot rubidium vapor Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-02 Xiaozhou Pan, Tianxiang Wei, Kai Zhang, Jietai Jing
Feedback control plays a crucial role in preparation and manipulation of quantum states, to evolve the quantum system towards a desired result. Here we report a novel feedback control system utilizing two four-wave mixing (FWM) processes, in which the first FWM process functions as an amplifier while the second FWM process serves as an active nonlinear controller. We experimentally investigate the
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Emergence of noise-induced barren plateaus in arbitrary layered noise models Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-02 M Schumann, F K Wilhelm, A Ciani
In variational quantum algorithms the parameters of a parameterized quantum circuit are optimized in order to minimize a cost function that encodes the solution of the problem. The barren plateau phenomenon manifests as an exponentially vanishing dependence of the cost function with respect to the variational parameters, and thus hampers the optimization process. We discuss how, and in which sense
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Conditional quantum thermometry—enhancing precision by measuring less Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-02 Akira Sone, Diogo O Soares-Pinto, Sebastian Deffner
Taking accurate measurements of the temperature of quantum systems is a challenging task. The mathematical peculiarities of quantum information make it virtually impossible to measure with infinite precision. In the present paper, we introduce a generalize thermal state, which is conditioned on the pointer states of the available measurement apparatus. We show that this conditional thermal state outperforms
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Nonequilibrium fluctuations of a quantum heat engine Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-01 Tobias Denzler, Jonas F G Santos, Eric Lutz, Roberto M Serra
The thermodynamic properties of quantum heat engines are stochastic owing to the presence of thermal and quantum fluctuations. We here experimentally investigate the efficiency and nonequilibrium entropy production statistics of a spin-1/2 quantum Otto cycle in a nuclear magnetic resonance setup. We first study the correlations between work and heat within a cycle by extracting their joint distribution
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Integer programming using a single atom Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-08-01 Kapil Goswami, Peter Schmelcher, Rick Mukherjee
Integer programming (IP), as the name suggests is an integer-variable-based approach commonly used to formulate real-world optimization problems with constraints. Currently, quantum algorithms reformulate the IP into an unconstrained form through the use of binary variables, which is an indirect and resource-consuming way of solving it. We develop an algorithm that maps and solves an IP problem in
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Universal framework for simultaneous tomography of quantum states and SPAM noise Quantum (IF 5.1) Pub Date : 2024-07-30 Abhijith Jayakumar, Stefano Chessa, Carleton Coffrin, Andrey Y. Lokhov, Marc Vuffray, Sidhant Misra
We present a general denoising algorithm for performing $\textit{simultaneous tomography}$ of quantum states and measurement noise. This algorithm allows us to fully characterize state preparation and measurement (SPAM) errors present in any quantum system. Our method is based on the analysis of the properties of the linear operator space induced by unitary operations. Given any quantum system with
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Single-shot Quantum Signal Processing Interferometry Quantum (IF 5.1) Pub Date : 2024-07-30 Jasmine Sinanan-Singh, Gabriel L. Mintzer, Isaac L. Chuang, Yuan Liu
Quantum systems of infinite dimension, such as bosonic oscillators, provide vast resources for quantum sensing. Yet, a general theory on how to manipulate such bosonic modes for sensing beyond parameter estimation is unknown. We present a general algorithmic framework, quantum signal processing interferometry (QSPI), for quantum sensing at the fundamental limits of quantum mechanics by generalizing
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Adiabatic quantum trajectories in engineered reservoirs Quantum (IF 5.1) Pub Date : 2024-07-30 Emma C. King, Luigi Giannelli, Raphaël Menu, Johannes N. Kriel, Giovanna Morigi
We analyze the efficiency of protocols for adiabatic quantum state transfer assisted by an engineered reservoir. The target dynamics is a quantum trajectory in the Hilbert space and is a fixed point of a time-dependent master equation in the limit of adiabatic dynamics. We specialize to quantum state transfer in a qubit and determine the optimal schedule for a class of time-dependent Lindblad equations
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Multiferroic quantum material Ba2Cu1−xMnxGe2O7 (0 ≤ x ≤ 1) as a potential candidate for frustrated Heisenberg antiferromagnet npj Quant. Mater. (IF 5.4) Pub Date : 2024-07-29 Henrik Thoma, Rajesh Dutta, Vladimir Hutanu, Veronica Granata, Rosalba Fittipaldi, Qiang Zhang, Jeffrey W. Lynn, Petr Čermák, Nazir Khan, Shibabrata Nandi, Manuel Angst
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On Strong Bounds for Trotter and Zeno Product Formulas with Bosonic Applications Quantum (IF 5.1) Pub Date : 2024-07-25 Tim Möbus
The Trotter product formula and the quantum Zeno effect are both indispensable tools for constructing time-evolutions using experimentally feasible building blocks. In this work, we discuss assumptions under which quantitative bounds can be proven in the strong operator topology on Banach spaces and provide natural bosonic examples. Specially, we assume the existence of a continuously embedded Banach
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Privacy-preserving machine learning with tensor networks Quantum (IF 5.1) Pub Date : 2024-07-25 Alejandro Pozas-Kerstjens, Senaida Hernández-Santana, José Ramón Pareja Monturiol, Marco Castrillón López, Giannicola Scarpa, Carlos E. González-Guillén, David Pérez-García
Tensor networks, widely used for providing efficient representations of low-energy states of local quantum many-body systems, have been recently proposed as machine learning architectures which could present advantages with respect to traditional ones. In this work we show that tensor-network architectures have especially prospective properties for privacy-preserving machine learning, which is important
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A Spin-Optical Quantum Computing Architecture Quantum (IF 5.1) Pub Date : 2024-07-24 Grégoire de Gliniasty, Paul Hilaire, Pierre-Emmanuel Emeriau, Stephen C. Wein, Alexia Salavrakos, Shane Mansfield
We introduce an adaptable and modular hybrid architecture designed for fault-tolerant quantum computing. It combines quantum emitters and linear-optical entangling gates to leverage the strength of both matter-based and photonic-based approaches. A key feature of the architecture is its practicality, grounded in the utilisation of experimentally proven optical components. Our framework enables the
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Counterfactuality, back-action, and information gain in multi-path interferometers Quantum Sci. Technol. (IF 5.6) Pub Date : 2024-07-24 Jonte R Hance, Tomonori Matsushita, Holger F Hofmann
The presence of an absorber in one of the paths of an interferometer changes the output statistics of that interferometer in a fundamental manner. Since the individual quantum particles detected at any of the outputs of the interferometer have not been absorbed, any non-trivial effect of the absorber on the distribution of these particles over these paths is a counterfactual effect. Here, we quantify
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The silicon vacancy centers in SiC: determination of intrinsic spin dynamics for integrated quantum photonics npj Quantum Inform. (IF 6.6) Pub Date : 2024-07-23 Di Liu, Florian Kaiser, Vladislav Bushmakin, Erik Hesselmeier, Timo Steidl, Takeshi Ohshima, Nguyen Tien Son, Jawad Ul-Hassan, Öney O. Soykal, Jörg Wrachtrup
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Fundamental causal bounds of quantum random access memories npj Quantum Inform. (IF 6.6) Pub Date : 2024-07-23 Yunfei Wang, Yuri Alexeev, Liang Jiang, Frederic T. Chong, Junyu Liu
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Zero and Finite Temperature Quantum Simulations Powered by Quantum Magic Quantum (IF 5.1) Pub Date : 2024-07-23 Andi Gu, Hong-Ye Hu, Di Luo, Taylor L. Patti, Nicholas C. Rubin, Susanne F. Yelin
We introduce a quantum information theory-inspired method to improve the characterization of many-body Hamiltonians on near-term quantum devices. We design a new class of similarity transformations that, when applied as a preprocessing step, can substantially simplify a Hamiltonian for subsequent analysis on quantum hardware. By design, these transformations can be identified and applied efficiently
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Classical product code constructions for quantum Calderbank-Shor-Steane codes Quantum (IF 5.1) Pub Date : 2024-07-22 Dimiter Ostrev, Davide Orsucci, Francisco Lázaro, Balazs Matuz
Several notions of code products are known in quantum error correction, such as hypergraph products, homological products, lifted products, balanced products, to name a few. In this paper we introduce a new product code construction which is a natural generalization of classical product codes to quantum codes: starting from a set of component Calderbank-Shor-Steane (CSS) codes, a larger CSS code is
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Learning quantum phases via single-qubit disentanglement Quantum (IF 5.1) Pub Date : 2024-07-22 Zheng An, Chenfeng Cao, Cheng-Qian Xu, D. L. Zhou
Identifying phases of matter presents considerable challenges, particularly within the domain of quantum theory, where the complexity of ground states appears to increase exponentially with system size. Quantum many-body systems exhibit an array of complex entanglement structures spanning distinct phases. Although extensive research has explored the relationship between quantum phase transitions and
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Cr doping-induced ferromagnetism in SnTe thin films npj Quant. Mater. (IF 5.4) Pub Date : 2024-07-21 Shanshan Liu, Enze Zhang, Zihan Li, Xiaoqian Zhang, Wenqing Liu, Awadhesh Narayan, Zhi-Gang Chen, Jin Zou, Faxian Xiu
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Anomalous upper critical field in the quasicrystal superconductor Ta1.6Te npj Quant. Mater. (IF 5.4) Pub Date : 2024-07-20 Taichi Terashima, Yuki Tokumoto, Kotaro Hamano, Takako Konoike, Naoki Kikugawa, Keiichi Edagawa
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Spin and lattice dynamics of the two-dimensional van der Waals ferromagnet CrI3 npj Quant. Mater. (IF 5.4) Pub Date : 2024-07-20 Jonghyeon Kim, Saikat Banerjee, Junghyun Kim, Minseong Lee, Suhan Son, Jangwon Kim, Taek Sun Jung, Kyung Ik Sim, Je-Geun Park, Jae Hoon Kim
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Network quantum steering enables randomness certification without seed randomness Quantum (IF 5.1) Pub Date : 2024-07-19 Shubhayan Sarkar
Quantum networks with multiple sources allow the observation of quantum nonlocality without inputs. Consequently, the incompatibility of measurements is not a necessity for observing quantum nonlocality when one has access to multiple quantum sources. Here we investigate the minimal scenario without inputs where one can observe any form of quantum nonlocality. We show that even two parties with two