Author(s): Zhifei Li and Daiqin Su

Concatenation of a bosonic code with a qubit code is one of the promising ways to achieve fault-tolerant quantum computation. As one of the most important bosonic codes, the Gottesman-Kitaev-Preskill (GKP) code is proposed to correct small displacement errors in phase space. If the noise in phase sp…

[Phys. Rev. A 109, 052420] Published Mon May 13, 2024

Author(s): Edoardo Centofanti, Paolo Perinotti, and Alessandro Bisio

We present a fermionic cellular automaton model which describes massless Dirac fermions in 1+1 dimension coupled with local, number preserving interaction. The diagonalization of the two particle sector shows that specific values of the total momentum and of the coupling constant allow for the forma…

[Phys. Rev. A 109, 052421] Published Mon May 13, 2024

Author(s): Xiao-Fan Zhen, Mao-Sheng Li, and Hui-Juan Zuo

Strong nonlocality, proposed by Halder *et al.* [Phys. Rev. Lett. **122**, 040403 (2019)], is a stronger manifestation than quantum nonlocality. Subsequently, Shi *et al.* presented the concept of the strongest nonlocality [Quantum **6**, 619 (2022)]. Recently, Li and Wang [Quantum **7**, 1101 (2023)] posed the con…

[Phys. Rev. A 109, 052422] Published Mon May 13, 2024

Author(s): Naoki Mitsuda, Tatsuhiro Ichimura, Kouhei Nakaji, Yohichi Suzuki, Tomoki Tanaka, Rudy Raymond, Hiroyuki Tezuka, Tamiya Onodera, and Naoki Yamamoto

Quantum computing has a potential to accelerate data processing efficiency, especially in machine learning, by exploiting special features such as the quantum interference. The major challenge in this application is that, in general, the task of loading a classical data vector into a quantum state r…

[Phys. Rev. A 109, 052423] Published Mon May 13, 2024

Author(s): Chandrashekhar Gaikwad, Daria Kowsari, Carson Brame, Xingrui Song, Haimeng Zhang, Martina Esposito, Arpit Ranadive, Giulio Cappelli, Nicolas Roch, Eli M. Levenson-Falk, and Kater W. Murch

We utilize a superconducting qubit processor to experimentally probe non-Markovian dynamics of an entangled qubit pair. We prepare an entangled state between two qubits and monitor the evolution of entanglement over time as one of the qubits interacts with a small quantum environment consisting of a…

[Phys. Rev. Lett. 132, 200401] Published Mon May 13, 2024

Author(s): Jung Hoon Han

In its superconducting state, an exotic metal harbors charge carriers that appear to have 4 and 6 times the charge of a single electron, suggesting the formation of Cooper-pair “molecules.”

[Physics 17, 80] Published Mon May 13, 2024

Categories: Physics

Author(s): Charles Day

The ability to store molecules in reconfigurable optical traps could allow researchers to harness the rich physics of molecules in quantum applications.

[Physics 17, s50] Published Mon May 13, 2024

Categories: Physics

Author(s): Yongdan Yang, Ying Li, Xiaosi Xu, and Xiao Yuan

Estimating the eigenvalue or energy gap of a Hamiltonian H is vital for studying quantum many-body systems. Particularly, many of the problems in quantum chemistry, condensed-matter physics, and nuclear physics investigate the energy gap between two eigenstates. Hence, how to efficiently solve the e…

[Phys. Rev. A 109, 052416] Published Fri May 10, 2024

Author(s): Andrea Rodriguez-Blanco, Farid Shahandeh, and Alejandro Bermudez

Quantum error correction (QEC) exploits redundancy by encoding logical information into multiple physical qubits. In current implementations of QEC, sequences of nonperfect two-qubit entangling gates are used to codify the information redundantly into multipartite entangled states. Also, to extract …

[Phys. Rev. A 109, 052417] Published Fri May 10, 2024

Author(s): Donghoon Ha and Jeong San Kim

We consider the discrimination of bipartite quantum states and establish a relation between a nonlocal quantum state ensemble and quantum data-hiding processing. Using a bound on the optimal local discrimination of bipartite quantum states, we provide a sufficient condition for a bipartite quantum s…

[Phys. Rev. A 109, 052418] Published Fri May 10, 2024

Author(s): Chao Yin, Andrew Lucas, and David T. Stephen

We bound the time necessary to implement the shift unitary on a one-dimensional ring, both by using local Hamiltonians and those with power-law interactions. This time is constrained by the Frobenius light cone; hence we prove that (for certain power-law exponents) shift unitaries cannot be implemen…

[Phys. Rev. A 109, 052419] Published Fri May 10, 2024

Author(s): Michael Schirber

Experiments show the effects on combustion of adding hydrogen to natural gas—a fuel mixture that could reduce carbon emissions from power plants.

[Physics 17, 79] Published Fri May 10, 2024

Categories: Physics

Author(s): Charles Day

X-ray experiments reveal that a semimetal exhibits “orbital texture”—an exotic electronic structure resulting in spin-dependent electron transport.

[Physics 17, s53] Published Fri May 10, 2024

Categories: Physics

Author(s): Hao-Nan Xie, Shi-Jie Wei, Fan Yang, Zheng-An Wang, Chi-Tong Chen, Heng Fan, and Gui-Lu Long

Imaginary-time evolution is a powerful tool in the study of quantum physics. However, existing classical algorithms for simulating imaginary-time evolution suffer from high computational complexity as the dimension of the quantum system increases. In this study we propose a quantum algorithm for imp…

[Phys. Rev. A 109, 052414] Published Thu May 09, 2024

Author(s): Nidhin Sudarsanan Ragini and Mario Ziman

We identify and study a particular class of distinguishability problems for quantum observables (positive-operator-valued measures), in which observables with permuted effects are involved, which we call the labeling problem. Consequently, we identify binary observables, which can be labeled perfect…

[Phys. Rev. A 109, 052415] Published Thu May 09, 2024

Author(s): Haiyang Qin, Liangyu Che, Chao Wei, Feng Xu, Yulei Huang, and Tao Xin

Fidelity estimation is an important technique for evaluating prepared quantum states in noisy quantum devices. A recent theoretical work proposed a frugal approach called neural quantum fidelity estimation (NQFE) [X. Zhang *et al.*, Phys. Rev. Lett. **127**, 130503 (2021).]. While this requires a much sm…

[Phys. Rev. Lett. 132, 190801] Published Thu May 09, 2024

Author(s): Charles Day

Adding neutrinos to an existing nucleosynthesis recipe can account for the puzzling existence of neutron-deficient heavy nuclei.

[Physics 17, s56] Published Thu May 09, 2024

Categories: Physics

Author(s): Raghav G. Jha, Felix Ringer, George Siopsis, and Shane Thompson

We formulate the O(3) nonlinear sigma model in 1+1 dimensions as a limit of a three-component scalar field theory restricted to the unit sphere in the large squeezing limit. This allows us to describe the model in terms of the continuous-variable (CV) approach to quantum computing. We construct the …

[Phys. Rev. A 109, 052412] Published Wed May 08, 2024

Author(s): Yu Luo, Fanxu Meng, and Youle Wang

The quantification of state-based quantum “resources” such as entanglement, coherence, and nonstabilizer states lies at the heart of quantum science and technology, providing potential advantages over classical methods. In a realistic scenario, due to the imperfections and uncertainties in physical …

[Phys. Rev. A 109, 052413] Published Wed May 08, 2024

Author(s): Jiangfeng Du, Fazhan Shi, Xi Kong, Fedor Jelezko, and Jörg Wrachtrup

Nitrogen-vacancy centers in diamond are sensitive to magnetic fields, and a single center permits detection of electron and nuclear spins and imaging of single molecules in its vicinity. This article reviews the achievements of advanced methods to obtain spectral and spatial resolution and it points to technical problems that remain to be solved for widespread and multidisciplinary adoption of single-molecule magnetic resonance spectroscopy.

[Rev. Mod. Phys. 96, 025001] Published Wed May 08, 2024