QUROPE Quantum Information Processing and Communication in Europe

Author(s): Pedro S. Correia, Gabriel Dias Carvalho, Thiago R. de Oliveira, Raúl O. Vallejos, and Fernando de Melo

With the control of increasingly complex quantum systems, the relevant degrees of freedom we are interested in may not be those traditionally addressed by statistical quantum mechanics. Here, we employ quantum channels to define generalized subsystems, capturing the pertinent degrees of freedom, and…

[Phys. Rev. Lett. 133, 060401] Published Wed Aug 07, 2024

Author(s): R. Benevides, M. Drimmer, G. Bisson, F. Adinolfi, U. v. Lüpke, H. M. Doeleman, G. Catelani, and Y. Chu

A known source of decoherence in superconducting qubits is the presence of broken Cooper pairs, or quasiparticles. These can be generated by high-energy radiation, either present in the environment or purposefully introduced, as in the case of some hybrid quantum devices. Here, we systematically stu…

[Phys. Rev. Lett. 133, 060602] Published Wed Aug 07, 2024

Author(s): Sumner N. Hearth, Michael O. Flynn, Anushya Chandran, and Chris R. Laumann

Shadow tomography aims to build a classical description of a quantum state from a sequence of simple random measurements. Physical observables are then reconstructed from the resulting classical shadow. Shadow protocols which use single-body random measurements are simple to implement and capture fe…

[Phys. Rev. Lett. 133, 060802] Published Wed Aug 07, 2024

Author(s): Charles Day

A resonance between energy levels in argon atoms and nitrogen molecules could be used to remotely sense contaminants in air.

[Physics 17, s88] Published Wed Aug 07, 2024

Author(s): Chellasamy Jebarathinam, Gautam Sharma, Sk Sazim, and Remigiusz Augusiak

Self-testing of quantum devices based on observed measurement statistics is a method to certify quantum systems using minimal resources. In Irfan et al. [A. A. M. Irfan, K. Mayer, G. Ortiz, and E. Knill, Phys. Rev. A 101, 032106 (2020)] a scheme based on observing measurement statistics that demonst…

[Phys. Rev. A 110, 022408] Published Tue Aug 06, 2024

Author(s): F. E. S. Steinhoff

The states generated by a multiport beam splitter usually display genuine multipartite entanglement between the many spatial modes. Here we investigate the different classes of multipartite entangled states that arise in this practical situation, working within the paradigm of stochastic local opera…

[Phys. Rev. A 110, 022409] Published Tue Aug 06, 2024

Author(s): Detlef Lohse and Olga Shishkina

Rayleigh-Bénard convection is the flow in a closed box heated from below and cooled from above. The ultimate regime of Rayleigh-Bapos{e}nard turbulence occurs when the dimensionless temperature difference between the bottom and top plates is large. This review gives a comprehensive overview of the theoretical approaches to the ultimate regime and of the experimental and numerical results on the transition to this regime. These are reconciled by realizing that the transition is of non-normal–nonlinear nature, as typical for the laminar to turbulent transition in shear flow. The review also suggests experimental and numerical approaches to further understand the transition to the ultimate regime.

[Rev. Mod. Phys. 96, 035001] Published Tue Aug 06, 2024

Author(s): Yu Tao, Xinhang Li, Lang Li, Jingzheng Huang, Hongjing Li, Tao Wang, Linjie Zhou, and Guihua Zeng

Bosonic loss estimation has an important role in quantum metrology. It was once believed that the ultimate precision of this task is restricted to the standard quantum limit if no quantum probe is involved. Nevertheless, a recent proposal showed that this limit can be surpassed by utilizing ring res…

[Phys. Rev. Lett. 133, 060801] Published Tue Aug 06, 2024

Author(s): Ryan Wilkinson

Researchers have used a specially crafted electric potential to manipulate the electronic band structure of graphene, laying the groundwork for on-demand electronic band design.

[Physics 17, s92] Published Tue Aug 06, 2024

Author(s): Kaiming Bian, Shitao Zhang, Fei Meng, Wen Zhang, and Oscar Dahlsten

Many supervised learning tasks have intrinsic symmetries, such as translational and rotational symmetry in image classifications. These symmetries can be exploited to enhance performance. We formulate the symmetry constraints into a concise mathematical form. We design two ways to adopt the constrai…

[Phys. Rev. A 110, 022406] Published Mon Aug 05, 2024

Author(s): Jihao Ma, Jungeng Zhou, Jiahao Huang, and Chaohong Lee

One-axis twisting (OAT) and two-axis twisting (TAT) are well-known methods for achieving entanglement-enhanced quantum metrology, and their time-reversal echo offers a potent tool for approaching the Heisenberg limit even with detection noise. However, flipping the sign of interaction to implement t…

[Phys. Rev. A 110, 022407] Published Mon Aug 05, 2024

Author(s): Botao Du, Ramya Suresh, Santiago López, Jeremy Cadiente, and Ruichao Ma

Transport measurements are fundamental for understanding condensed matter phenomena, from superconductivity to the fractional quantum Hall effect. Analogously, they can be powerful tools for probing synthetic quantum matter in quantum simulators. Here we demonstrate the measurement of in situ partic…

[Phys. Rev. Lett. 133, 060601] Published Mon Aug 05, 2024

Author(s): Annabelle Bohrdt

A new manipulation technique could enable the realization of more versatile quantum simulators.

[Physics 17, 120] Published Mon Aug 05, 2024

Author(s): Keitaro Anai, Shion Ikehara, Yoshichika Yano, Daichi Okuno, and Shuntaro Takeda

Among various quantum machine learning (QML) algorithms, the quantum kernel method has especially attracted attention due to its compatibility with noisy intermediate-scale quantum devices and its potential to achieve quantum advantage. This method performs classification and regression by nonlinear…

[Phys. Rev. A 110, 022404] Published Fri Aug 02, 2024

Author(s): Victor F. dos Santos and Jonas Maziero

Recently, the entanglement dynamics of two harmonic oscillators initially prepared in a separable-coherent state was demonstrated to offer a pathway for prime number identification. This article presents a generalized approach and outlines a deterministic algorithm making possible the implementation…

[Phys. Rev. A 110, 022405] Published Fri Aug 02, 2024

Author(s): Nicolò Defenu, David Mukamel, and Stefano Ruffo

Ensemble inequivalence, i.e., the possibility of observing different thermodynamic properties depending on the statistical ensemble which describes the system, is one of the hallmarks of long-range physics, which has been demonstrated in numerous classical systems. Here, an example of ensemble inequ…

[Phys. Rev. Lett. 133, 050403] Published Fri Aug 02, 2024

Author(s): Eric Vernier, Hsiu-Chung Yeh, Lorenzo Piroli, and Aditi Mitra

Robust edge modes exist for a class of integrable spin chains in the interacting Floquet setting.

[Phys. Rev. Lett. 133, 050606] Published Fri Aug 02, 2024

Author(s): Mark Buchanan

New data on the rotation around both long and short axes of plastic strands may help researchers track and remove microplastics that pollute the ocean.

[Physics 17, 122] Published Fri Aug 02, 2024

Author(s): Li-Na Zheng, Xiu-Yun Zhang, Ai-Lei He, and Lu Qi

We show that both the efficiency and robustness of the topological excitation transmission can be optimized by the phase factor of the long-range hopping in the dimerized lattice. This phenomenon can be explained as the fact that the phase factor in the hopping can widen the minimal energy space aro…

[Phys. Rev. A 110, 022401] Published Thu Aug 01, 2024

Author(s): Yijia Xu (许逸葭), Yixu Wang (王亦许), and Victor V. Albert

We develop quantum information processing primitives for the planar rotor, the state space of a particle on a circle. The n-rotor Clifford group, U(1)n(n+1)/2⋊GLn(Z), is represented by continuous U(1) gates generated by polynomials quadratic in angular momenta, as well as discrete GLn(Z) gates gener…

[Phys. Rev. A 110, 022402] Published Thu Aug 01, 2024