Papers

Owen Root·Mar 8, 2026

I study a promise problem for an unknown unitary operator acting on an $n$-qubit system. The operator is promised to take one of two forms: either it implements a fixed permutation of computational basis states, or it implements the same permutation ...

Massimiliano Sassoli de Bianchi·Mar 8, 2026

Gleason's theorem is often cited as establishing the Born rule from the structure of Hilbert space, yet its original proof is mathematically sophisticated and rarely accessible to physicists. In this article we present a simple route to the essence o...

Vanik E. Mkrtchian, Armen E. Allahverdyan, Mikayel Khanbekyan·Mar 8, 2026

We consider the light scattering from a pair of point-like electrical dipoles. Whenever the polarizability of each dipole violates the optical theorem, the response of the pair (both in far-field and near-field) exhibits exact resonances as a functio...

Abdullah Efe Yildiz, Emre Ozan Polat·Mar 8, 2026

Spectral control of closely spaced excitonic transitions is essential for valleytronic photonics, nanoscale light sources, and wavelength-encoded sensing. In monolayer molybdenum disulfide (MoS2), the A and B excitons are separated by only tens of me...

Dinesh Kumar Panda, Colin Benjamin·Mar 8, 2026

We report the first realization of a fractional topological phase in a fully unitary, noninteracting discrete-time quantum walk implemented on finite cyclic graphs. Using a single-coin split-step cyclic quantum walk (SCSS-CQW), we uncover topological...

Abhijit Gadde·Mar 8, 2026

We give a general construction of genuinely multipartite entanglement signals from families of lower-partite symmetric local-unitary invariants satisfying a natural compatibility condition. Möbius inversion on the partition lattice plays a key role i...

Ovidiu Cristinel Stoica·Mar 8, 2026

This reply is also a friendly introduction to the impossibility of emergence of preferred structures from the Hamiltonian $\mathsf{H}$ and the unit vector $|ψ\rangle$ only. The obstructions to emergence are illustrated on the concrete construction of...

Yuwen Huang, Xiaojun Lin, Bin Luo +1 more·Mar 8, 2026

Distributed quantum computing (DQC) connects many small quantum processors into a single logical machine, offering a practical route to scalable quantum computation. However, most existing DQC paradigms are structure-agnostic. Circuit cutting propose...

Zuo Wang, Liang He·Mar 8, 2026

We demonstrate that the finite-temperature critical transverse-field Ising chain exhibits quantitative signatures of black-hole physics in its dual gravitational description within the AdS/CFT correspondence. Its finite-temperature dynamics and therm...

Niko Jokela, Aatu Rajala, Tobias Rindlisbacher·Mar 8, 2026

We study entanglement entropy (EE) in interacting quantum field theories (QFTs) at finite density. We argue that, in the limit of large subregions, the derivative of EE with respect to the size of the entangling region approaches the thermal entropy ...

Sergio Giardino·Mar 8, 2026

Starting from generalized position operators, we derive complex and quaternionic angular momentum operators along with their commutation algebra as well. These algebras differ from the standard Hermitian ones, especially in terms of commutation relat...

Katalin Friedl, Levente Gegő, László Kabódi +1 more·Mar 8, 2026

Quadratic Unconstrained Binary Optimization (QUBO) is a standard NP-hard optimization problem. Recently, it has gained renewed interest through quantum computing, as QUBOs directly reduce to the Ising model, on which quantum annealing devices are bas...

Dmitri B. Horoshko, Fedor Jelezko·Mar 8, 2026

We consider an optical interferometer with coherent light in one input and a squeezed vacuum in another. Such an interferometer is known to beat the standard quantum limit of sensitivity to the difference of phase shifts in its arms. We find the ulti...

Tommaso Faorlin, Lorenz Panzl, Phoebe Grosser +12 more·Mar 8, 2026

Spectral crowding of collective motional modes limits the fidelity of entangling interactions in trapped-ion quantum processors by inducing off-resonant coupling to spectator modes. We introduce a geometric-phase entangling interaction driven by a tr...

Konstantin Zaitsev, Vladimir Bizin, Dmitriy Kuzmin +1 more·Mar 8, 2026

Quantum key distribution is unbreakable in theory but may be hacked via imperfections in its hardware implementations. While many imperfections have been mitigated by countermeasures and advanced security proofs, several remain unsolved. One of these...

Clemens Lindner, Joonas Hämäläinen, Matti Raasakka·Mar 8, 2026

We introduce the concept of quantum minimal learning machine (QMLM), a supervised similarity-based learning algorithm. The algorithm is conceptually based on a classical machine learning model and adopted to work with quantum data. We will motivate t...

Kyoungho Cho, Ilkwon Sohn, Yongsoo Hwang +1 more·Mar 8, 2026

Gate fidelity -- an average fidelity over all possible input states -- is the workhorse metric for benchmarking quantum gates or circuits, yet fault-tolerant quantum computing ultimately depends on the worst-case behavior, typically quantifiable by s...

Vinayak Dixit·Mar 8, 2026

Network coordination - synchronising traffic signals, scheduling trains, assigning communication slots requires minimising pairwise costs across coupled systems. These problems are NP-hard yet share a common Fourier-sparse structure exploitable by qu...

Hansen S. Wu, Ribhu K. Kaul·Mar 8, 2026

We propose that scaling dimensions of d=3 conformal field theories can be studied on a system of qubits with near term quantum simulation platforms. Our proposal chooses couplings of quantum many-body problems on a polyhedral lattice at which the con...

Omar Bachain, Elhabib Jaloum, Mohamed Amazioug +3 more·Mar 8, 2026

The quantum Fisher information matrix (QFIM) is central to multiparameter quantum metrology, dictating the attainable sensitivity via the quantum Cramér-Rao bound. In this work, we investigate the ultimate precision limits for relativistic quantum th...