Papers
Star product for qubit states in phase space and star exponentials
Jasel Berra-Montiel, Alberto Molgado, Mar Sánchez-Córdova·Apr 6, 2026
In this paper, we formulate the phase space description of qubit systems using coadjoint orbits of $SU(2)$ and the Stratonovich-Weyl correspondence, yielding a deformation quantization on the sphere. The resulting star product reproduces the operator...
Tight Quantum Lower Bound for k-Distinctness
Aleksandrs Belovs·Apr 6, 2026
In this paper, we introduce a new quantum query lower bound framework. It is inspired by Zhandry's compressed oracle technique, but it also subsumes the polynomial method as a special case. Compared to Zhandry's technique, our approach has two key di...
In-Situ Simultaneous Magic State Injection on Arbitrary CSS qLDPC Codes
Kun Liu, Shifan Xu, Tomas Jochym-O'Connor +3 more·Apr 6, 2026
Quantum low-density parity-check (qLDPC) codes can encode many logical qubits within a single code block at low physical qubit overhead, yet magic state injection into such codes remains largely underexplored. Existing state injection proposals for q...
Quantum noise in ranging with optical pulses
Mylenne Manrique, Ilaria Gianani, Marco Barbieri +2 more·Apr 6, 2026
Optical frequency combs combine ultrashort pulse duration and phase stability, making them powerful resources for high-precision ranging even when affected by atmospheric dispersion. It has been established that by classical modal engineering and mdo...
A superconducting quantum circuit single artificial atom maser
Maria Mucci, Nicholas Hougland, Chun-Che Wang +4 more·Apr 6, 2026
We demonstrate a circuit QED analog of an atomic micromaser that utilizes an artificial, multi level atom, pumped into a population-inverted state by a microwave tone, as the gain medium. Our demonstration is enabled by the flexibility of the circuit...
Quantum Algorithms for Heterogeneous PDEs: The Neutron Diffusion Eigenvalue Problem
Andrew M. Childs, Lincoln Johnston, Brian Kiedrowski +2 more·Apr 6, 2026
We develop a hybrid classical-quantum algorithm to solve a type of linear reaction-diffusion equation, the neutron diffusion (generalized) k-eigenvalue problem that establishes nuclear criticality. The algorithm handles an equation with piecewise con...
Tennis-racket instability of twisted electrons
S. S. Baturin·Apr 6, 2026
We demonstrate that a weak nonlinear magnetic entrance edge induces a tennis-racket (Dzhanibekov) instability in the shell-resolved orbital pseudospin dynamics of twisted electrons propagating in a nominally uniform solenoidal field. Starting from a ...
Universal Ladder Structure Across Scales: From Quantum to Black Hole Physics
Rajes Ghosh, Rajendra Prasad Bhatt, Sumanta Chakraborty +1 more·Apr 6, 2026
Second-order ordinary linear differential equations appear ubiquitously across physics, describing the behavior of systems from the quantum world of atoms to the classical world of gravitating bodies. We present a unified symmetry-based framework tha...
Unlocking a fast adiabatic CZ gate and exact residual $ZZ$ cancellation between fixed-frequency transmons using a floating tunable coupler
Angela Q. Chen, Xian Wu, Sarah Strong +1 more·Apr 6, 2026
Tunable couplers in superconducting qubit architectures enable strong qubit-qubit interactions for two-qubit gates while suppressing unwanted coupling during single-qubit operations. However, achieving low error rates for fast two-qubit gates remains...
Instability-Enhanced Quantum Sensing with Tunable Multibody Interactions
Bidhi Vijaywargia, Jorge Chávez-Carlos, Francisco Pérez-Bernal +1 more·Apr 6, 2026
Dynamical instabilities can amplify small perturbations into measurable signals, offering a route to quantum-enhanced sensing. This mechanism was experimentally demonstrated in a collective-spin system with quadratic interactions, described by a twis...
Quantum state randomization constrained by non-Abelian symmetries
Yuhan Wu, Joaquin F. Rodriguez-Nieva·Apr 6, 2026
The emergence of randomness from unitary quantum dynamics is a central problem across diverse disciplines, ranging from the foundations of statistical mechanics to quantum algorithms and quantum computation. Physical systems are invariably subject to...
Information Propagation in Rydberg Arrays via Analog OTOC Calculations
Goksu Can Toga, Siva Darbha, Ermal Rrapaj +2 more·Apr 6, 2026
Out-of-time-order correlators (OTOCs) are the main tool for probing quantum chaos and scrambling, and have become crucial probes in many areas of quantum computing. However, the measurement of OTOCs is difficult to implement on analog quantum compute...
Mixed eigenstates in spin-boson systems with one-photon and two-photon interactions
David Villaseñor, Marko Robnik·Apr 6, 2026
Spin-boson systems have attracted increasing attention as accessible experimental platforms and for their potential applications in designing quantum technologies. One characteristic of these systems is the transition from regular to completely chaot...
Efficient simulation of noisy IQP circuits with amplitude-damping noise
Shravan Shravan, Mohsin Raza, Ariel Shlosberg·Apr 6, 2026
Efficient classical simulation of noisy intermediate-scale quantum (NISQ) circuits has been a topic of intense study over the past few years. The majority of results on efficient simulation assume that the circuits undergo some variant of unital nois...
Real-time Dynamics in 3D for up to 1000 Qubits with Neural Quantum States: Quenches and the Quantum Kibble--Zurek Mechanism
Vighnesh Dattatraya Naik, Zheng-Hang Sun, Markus Heyl·Apr 6, 2026
Exponential complexity of many-body wave functions limits accurate numerical simulations of real-time dynamics, especially beyond 1D, where rapid entanglement growth poses severe challenges. Neural Quantum States (NQS) have emerged as a powerful appr...
Geometry of Free Fermion Commutants
Marco Lastres, Sanjay Moudgalya·Apr 6, 2026
Understanding the structure of operators that commute with $k$ identical replicas of unitary ensembles, also known as their $k$-commutants, is an important problem in quantum many-body physics with deep implications for the late-time behavior of phys...
Connection between the contextuality breaking and incompatibility breaking qubit channels
Swati Kumari, Sumit Mukherjee, R. Prabhu·Apr 6, 2026
Contextuality and measurement incompatibility are two fundamental aspects of nonclassicality, and their manifestations in observed quantum correlations are often deeply interconnected. Recently, measurement incompatibility has been studied in connect...
Cloning Encrypted Quantum States in Arbitrary Dimensions
Filip-Ioan Ceară·Apr 6, 2026
Recently, Yamaguchi and Kempf [Phys. Rev. Lett. 136:010801, arXiv:2501.02757] proved that encrypted qubits can be cloned. In this work, we generalize the encrypted cloning protocol and prove that it also applies to higher-order quantum systems. Given...
Boltzmann-Loschmidt dispute reloaded quantum 150 years later
Leonardo Ermann, Alexei D. Chepelianskii, Dima L. Shepelyansky·Apr 6, 2026
The Boltzmann-Loschmidt dispute of 1876 questioned the possibility of a statistical irreversible description by time reversible classical equations of motion of atoms. Here we show analytically and numerically that the quantum chaos diffusion of cold...
Driving Quantum Heat Engines Beyond Classical Limits through Multilevel Coherence
Hui Wang, Yusef Maleki, William J. Munro +1 more·Apr 6, 2026
Quantum coherence provides a controllable thermodynamic resource that can raise or lower the effective temperature of a cavity mode, enabling efficiency tuning in quantum heat engines. Here, we derive analytic expressions for the effective engine tem...