Quantum Physics
Symmetry is a powerful inductive bias, but in quantum reservoir computing (QRC) it cannot be imposed only by making the reservoir symmetric. QRC maps inputs through fixed quantum dynamics into nonlinear expectation-value features and trains…
We propose an Ensemble Feature Selection (EFS) method for fast estimation of process infidelity of involutory multi-qubit gates, including non-Clifford targets, for which standard Clifford-based benchmarking does not apply. The method…
In a series of papers in the 1980's Alexander Holevo proved a classification theorem for continuous quantum measurement processes, or, as they would today be called, stationary quantum trajectories in continuous time. His main tools were…
Non-invertible defects are usually diagnosed through scaling spectra or infrared CFT data. We show that the Fibonacci duality defect of the critical golden chain already carries an exact categorical fingerprint at finite lattice size. The…
Non-invertible symmetries are characterized by topological defects of irrational quantum dimension, but their imprint on the entanglement of a quantum many-body state has not been resolved at the level of the spectrum. We show that the…
Quantum metrological advantage is certified by averaged Fisher responses: contrast, susceptibility, or quantum Fisher information (QFI). This fails in quenched sensors, where slow environmental variables freeze within a session but vary…
We show that combining quantum error detection (QED) with probabilistic error cancellation (PEC) gives more accurate and lower-variance estimates than PEC alone, provided that the symmetry measurements required for QED are carefully chosen.…
Portfolio diversification - a cornerstone of modern investment management - can be formulated as a Maximum Independent Set (MIS) problem on asset correlation graphs. Solving this problem at scale is computationally challenging, motivating…
Kinetic uncertainty relations bound current precision of stochastic processes by dynamical activity. The extension of these bounds to quantum systems has been impeded by coherence, strong system-reservoir coupling, and the subtlety of…
We investigate and establish an analytic connection between the exact solutions describing the dynamics of a two-level system driven by periodic external fields, focusing on the cases of linear driving and the so-called rotating-wave…
Efficient classical simulation of large-scale quantum networks frequently relies on noise approximations, which consider a restricted set of operators to describe noisy channels and operations. In this work, we demonstrate how such…
Realizing quantum neural networks (QNNs) in industry requires knowing which quantum computing paradigm suits which task. Motivated by AI accelerators and high-bandwidth memory, where die stacking makes wafer-level defect screening central…
We give an analytical expression for the dynamical Lie algebra corresponding to the QAOA-MaxCut problem on complete graphs, and show that the variance of the associated loss function scales linearly in the number of qubits. This solves an…
We introduce the Twisted Gaussian Schell (TGS) state, a two-mode mixed Gaussian state defined as the quantum-optical analog of the Twisted Gaussian Schell-model beam of classical paraxial optics, characterized by the so-called twist phase.…
We propose a photonic platform for simulating arbitrary single-qubit open-system dynamics using a single photon in an open Mach-Zehnder interferometer. A birefringent quartz plate induces a coupling between the polarization and frequency…
Standard gate-level transpilation introduces significant physical noise and overhead for high-precision quantum algorithms, such as the Quantum Singular Value Transformation (QSVT), on near-term trapped-ion hardware. Current compilers treat…
Quantum nonlocality admits several operational manifestations, one of which emerges from sets of orthogonal quantum states that cannot be perfectly distinguished by local operations and classical communication (LOCC). Such sets are regarded…
Quantum nonlocality paradoxes, such as that of GHZ, provide maximally sharp logical obstructions to classical probabilistic models of quantum correlations. They are key resources in a broad variety of information-theoretic tasks that…
Scalable fault-tolerant quantum computation requires quantum error-correcting codes that simultaneously support universal logical operations, suppress hardware-specific noise, and enable efficient handling of photon-loss errors. Bosonic…
We study the the scattering of light by a binary system of identical atoms in which one of them is incoherently pumped. This system belongs to the kind of non-parity symmetric optical systems in which gains and losses are partially…