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Papers

Live trends in quantum computing research, updated daily from arXiv.

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27,548

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12,912 papers in 12 months (-5% vs prior quarter)

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Papers by research theme (12 months). Hover for details.

Qubit Platforms

Hardware platform mentions in abstractsPhotonic leads

4,069 papers found

Visualizing Quantum Circuits: State Vector Difference Highlighting and the Half-Matrix

Michael J. McGuffin, Jean-Marc Robert·Oct 1, 2025

Existing graphical user interfaces for circuit simulators often show small visual summaries of the reduced state of each qubit, showing the probability, phase, purity, and/or Bloch sphere coordinates associated with each qubit. These necessarily prov...

Quantum Physicscs.HC

Pre-Distillation of Magic States via Composite Schemes

Muhammad Erew, Moshe Goldstein, Yaron Oz +1 more·Oct 1, 2025

Magic state distillation (MSD) is a cornerstone of fault-tolerant quantum computing, enabling non-Clifford gates via state injection into stabilizer circuits. However, the substantial overhead of current MSD protocols remains a major obstacle to scal...

Quantum Physicscond-mat.otherMathematical Physics

Provably Optimal Quantum Circuits with Mixed-Integer Programming

Harsha Nagarajan, Zsolt Szabó·Oct 1, 2025

We present a depth-aware optimization framework for quantum circuit compilation that unifies provable optimality with scalable heuristics. For exact synthesis of a target unitary, we formulate a mixed-integer linear program (MILP) that linearly handl...

Quantum Physicscs.MSmath.OC

Linear-Size QAC0 Channels: Learning, Testing and Hardness

Yangjing Dong, Fengning Ou, Penghui Yao·Oct 1, 2025

Shallow quantum circuits have attracted increasing attention in recent years, due to the fact that current noisy quantum hardware can only perform faithful quantum computation for a short amount of time. The constant-depth quantum circuits $\mathbf{Q...

Quantum Physics

Quantum Probabilistic Label Refining: Enhancing Label Quality for Robust Image Classification

Fang Qi, Lu Peng, Zhengming Ding·Oct 1, 2025

Learning with softmax cross-entropy on one-hot labels often leads to overconfident predictions and poor robustness under noise or perturbations. Label smoothing mitigates this by redistributing some confidence uniformly, but treats all samples equall...

Quantum Physics

The non-stabilizerness cost of quantum state estimation

Gabriele Lo Monaco, Salvatore Lorenzo, Alessandro Ferraro +3 more·Sep 30, 2025

We study the non-stabilizer resources required to achieve informational completeness in single-setting quantum state estimation scenarios. We consider fixed-basis projective measurements preceded by quantum circuits acting on $n$-qubit input states, ...

Quantum Physics

Approximate Quantum State Preparation with Tree-Based Bayesian Optimization Surrogates

Nicholas S. DiBrita, Jason Han, Younghyun Cho +2 more·Sep 30, 2025

We study the problem of approximate state preparation on near-term quantum computers, where the goal is to construct a parameterized circuit that reproduces the output distribution of a target quantum state while minimizing resource overhead. This ta...

Quantum Physics

Stab-QRAM: An All-Clifford Quantum Random Access Memory for Special Data

Guangyi Li, Yu Gan, Zeguan Wu +3 more·Sep 30, 2025

Quantum random access memories (QRAMs) are pivotal for data-intensive quantum algorithms, but existing general-purpose and domain-specific architectures are hampered by a critical bottleneck: a heavy reliance on non-Clifford gates (e.g., T-gates), wh...

Quantum Physicscs.AR

Strong random unitaries and fast scrambling

Thomas Schuster, Fermi Ma, Alex Lombardi +2 more·Sep 30, 2025

Understanding how fast physical systems can resemble Haar-random unitaries is a fundamental question in physics. Many experiments of interest in quantum gravity and many-body physics, including the butterfly effect in quantum information scrambling a...

Quantum Physicscond-mat.str-elComplexityCryptography

Suppressing leakage and maintaining robustness in transmon qubits: Signatures of a trade-off relation

Pablo M. Poggi, Anthony Kiely·Sep 30, 2025

We study the problem of optimally generating quantum gates in a logical subspace embedded in a larger Hilbert space, where the dynamics is also affected by unknown static imperfections. This general problem is widespread across various emergent quant...

Quantum Physics

Enabling full localization of qubits and gates with a multi-mode coupler

Zhongyi Jiang, Simon Geisert, Sören Ihssen +2 more·Sep 30, 2025

Tunable couplers are a key building block of superconducting quantum processors, enabling high on-off ratios for two-qubit entangling interactions. While qubit-qubit interaction can be turned off, residual wavefunctions delocalize single-qubit excita...

Quantum PhysicsMesoscale Physics

Practical security of local local oscillator continuous-variable quantum key distribution systems with pulse width mismatch

Yi Zheng, Jiarui Wu, Chenlei Fang +3 more·Sep 30, 2025

In continuous-variable quantum key distribution (CVQKD) systems, using a local local oscillator (LLO) scheme removes the local oscillator side channel, enhances Bob's detection performance and reduces the excess noise caused by photon leakage, thereb...

Quantum Physics

Classical feature map surrogates and metrics for quantum control landscapes

Martino Calzavara, Tommaso Calarco, Felix Motzoi·Sep 30, 2025

We derive and analyze three feature map representations of parametrized quantum dynamics, which generalize variational quantum circuits. These are (i) a Lie-Fourier partial sum, (ii) a Taylor expansion, and (iii) a finite-dimensional sinc kernel regr...

Quantum Physics

Nonstabilizerness without Magic: Classically Simulatable Quantum States That Are Indistinguishable by Classically Simulatable Quantum Circuits

Hyukjoon Kwon·Sep 30, 2025

Quantum state discrimination plays a central role in defining the possible and impossible operations through a restricted class of quantum operations. A seminal result by Bennett et al. [Phys. Rev. A 59, 1070 (1999)] demonstrates the existence of a s...

Quantum Physics

Unitary synthesis with fewer T gates

Xinyu Tan·Sep 30, 2025

We present a simple algorithm that implements an arbitrary $n$-qubit unitary operator using a Clifford+T circuit with T-count $O(2^{4n/3} n^{2/3})$. This improves upon the previous best known upper bound of $O(2^{3n/2} n)$, while the best known lower...

Quantum PhysicsComplexity

High fidelity CNOT gates in photonic integrated circuits using composite segmented directional couplers

Jonatan Piasetzky, Amit Rotem, Yuval Warshavsky +4 more·Sep 29, 2025

Integrated photonic circuits are a promising platform for scalable quantum information processing, but their performance is often constrained by component sensitivity to fabrication imperfections. Directional couplers, which are crucial building bloc...

physics.opticsQuantum Physics

Fast quantum computation with all-to-all Hamiltonians

Chao Yin·Sep 29, 2025

All-to-all interactions arise naturally in many areas of theoretical physics and across diverse experimental quantum platforms, motivating a systematic study of their information-processing power. Assuming each pair of qubits interacts with $\mathrm{...

Quantum PhysicsMathematical Physics

Distributed Quantum Error Correction with Permutation-Invariant Approximate Codes

Connor Clayton, Bruno Avritzer·Sep 29, 2025

Modular quantum computing architectures require error correction schemes that remain effective in the presense of noisy inter-processor operations. We introduce a distributed quantum error correction framework based on approximate codes to address th...

Quantum Physics

Near-Optimal Simultaneous Estimation of Quantum State Moments

Xiao Shi, Jiyu Jiang, Xian Wu +3 more·Sep 29, 2025

Estimating nonlinear properties such as Rényi entropies and observable-weighted moments serves as a central strategy for spectrum spectroscopy, which is fundamental to property prediction and analysis in quantum information science, statistical mecha...

Quantum Physics

A Quantum Computer Based on Donor-Cluster Arrays in Silicon

Shihang Zhang, Chunhui Zhang, Guanyong Wang +4 more·Sep 29, 2025

Significant advances in silicon spin qubits highlight the potential of silicon quantum dots for scalable quantum computing, given their compatibility with industrial fabrication and long coherence times. In particular, phosphorus (P)-doped spin qubit...

Quantum PhysicsMesoscale Physics
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