Papers

1,114 papers found

Qudit Designs and Where to Find Them

Namit Anand, Jeffrey Marshall, Jason Saied +2 more·Mar 3, 2026

Unitary t-designs are some of the most versatile tools in quantum information theory. Their applications range from randomized benchmarking and shadow tomography, to more fundamental ones such as emulating quantum chaos and establishing exponential s...

Quantum Physicsmath.RT

Steering paths mid-flight for fault-tolerance in measurement-based holonomic gates

Anirudh Lanka, Juan Garcia-Nila, Todd A. Brun·Mar 3, 2026

Continuous measurement-based holonomic quantum computation provides a route to universal logical computation in quantum error correcting codes. We introduce a fault-tolerant framework for implementing measurement-based holonomic gates that leverages ...

Quantum Physics

RIS-Enabled Wireless Channel Equalization: Adaptive RIS Equalizer and Deep Reinforcement Learning

Gal Ben-Itzhak, Ender Ayanoglu·Mar 3, 2026

Reconfigurable Intelligent Surfaces (RISs) offer a promising means of reshaping the wireless propagation environment, yet practical methods for configuring large passive arrays to achieve reliable signal equalization remain limited. Equalization is e...

cs.ITEmerging Techeess.SP

Barenco gate implementation using driven two- and three-qubit spin chains

Rafael Vieira, Edgard P. M. Amorim·Mar 2, 2026

We propose a protocol for implementing Barenco-type multi-qubit controlled gates using short driven spin chains. Starting from an Ising interaction with a transverse drive on the last spin, we construct an effective two-qubit Hamiltonian whose time e...

Quantum Physics

Constant-Time Surgery on 2D Hypergraph Product Codes with Near-Constant Space Overhead

Kathleen Chang, Zhiyang He, Theodore J. Yoder +2 more·Mar 2, 2026

Generalized code surgery is a versatile and low-overhead technique for performing fault-tolerant computation on quantum low-density parity-check (qLDPC) codes. In many settings, surgery exhibits practical space overheads, while its time overhead rema...

Quantum Physics

No More Hooks in the Surface Code: Distance-Preserving Syndrome Extraction for Arbitrary Layouts at Minimum Depth

Yuga Hirai, Shota Ikari, Yosuke Ueno +1 more·Mar 2, 2026

Hook errors are a major challenge in implementing logical operations with the surface code, because they can reduce the fault distance below the code distance. This motivates syndrome-extraction circuits that suppress hook-error effects for the stabi...

Quantum Physics

Sustaining high-fidelity quantum logic in neutral-atom circuits via mid-circuit operations

Rui Lin, You Li, Le-Tian Zheng +11 more·Mar 2, 2026

The realization of fault-tolerant quantum computation hinges on the ability to execute deep quantum circuits while maintaining gate fidelities consistently above error-correction thresholds. Although neutral-atom arrays have recently demonstrated hig...

Quantum PhysicsAtomic Physics

Three-Qubit State Preparation: Classification and Explicit Circuits

Yonghae Lee, Taewan Kim·Mar 1, 2026

We present a deterministic framework for preparing an arbitrary three-qubit pure state. To leverage entanglement structure in the state-preparation task, we classify three-qubit pure states into five types with respect to a $1|2$ bipartition. Given a...

Quantum Physics

Stairway Codes: Floquetifying Bivariate Bicycle Codes and Beyond

Shoham Jacoby, Alex Retzker, Fernando Pastawski·Feb 27, 2026

Floquet codes define fault-tolerant protocols through periodic measurement sequences that drive a dynamically evolving stabilizer group. They provide a natural framework for hardware supporting two-qubit parity measurements but no unitary entangling ...

Quantum Physics

Optimized Compilation for Distributed Quantum Computing

Michele Bandini, Davide Ferrari, Stefano Carretta +1 more·Feb 27, 2026

In many practical applications, quantum algorithms require several qubits, significantly more than those available with current noisy intermediate-scale quantum processors. Distributed quantum computing (DQC) is considered a scalable approach to incr...

Quantum Physics

Teleportation via spin-1/2 chain in solid-state quantum architecture

E. B. Fel'dman, S. I. Doronin, E. I. Kuznetsova +1 more·Feb 27, 2026

We propose the protocol for preparing the maximally entangled Bell state between remote qubits at the ends of the spin-1/2 chain governed by the specially engineered nearest-neighbor XX-Hamiltonian with excited central spin as the initial state. This...

Quantum Physics

Stabilizer Rényi entropy of 3-uniform hypergraph states

Daichi Kagamihara, Shunji Tsuchiya·Feb 27, 2026

Nonstabilizerness, also known as magic, plays a central role in universal quantum computation. Hypergraph states are nonstabilizer generalizations of graph states and constitute a key class of quantum states in various areas of quantum physics, such ...

Quantum Physics

Copy-cup Gates in Tensor Products of Group Algebra Codes

Ryan Tiew, Nikolas P. Breuckmann·Feb 26, 2026

We determine conditions on classical group algebra codes so that they have pre-orientation for cup products and copy-cup gates. This defines quantum codes that have constant-depth $\operatorname{CZ}$ and $\operatorname{CCZ}$ gates constructed via ten...

Quantum Physics

Long Range Frequency Tuning for QML

Michael Poppel, Jonas Stein, Sebastian Wölckert +2 more·Feb 26, 2026

Quantum machine learning models using angle encoding naturally represent truncated Fourier series, providing universal function approximation capabilities with sufficient circuit depth. For unary fixed-frequency encodings, circuit depth scales as O(o...

cs.LGAIEmerging TechQuantum Physics

Spin-Cat Qubit with Biased Noise in an Optical Tweezer Array

Toshi Kusano, Kosuke Shibata, Chih-Han Yeh +8 more·Feb 26, 2026

Bias-tailored quantum error correcting codes (QECCs) offer a higher error threshold than standard QECCs and have the potential to achieve lower logical errors with less space overhead. The spin-cat qubit, encoded in a large nuclear spin-$F$ system, i...

Quantum PhysicsAtomic Physics

Revisiting the Role of State Texture in Gate Identification and Fixed-Point Resource Theories

Alexander C. B. Greenwood, Joseph M. Lukens, Li Qian +1 more·Feb 26, 2026

A protocol for identifying controlled-NOT (CNOT) gates versus single-qubit-only gates in universal quantum circuits using randomized input states was recently shown to be intimately connected to the quantum resource of state texture. Here we revisit ...

Quantum Physics

The unbearable hardness of deciding about magic

Lorenzo Leone, Jens Eisert, Salvatore F. E. Oliviero·Feb 25, 2026

Identifying the boundary between classical and quantum computation is a central challenge in quantum information. In multi-qubit systems, entanglement and magic are the key resources underlying genuinely quantum behaviour. While entanglement is well ...

Quantum Physics

Computing with many encoded logical qubits beyond break-even

Shival Dasu, Matthew DeCross, Andrew Y. Guo +42 more·Feb 25, 2026

High-rate quantum error correcting (QEC) codes encode many logical qubits in a given number of physical qubits, making them promising candidates for quantum computation. Implementing high-rate codes at a scale that both frustrates classical computing...

Quantum Physics

Controlled jump in the Clifford hierarchy

Yichen Xu, Xiao Wang·Feb 25, 2026

We develop a simple and systematic route to higher levels of the qubit Clifford hierarchy by coherently controlling Clifford operations. Our approach is based on Pauli periodicity, defined for a Clifford unitary $U$ as the smallest integer $m\ge 1$ s...

Quantum PhysicsMathematical Physics

Noise-adaptive hybrid quantum convolutional neural networks based on depth-stratified feature extraction

Taehyun Kim, Israel F. Araujo, Daniel K. Park·Feb 25, 2026

Hierarchical quantum classifiers, such as quantum convolutional neural networks (QCNNs), represent recent progress toward designing effective and feasible architectures for quantum classification. However, their performance on near-term quantum hardw...

Quantum PhysicsEmerging Tech