Quantum Brain

Papers

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

Total Papers

28,188

This Month

0

Today

0

Research Volume

13,351 papers in 12 months (+7% vs prior quarter)

Research Focus Areas

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

Qubit Platforms

Hardware platform mentions in abstractsPhotonic leads

28,188 papers found

Exploring the Spectral Edge in SYK Models

Bowen Ouyang, Pratik Rath·Oct 9, 2025

Previous work on Jackiw-Teitelboim (JT) gravity has shown that, at low temperatures, the annealed entropy becomes negative and departs from the quenched entropy. From the perspective of the random-matrix theory (RMT) dual of JT gravity, this effect i...

hep-thQuantum Physics

Near-limit quantum control beyond analytic tractability in many-body spin systems

Jixing Zhang, Bo Peng, Yang Wang +11 more·Oct 9, 2025

As quantum control approaches hardware-imposed performance limits, weak effects omitted by reduced models become consequential. Assumptions required for analytic tractability then cease to guide control design and instead constrain further improvemen...

Quantum Physics

Efficient Closest Matrix Product State Learning in Logarithmic Depth

Chia-Ying Lin, Nai-Hui Chia, Shih-Han Hung·Oct 9, 2025

Learning the closest matrix product state (MPS) representation of a quantum state is known to enable useful tools for prediction and analysis of complex quantum systems. In this work, we study the problem of learning MPS in following setting: given m...

Quantum PhysicsComplexity

Chiral Edge Excitations of Fractional Chern Insulators

Xiao-Han Yang, Ji-Yao Chen, Xiao-Yu Dong·Oct 9, 2025

Edge excitations are the defining signature of chiral topologically ordered systems. In continuum fractional quantum Hall (FQH) states, these excitations are described by the chiral Luttinger liquid ($χ$LL) theory. Whether this effective description ...

cond-mat.str-elQuantum Physics

The debiased Keyl's algorithm: a new unbiased estimator for full state tomography

Angelos Pelecanos, Jack Spilecki, John Wright·Oct 9, 2025

In the problem of quantum state tomography, one is given $n$ copies of an unknown rank-$r$ mixed state $ρ\in \mathbb{C}^{d \times d}$ and asked to produce an estimator of $ρ$. In this work, we present the debiased Keyl's algorithm, the first estimato...

Quantum Physics

Voxel-scale quantum state control in nanorod ensembles using reconfigurable needle beams

G. A. Mantashian, D. B. Hayrapetyan, P. A. Mantashyan·Oct 9, 2025

Precisely addressing single nanostructures inside dense ensembles remains a bottleneck for scalable photonic and quantum information devices. Here we demonstrate, through comprehensive finite element and variational Monte-Carlo modelling, that a reco...

physics.opticsQuantum Physics

Beyond AME: A Novel Connection between Quantum Secret Sharing Schemes and $k$-Uniform States

Xuhong Liu, Shuai Shao·Oct 9, 2025

We study the connection between quantum secret sharing (QSS) schemes and $k$-uniform states of qubits beyond the equivalence between threshold QSS schemes and AME states. Specifically, we focus on homogeneous access structures and show that $3$-unifo...

Quantum Physicscs.IT

Block encoding with low gate count for second-quantized Hamiltonians

Diyi Liu, Shuchen Zhu, Guang Hao Low +2 more·Oct 9, 2025

Efficient block encoding of many-body Hamiltonians is a central requirement for quantum algorithms in scientific computing, particularly in the early fault-tolerant era. In this work, we introduce new explicit constructions for block encoding second-...

Quantum Physicsmath.NA

Speed limits of two-qutrit gates

Bora Basyildiz, Zhexuan Gong, Sahel Ashhab·Oct 9, 2025

The speed of elementary quantum gates sets a limit on the speed at which quantum circuits can be applied and, as a result, the size of the computations that can be performed on a quantum computer. This limitation stems from the fact that present-day ...

Quantum Physics

Quantum Shannon Information Theory -Design of communication, cipher and sensor-

Osamu Hirota·Oct 9, 2025

One of the key aspects of Shannon's theory is that it provides guidance for designing the most efficient systems, such as minimizing errors and clarifying the limits of coding. Such theories have made great developments in the 50 years since 1948. It...

Quantum Physics

Speed of evolution in qutrit systems

Jesica Espino-González, Francisco J. Sevilla, Andrea Valdés-Hernández·Oct 9, 2025

The speed of evolution between perfectly distinguishable states is thoroughly analyzed in a closed three-level (qutrit) quantum system. Considering an evolution under an arbitrary time-independent Hamiltonian, we fully characterize the relevant param...

Quantum Physics

Optimal lower bounds for quantum state tomography

Thilo Scharnhorst, Jack Spilecki, John Wright·Oct 9, 2025

We show that $n = Ω(rd/\varepsilon^2)$ copies are necessary to learn a rank $r$ mixed state $ρ\in \mathbb{C}^{d \times d}$ up to error $\varepsilon$ in trace distance. This matches the upper bound of $n = O(rd/\varepsilon^2)$ from prior work, and the...

Quantum PhysicsComplexityData Structures

Lithographic integration of TES microcalorimeters with SQUID multiplexer circuits for large format spectrometers

Robinjeet Singh, Avirup Roy, Daniel Becker +12 more·Oct 9, 2025

Arrays of hundreds or thousands of low temperature detectors have been deployed for many experiments, both bolometers for long wavelength applications and calorimeters for shorter wavelength applications. One challenge that is common to many of these...

physics.ins-detcond-mat.supr-conphysics.app-phQuantum Physics

Interpolative separable density fitting on adaptive real space grids

Hai Zhu, Chia-Nan Yeh, Miguel A. Morales +3 more·Oct 9, 2025

We generalize the interpolative separable density fitting (ISDF) method, used for compressing the four-index electron repulsion integral (ERI) tensor, to incorporate adaptive real space grids for potentially highly localized single-particle basis fun...

physics.comp-phmath.NAQuantum Physics

Photon triplets from integrated microrings: A path towards deterministic non-Gaussianity on a chip

Samuel E. Fontaine, J. E. Sipe, Marco Liscidini +1 more·Oct 9, 2025

We propose cascaded spontaneous four-wave mixing (SFWM) in microring resonators as a scalable and efficient approach for directly generating non-Gaussian states of light. Focusing on the well-understood "low-gain" regime, we demonstrate that triplet ...

Quantum Physicsphysics.optics

AI-Driven Post-Quantum Cryptography for Cyber-Resilient V2X Communication in Transportation Cyber-Physical Systems

Akid Abrar, Sagar Dasgupta, Mizanur Rahman +1 more·Oct 9, 2025

Transportation Cyber-Physical Systems (TCPS) integrate physical elements, such as transportation infrastructure and vehicles, with cyber elements via advanced communication technologies, allowing them to interact seamlessly. This integration enhances...

Computer Science

Generating Entangled Steady States in Multistable Open Quantum Systems via Initial State Control

Diego Fallas Padilla, Raphael Kaubruegger, Adrianna Gillman +2 more·Oct 8, 2025

Entanglement underpins the power of quantum technologies, yet it is fragile and typically destroyed by dissipation. Paradoxically, the same dissipation, when carefully engineered, can drive a system toward robust entangled steady states. However, thi...

Quantum Physics

Asymptotic Gate Count Bounds for Ancilla-Free Single-Qubit Synthesis with Arithmetic Gates

Kaoru Sano, Hayata Morisaki, Seiseki Akibue·Oct 8, 2025

We study ancilla-free approximation of single-qubit unitaries $U\in {\rm SU}(2)$ by gate sequences over Clifford+$G$, where $G\in\{T,V\}$ or their generalization. Let $p$ denote the characteristic factor of the gate set (e.g., $p=2$ for $G=T$ and $p=...

Quantum PhysicsMathematical Physicsmath.NT

Conjugate queries can help

Ewin Tang, John Wright, Mark Zhandry·Oct 8, 2025

We give a natural problem over input quantum oracles $U$ which cannot be solved with exponentially many black-box queries to $U$ and $U^\dagger$, but which can be solved with constant many queries to $U$ and $U^*$, or $U$ and $U^{\mathrm{T}}$. We als...

Quantum PhysicsComplexityData Structures

Reconfigurable dissipative entanglement between many spin ensembles: from robust quantum sensing to many-body state engineering

Anjun Chu, Mikhail Mamaev, Martin Koppenhöfer +2 more·Oct 8, 2025

An attractive approach for stabilizing entangled many-body spin states is to employ engineered dissipation. Most existing proposals either target relatively simple collective spin states, or require numerous independent and complex dissipative proces...

Quantum Physicscond-mat.quant-gasAtomic Physics
Quantum Intelligence

Ask about quantum research, companies, or market developments.