Quantum最新文献 - Book学术

Conditional disclosure of secrets with quantum resources 有条件地披露量子资源的秘密

IF 6.4 2区物理与天体物理

Quantum Pub Date : 2025-10-16 DOI: 10.22331/q-2025-10-16-1885

Vahid R. Asadi, Kohdai Kuroiwa, Debbie Leung, Alex May, Sabrina Pasterski, Chris Waddell

{"title":"Conditional disclosure of secrets with quantum resources","authors":"Vahid R. Asadi, Kohdai Kuroiwa, Debbie Leung, Alex May, Sabrina Pasterski, Chris Waddell","doi":"10.22331/q-2025-10-16-1885","DOIUrl":"https://doi.org/10.22331/q-2025-10-16-1885","url":null,"abstract":"The conditional disclosure of secrets (CDS) primitive is among the simplest cryptographic settings in which to study the relationship between communication, randomness, and security. CDS involves two parties, Alice and Bob, who do not communicate but who wish to reveal a secret $z$ to a referee if and only if a Boolean function $f$ has $f(x,y)=1$. Alice knows $x,z$, Bob knows $y$, and the referee knows $x,y$. Recently, a quantum analogue of this primitive called CDQS was defined and related to $f$-routing, a task studied in the context of quantum position-verification. CDQS has the same inputs, outputs, and communication pattern as CDS but allows the use of shared entanglement and quantum messages. We initiate the systematic study of CDQS, with the aim of better understanding the relationship between privacy and quantum resources in the information theoretic setting. We begin by looking for quantum analogues of results already established in the classical CDS literature. Doing so we establish a number of basic properties of CDQS, including lower bounds on entanglement and communication stated in terms of measures of communication complexity. Because of the close relationship to the $f$-routing position-verification scheme, our results have relevance to the security of these schemes.","PeriodicalId":20807,"journal":{"name":"Quantum","volume":"1 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145295899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Classical simulation and quantum resource theory of non-Gaussian optics 非高斯光学的经典模拟与量子资源理论

IF 6.4 2区物理与天体物理

Quantum Pub Date : 2025-10-13 DOI: 10.22331/q-2025-10-13-1881

Oliver Hahn, Ryuji Takagi, Giulia Ferrini, Hayata Yamasaki

引用次数: 0

Quantum Error Correction resilient against Atom Loss 抗原子损耗量子纠错弹性

IF 6.4 2区物理与天体物理

Quantum Pub Date : 2025-10-13 DOI: 10.22331/q-2025-10-13-1884

Hugo Perrin, Sven Jandura, Guido Pupillo

引用次数: 0

Shadows and subsystems of generalized probabilistic theories: when tomographic incompleteness is not a loophole for contextuality proofs 广义概率理论的阴影和子系统：当层析不完备不是上下文证明的漏洞时

IF 6.4 2区物理与天体物理

Quantum Pub Date : 2025-10-13 DOI: 10.22331/q-2025-10-13-1880

David Schmid, John H. Selby, Vinicius P. Rossi, Roberto D. Baldijão, Ana Belén Sainz

{"title":"Shadows and subsystems of generalized probabilistic theories: when tomographic incompleteness is not a loophole for contextuality proofs","authors":"David Schmid, John H. Selby, Vinicius P. Rossi, Roberto D. Baldijão, Ana Belén Sainz","doi":"10.22331/q-2025-10-13-1880","DOIUrl":"https://doi.org/10.22331/q-2025-10-13-1880","url":null,"abstract":"It is commonly believed that failures of tomographic completeness undermine assessments of nonclassicality in noncontextuality experiments. In this work, we study how such failures can indeed lead to mistaken assessments of nonclassicality. We then show that proofs of the failure of noncontextuality are robust to a very broad class of failures of tomographic completeness, including the kinds of failures that are likely to occur in real experiments. We do so by showing that such proofs actually rely on a much weaker assumption that we term $textit{relative tomographic completeness}$: namely, that one's experimental procedures are tomographic $textit{for each other}$. Thus, the failure of noncontextuality can be established even with coarse-grained, effective, emergent, or virtual degrees of freedom. This also implies that the existence of a deeper theory of nature (beyond that being probed in one's experiment) does not in and of itself pose any challenge to proofs of nonclassicality. To prove these results, we first introduce a number of useful new concepts within the framework of generalized probabilistic theories (GPTs). Most notably, we introduce the notion of a GPT $subsystem$, generalizing a range of preexisting notions of subsystems (including those arising from tensor products, direct sums, decoherence processes, virtual encodings, and more). We also introduce the notion of a $shadow$ of a GPT fragment, which captures the information lost when one's states and effects are unknowingly not tomographic for one another.","PeriodicalId":20807,"journal":{"name":"Quantum","volume":"10 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145277424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On the average-case complexity of learning output distributions of quantum circuits 量子电路学习输出分布的平均情况复杂度

IF 6.4 2区物理与天体物理

Quantum Pub Date : 2025-10-13 DOI: 10.22331/q-2025-10-13-1883

Alexander Nietner, Marios Ioannou, Ryan Sweke, Richard Kueng, Jens Eisert, Marcel Hinsche, Jonas Haferkamp

{"title":"On the average-case complexity of learning output distributions of quantum circuits","authors":"Alexander Nietner, Marios Ioannou, Ryan Sweke, Richard Kueng, Jens Eisert, Marcel Hinsche, Jonas Haferkamp","doi":"10.22331/q-2025-10-13-1883","DOIUrl":"https://doi.org/10.22331/q-2025-10-13-1883","url":null,"abstract":"In this work, we show that learning the output distributions of brickwork random quantum circuits is average-case hard in the statistical query model. This learning model is widely used as an abstract computational model for most generic learning algorithms. In particular, for brickwork random quantum circuits on $n$ qubits of depth $d$, we show three main results: – At super logarithmic circuit depth $d=omega(log(n))$, any learning algorithm requires super polynomially many queries to achieve a constant probability of success over the randomly drawn instance. – There exists a $d=O(n)$, such that any learning algorithm requires $Omega(2^n)$ queries to achieve a $O(2^{-n})$ probability of success over the randomly drawn instance. – At infinite circuit depth $dtoinfty$, any learning algorithm requires $2^{2^{Omega(n)}}$ many queries to achieve a $2^{-2^{Omega(n)}}$ probability of success over the randomly drawn instance. As an auxiliary result of independent interest, we show that the output distribution of a brickwork random quantum circuit is constantly far from any fixed distribution in total variation distance with probability $1-O(2^{-n})$, which confirms a variant of a conjecture by Aaronson and Chen.","PeriodicalId":20807,"journal":{"name":"Quantum","volume":"7 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145277499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Deep-Circuit QAOA Deep-Circuit QAOA

IF 6.4 2区物理与天体物理

Quantum Pub Date : 2025-10-13 DOI: 10.22331/q-2025-10-13-1882

Gereon Koßmann, Lennart Binkowski, Lauritz van Luijk, Timo Ziegler, René Schwonnek

{"title":"Deep-Circuit QAOA","authors":"Gereon Koßmann, Lennart Binkowski, Lauritz van Luijk, Timo Ziegler, René Schwonnek","doi":"10.22331/q-2025-10-13-1882","DOIUrl":"https://doi.org/10.22331/q-2025-10-13-1882","url":null,"abstract":"Despite its popularity, several empirical and theoretical studies suggest that the quantum approximate optimization algorithm (QAOA) has persistent issues in providing a substantial practical advantage. Numerical results for few qubits and shallow circuits are, at best, ambiguous, and the well-studied barren plateau phenomenon draws a rather sobering picture for deeper circuits. However, as more and more sophisticated strategies are proposed to circumvent barren plateaus, it stands to reason which issues are actually fundamental and which merely constitute – admittedly difficult – engineering tasks. By shifting the scope from the usually considered parameter landscape to the quantum state space's geometry we can distinguish between problems that are fundamentally difficult to solve, independently of the parameterization, and those for which there could at least exist a favorable parameterization. Here, we find clear evidence for a 'no free lunch'-behavior of QAOA on a general optimization task with no further structure; individual cases have, however, to be analyzed more carefully. Based on our analysis, we propose and justify a performance indicator for the deep-circuit QAOA that can be accessed by solely evaluating statistical properties of the classical objective function. We further discuss the various favorable properties a generic QAOA instance has in the asymptotic regime of infinitely many gates, and elaborate on the immanent drawbacks of finite circuits. We provide several numerical examples of a deep-circuit QAOA method based on local search strategies and find that – in alignment with our performance indicator – some special function classes, like QUBOs, indeed admit a favorable optimization landscape.","PeriodicalId":20807,"journal":{"name":"Quantum","volume":"116 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145277428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Single-shot preparation of hypergraph product codes via dimension jump 通过维度跳跃的超图产品代码的单次制备

IF 6.4 2区物理与天体物理

Quantum Pub Date : 2025-10-07 DOI: 10.22331/q-2025-10-07-1879

Yifan Hong

引用次数: 0

Certifying quantum enhancements in thermal machines beyond the Thermodynamic Uncertainty Relation 证明热机中超越热力学不确定关系的量子增强

IF 6.4 2区物理与天体物理

Quantum Pub Date : 2025-10-07 DOI: 10.22331/q-2025-10-07-1878

José A. Almanza-Marrero, Gonzalo Manzano

{"title":"Certifying quantum enhancements in thermal machines beyond the Thermodynamic Uncertainty Relation","authors":"José A. Almanza-Marrero, Gonzalo Manzano","doi":"10.22331/q-2025-10-07-1878","DOIUrl":"https://doi.org/10.22331/q-2025-10-07-1878","url":null,"abstract":"Quantum coherence has been shown to impact the operational capabilities of quantum systems performing thermodynamic tasks in a significant way, and yet the possibility and conditions for genuine coherence-enhanced thermodynamic operation remain unclear. Introducing a comparison with classical machines using the same set of thermodynamic resources, we show that for steady-state quantum thermal machines – both autonomous and externally driven – that interact weakly with thermal reservoirs and work sources, the presence of coherence induced by perturbations in the machine Hamiltonian guarantees a genuine thermodynamic advantage under mild conditions. This advantage applies to both cases where the induced coherence is between levels with different energies or between degenerate levels. On the other hand, we show that engines subjected to noise-induced coherence can be outperformed by classical stochastic engines using exactly the same set of (incoherent) resources. We illustrate our results with three prototypical models of heat engines and refrigerators: the three-level amplifier, the three-qubit autonomous refrigerator, and a noise-induced-coherence machine.","PeriodicalId":20807,"journal":{"name":"Quantum","volume":"111 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145235049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quantum Lego and XP Stabilizer Codes 量子乐高和XP稳定器代码

IF 6.4 2区物理与天体物理

Quantum Pub Date : 2025-10-06 DOI: 10.22331/q-2025-10-06-1876

Ruohan Shen, Yixu Wang, ChunJun Cao

引用次数: 0

Quantum channel coding: Approximation algorithms and strong converse exponents 量子信道编码：近似算法和强逆指数

IF 6.4 2区物理与天体物理

Quantum Pub Date : 2025-10-06 DOI: 10.22331/q-2025-10-06-1877

Aadil Oufkir, Mario Berta

引用次数: 0