Physical Review XPub Date : 2025-05-29DOI: 10.1103/physrevx.15.021072
Katharina Kaiser, Anna Rosławska, Michelangelo Romeo, Fabrice Scheurer, Tomáš Neuman, Guillaume Schull
{"title":"Electrically Driven Cascaded Photon Emission in a Single Molecule","authors":"Katharina Kaiser, Anna Rosławska, Michelangelo Romeo, Fabrice Scheurer, Tomáš Neuman, Guillaume Schull","doi":"10.1103/physrevx.15.021072","DOIUrl":"https://doi.org/10.1103/physrevx.15.021072","url":null,"abstract":"Controlling electrically stimulated quantum light sources (QLSs) is key for developing integrated and low-scale quantum devices. The underlying mechanisms leading to electrically driven quantum emission, however, are complex, as a large number of electronic states of the system can be involved and, thus, impact the emission dynamics. Here, we use a scanning tunneling microscope to electrically excite a model QLS, namely, a single ZnPc molecule, and disentangle the interplay of charge transfer and excited state formation. The luminescence spectra reveal two lines, associated to the emission of the neutral (exciton) and positively charged (trion) ZnPc, both exhibiting single-photon source behavior. In addition, we find a correlation between the charged and neutral emission, specifically, the signature of a photon cascade in which the radiative decay of the molecular trion is followed by the formation and decay of the exciton. By adjusting the charging vs discharging rate, we show that we can control these emission statistics. This generic strategy is further established by a comprehensive rate equation model comprising a variety of states that mediate excited state formation in the electrically driven single and cascaded photon emission process, revealing the complex internal dynamics of the molecular junction. <jats:supplementary-material> <jats:copyright-statement>Published by the American Physical Society</jats:copyright-statement> <jats:copyright-year>2025</jats:copyright-year> </jats:permissions> </jats:supplementary-material>","PeriodicalId":20161,"journal":{"name":"Physical Review X","volume":"35 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144176975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
Physical Review XPub Date : 2025-05-29DOI: 10.1103/physrevx.15.021073
Naushad A. Kamar, Mohammad Maghrebi
{"title":"Hybrid Quantum-Classical Stochastic Approach to Dissipative Spin-Boson Models","authors":"Naushad A. Kamar, Mohammad Maghrebi","doi":"10.1103/physrevx.15.021073","DOIUrl":"https://doi.org/10.1103/physrevx.15.021073","url":null,"abstract":"Spin-boson models involving many interacting spins and bosons are ubiquitous in quantum simulation platforms. At the same time, characterizing the dynamics of these quantum systems represents a significant challenge. Here, we consider general spin-boson models where bosons are subject to Markovian dissipation (e.g., due to cavity loss). We present an exact hybrid quantum-classical stochastic approach where the solution of a classical stochastic equation—mimicking the bosonic modes—is input into a quantum stochastic equation for the spins. Furthermore, the spins are effectively decoupled for each stochastic realization, which nevertheless comes at the expense of sampling over unphysical states. In contrast with existing stochastic approaches based on the influence functional formalism, we place no restriction (factorizability or Gaussianity) on the initial state, or the spin-boson coupling (except that it be linear in the bosonic operator). Markovian dissipation, being at the heart of our approach, renders the stochastic equations Markovian even in the strong coupling regime. Furthermore, it ensures hermiticity (though not positivity) of the density matrix for each realization, thus improving the convergence of stochastic sampling. Interestingly, we find a condition on the classical simulability of the system based solely on the single atom cooperativity even in a many-body setting. We benchmark and showcase the utility of our approach in several examples, specifically in cases where a direct numerical computation is unfeasible. <jats:supplementary-material> <jats:copyright-statement>Published by the American Physical Society</jats:copyright-statement> <jats:copyright-year>2025</jats:copyright-year> </jats:permissions> </jats:supplementary-material>","PeriodicalId":20161,"journal":{"name":"Physical Review X","volume":"49 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144177035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
Physical Review XPub Date : 2025-05-28DOI: 10.1103/physrevx.15.021070
Jiří Etrych, Gevorg Martirosyan, Alec Cao, Christopher J. Ho, Zoran Hadzibabic, Christoph Eigen
{"title":"Universal Quantum Dynamics of Bose Polarons","authors":"Jiří Etrych, Gevorg Martirosyan, Alec Cao, Christopher J. Ho, Zoran Hadzibabic, Christoph Eigen","doi":"10.1103/physrevx.15.021070","DOIUrl":"https://doi.org/10.1103/physrevx.15.021070","url":null,"abstract":"Predicting the emergent properties of impurities immersed in a quantum bath is a fundamental challenge that can defy quasiparticle treatments. Here, we measure the spectral properties and real-time dynamics of mobile impurities injected into a weakly interacting homogeneous Bose-Einstein condensate, using two broad Feshbach resonances to tune both the impurity-bath and intrabath interactions. For attractive impurity-bath interactions, the impurity spectrum features a single branch, which away from the resonance corresponds to a well-defined attractive polaron; near the resonance, we observe dramatic broadening of this branch, suggesting a breakdown of the quasiparticle picture. For repulsive impurity-bath interactions, the spectrum features two branches: the attractive branch that is dominated by excitations with energy close to that of the Feshbach dimer, but has a many-body character, and the repulsive polaron branch. Our measurements show that the behavior of impurities in weakly interacting baths is remarkably universal, controlled only by the bath density and a single dimensionless interaction parameter. <jats:supplementary-material> <jats:copyright-statement>Published by the American Physical Society</jats:copyright-statement> <jats:copyright-year>2025</jats:copyright-year> </jats:permissions> </jats:supplementary-material>","PeriodicalId":20161,"journal":{"name":"Physical Review X","volume":"49 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144165231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
Physical Review XPub Date : 2025-05-28DOI: 10.1103/physrevx.15.021071
Benjamin Bacq-Labreuil, Benjamin Lacasse, A.-M. S. Tremblay, David Sénéchal, Kristjan Haule
{"title":"Toward an Ab Initio Theory of High-Temperature Superconductors: A Study of Multilayer Cuprates","authors":"Benjamin Bacq-Labreuil, Benjamin Lacasse, A.-M. S. Tremblay, David Sénéchal, Kristjan Haule","doi":"10.1103/physrevx.15.021071","DOIUrl":"https://doi.org/10.1103/physrevx.15.021071","url":null,"abstract":"Significant progress toward a theory of high-temperature superconductivity in cuprates has been achieved via the study of effective one- and three-band Hubbard models. Nevertheless, material-specific predictions, while essential for constructing a comprehensive theory, remain challenging due to the complex relationship between real materials and the parameters of the effective models. By combining cluster dynamical mean-field theory and density functional theory in a charge-self-consistent manner, here we show that the goal of material-specific predictions for high-temperature superconductors from first principles is within reach. To demonstrate the capabilities of our approach, we take on the challenge of explaining the remarkable physics of multilayer cuprates by focusing on the two representative Ca</a:mi></a:mrow>(</a:mo>1</a:mn>+</a:mo>n</a:mi>)</a:mo></a:mrow></a:msub>Cu</a:mi></a:mrow>n</a:mi></a:mrow></a:msub></a:mrow>O</a:mi></a:mrow>2</a:mn>n</a:mi></a:mrow></a:msub>Cl</a:mi></a:mrow>2</a:mn></a:mrow></a:msub></a:mrow></a:mrow></a:mrow></a:math> and <f:math xmlns:f=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><f:mrow><f:msub><f:mrow><f:mi>HgBa</f:mi></f:mrow><f:mrow><f:mn>2</f:mn></f:mrow></f:msub></f:mrow><f:mrow><f:msub><f:mrow><f:mi>Ca</f:mi></f:mrow><f:mrow><f:mo stretchy=\"false\">(</f:mo><f:mi>n</f:mi><f:mo>−</f:mo><f:mn>1</f:mn><f:mo stretchy=\"false\">)</f:mo></f:mrow></f:msub><f:mrow><f:msub><f:mrow><f:mi>Cu</f:mi></f:mrow><f:mrow><f:mi>n</f:mi></f:mrow></f:msub></f:mrow><f:mrow><f:msub><f:mrow><f:mi mathvariant=\"normal\">O</f:mi></f:mrow><f:mrow><f:mo stretchy=\"false\">(</f:mo><f:mn>2</f:mn><f:mi>n</f:mi><f:mo>+</f:mo><f:mn>2</f:mn><f:mo stretchy=\"false\">)</f:mo></f:mrow></f:msub></f:mrow></f:mrow></f:math> families. We shed light on the microscopic origin of many salient features of multilayer cuprates, in particular, the <m:math xmlns:m=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><m:mi>n</m:mi></m:math> dependence of their superconducting properties. The growth of <o:math xmlns:o=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><o:msub><o:mi>T</o:mi><o:mi>c</o:mi></o:msub></o:math> from the single-layer to the trilayer compounds is here explained by the reduction of the charge transfer gap and, consequently, the growth of superexchange <q:math xmlns:q=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><q:mi>J</q:mi></q:math> as <s:math xmlns:s=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><s:mi>n</s:mi></s:math> increases. The origin of both is traced to the appearance of low-energy conduction bands reminiscent of standing wave modes confined within the stack of <u:math xmlns:u=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><u:mrow><u:msub><u:mrow><u:mi>CuO</u:mi></u:mrow><u:mrow><u:mn>2</u:mn></u:mrow></u:msub></u:mrow></u:math> planes. We interpret the ultimate drop of <w:math xmlns:w=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><w:msub><w:mi>T</w:mi><w:mi>c</w:mi></w:msub></w:m","PeriodicalId":20161,"journal":{"name":"Physical Review X","volume":"58 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144165230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
Physical Review XPub Date : 2025-05-27DOI: 10.1103/physrevx.15.021067
Sébastien Roux, Christophe Arnold, Etienne Carré, Alexandre Plaud, Lei Ren, Frédéric Fossard, Nicolas Horezan, Eli Janzen, James H. Edgar, Camille Maestre, Bérangère Toury, Catherine Journet, Vincent Garnier, Philippe Steyer, Takashi Taniguchi, Kenji Watanabe, Cédric Robert, Xavier Marie, François Ducastelle, Annick Loiseau, Julien Barjon
{"title":"Exciton Self-Trapping in Twisted Hexagonal Boron Nitride homostructures","authors":"Sébastien Roux, Christophe Arnold, Etienne Carré, Alexandre Plaud, Lei Ren, Frédéric Fossard, Nicolas Horezan, Eli Janzen, James H. Edgar, Camille Maestre, Bérangère Toury, Catherine Journet, Vincent Garnier, Philippe Steyer, Takashi Taniguchi, Kenji Watanabe, Cédric Robert, Xavier Marie, François Ducastelle, Annick Loiseau, Julien Barjon","doi":"10.1103/physrevx.15.021067","DOIUrl":"https://doi.org/10.1103/physrevx.15.021067","url":null,"abstract":"One of the main interests of 2D materials is their ability to be assembled with many degrees of freedom for tuning and manipulating excitonic properties. There is a need to understand how the structure of the interfaces between atomic layers influences exciton properties. Here we use cathodoluminescence and time-resolved cathodoluminescence experiments to study how excitons interact with the interface between two twisted hexagonal boron nitride (h</a:mi></a:mrow></a:math>-BN) crystals with various angles. An efficient capture of free excitons by the interface is demonstrated, which leads to a population of long-lived and interface-localized (2D) excitons. Temperature-dependent experiments indicate that for high twist angles, these excitons localized at the interface further undergo a self-trapping. It consists in a distortion of the lattice around the exciton on which the exciton traps itself. Our results suggest that this exciton-interface interaction causes the broad 4-eV optical emission of highly twisted <c:math xmlns:c=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><c:mrow><c:mi>h</c:mi></c:mrow></c:math>-BN–<e:math xmlns:e=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><e:mrow><e:mi>h</e:mi></e:mrow></e:math>-BN structures. Exciton self-trapping is finally discussed as a common feature of <g:math xmlns:g=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><g:mi>s</g:mi><g:msup><g:mi>p</g:mi><g:mn>2</g:mn></g:msup></g:math> hybridized boron nitride polytypes and nanostructures due to the ionic nature of the B—N bond and the small size of their excitons. <jats:supplementary-material> <jats:copyright-statement>Published by the American Physical Society</jats:copyright-statement> <jats:copyright-year>2025</jats:copyright-year> </jats:permissions> </jats:supplementary-material>","PeriodicalId":20161,"journal":{"name":"Physical Review X","volume":"33 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144154195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
Physical Review XPub Date : 2025-05-27DOI: 10.1103/physrevx.15.021069
T. Joas, F. Ferlemann, R. Sailer, P. J. Vetter, J. Zhang, R. S. Said, T. Teraji, S. Onoda, T. Calarco, G. Genov, M. M. Müller, F. Jelezko
{"title":"High-Fidelity Electron Spin Gates for Scaling Diamond Quantum Registers","authors":"T. Joas, F. Ferlemann, R. Sailer, P. J. Vetter, J. Zhang, R. S. Said, T. Teraji, S. Onoda, T. Calarco, G. Genov, M. M. Müller, F. Jelezko","doi":"10.1103/physrevx.15.021069","DOIUrl":"https://doi.org/10.1103/physrevx.15.021069","url":null,"abstract":"Diamond is a promising platform for quantum information processing as it can host highly coherent qubits that could allow for the construction of large quantum registers. A prerequisite for such devices is a coherent interaction between nitrogen-vacancy (NV) electron spins enabling scalable entanglement. Entanglement between dipolar-coupled NV spin pairs has been demonstrated but with a limited fidelity, and its error sources have not been characterized. Here, we design and implement a robust two-qubit gate between NV electron spins in diamond and quantify the influence of multiple error sources on the gate performance. Experimentally, we demonstrate a record gate fidelity of F</a:mi></a:mrow>2</a:mn>q</a:mi></a:mrow></a:msub>=</a:mo>(</a:mo>96.0</a:mn>±</a:mo>2.5</a:mn>)</a:mo>%</a:mi></a:mrow></a:math> under ambient conditions. Our identification of the dominant errors paves the way towards NV-NV gates beyond the error correction threshold. <jats:supplementary-material> <jats:copyright-statement>Published by the American Physical Society</jats:copyright-statement> <jats:copyright-year>2025</jats:copyright-year> </jats:permissions> </jats:supplementary-material>","PeriodicalId":20161,"journal":{"name":"Physical Review X","volume":"19 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144154303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
Physical Review XPub Date : 2025-05-27DOI: 10.1103/physrevx.15.021068
Dillon J. Cislo, Anastasios Pavlopoulos, Boris I. Shraiman
{"title":"“Morphogenetic Action” Principle for 3D Shape Formation by the Growth of Thin Sheets","authors":"Dillon J. Cislo, Anastasios Pavlopoulos, Boris I. Shraiman","doi":"10.1103/physrevx.15.021068","DOIUrl":"https://doi.org/10.1103/physrevx.15.021068","url":null,"abstract":"How does growth encode form in developing organisms? Many different spatiotemporal growth profiles may sculpt tissues into the same target 3D shapes, but only specific growth patterns are observed in animal and plant development. In particular, growth profiles may differ in their degree of spatial variation and growth anisotropy; however, the criteria that distinguish observed patterns of growth from other possible alternatives are not understood. Here we exploit the mathematical formalism of quasiconformal transformations to formulate the problem of “growth pattern selection” quantitatively in the context of 3D shape formation by growing 2D epithelial sheets. We propose that nature settles on growth patterns that are the “simplest” in a certain way. Specifically, we demonstrate that growth pattern selection can be formulated as an optimization problem and solved for the trajectories that minimize spatiotemporal variation in areal growth rates and deformation anisotropy. The result is a complete prediction for the growth of the surface, including not only a set of intermediate shapes, but also a prediction for cell displacement along those surfaces in the process of growth. Optimization of growth trajectories for both idealized surfaces and those observed in nature show that relative growth rates can be uniformized at the cost of introducing anisotropy. Minimizing the variation of programmed growth rates can therefore be viewed as a generic mechanism for growth pattern selection and may help us to understand the prevalence of anisotropy in developmental programs. <jats:supplementary-material> <jats:copyright-statement>Published by the American Physical Society</jats:copyright-statement> <jats:copyright-year>2025</jats:copyright-year> </jats:permissions> </jats:supplementary-material>","PeriodicalId":20161,"journal":{"name":"Physical Review X","volume":"3 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144154197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
Physical Review XPub Date : 2025-05-23DOI: 10.1103/physrevx.15.021066
Shan-Feng Shao, Lai Zhou, Jinping Lin, Mariella Minder, Chengfang Ge, Yuan-Mei Xie, Ao Shen, Zhengyu Yan, Hua-Lei Yin, Zhiliang Yuan
{"title":"High-Rate Measurement-Device-Independent Quantum Communication without Optical Reference Light","authors":"Shan-Feng Shao, Lai Zhou, Jinping Lin, Mariella Minder, Chengfang Ge, Yuan-Mei Xie, Ao Shen, Zhengyu Yan, Hua-Lei Yin, Zhiliang Yuan","doi":"10.1103/physrevx.15.021066","DOIUrl":"https://doi.org/10.1103/physrevx.15.021066","url":null,"abstract":"In the realm of long-distance quantum communication, asynchronous measurement-device-independent quantum key distribution (AMDI-QKD) stands out for its experimental simplicity and high key rate generation. Despite these advantages, there exists a challenge in finding a balance between simplifying the laser system further and achieving high key rates. To address this challenge, we have devised a postmeasurement compensation scheme to accurately estimate the mutual frequency offset between two compact lasers using just the announced quantum-signal detection results, thereby obviating the need for optical reference light. As a result, we demonstrate an AMDI-QKD system operating at 2.5 GHz and achieving secure key rates (SKRs) of 537 and 101</a:mn></a:mtext></a:mtext>kbit</a:mi>/</a:mo>s</a:mi></a:mrow></a:math> at distances of 100 and 201 km, respectively, showcasing a significant key rate improvement compared to similar setups. By leveraging ultrastable lasers, we achieve the highest SKRs with measurement-device-independent security within the 100–400-km range. Over 100 km, we reach a remarkable key rate of <d:math xmlns:d=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><d:mrow><d:mn>1.03</d:mn><d:mtext> </d:mtext><d:mtext> </d:mtext><d:mi>Mbit</d:mi><d:mo>/</d:mo><d:mi mathvariant=\"normal\">s</d:mi></d:mrow></d:math>, which could enable real-time one-time-pad video encryption. These findings render AMDI-QKD as a promising contender for the establishment of high performance and cost-effective large-scale intercity quantum networks. <jats:supplementary-material> <jats:copyright-statement>Published by the American Physical Society</jats:copyright-statement> <jats:copyright-year>2025</jats:copyright-year> </jats:permissions> </jats:supplementary-material>","PeriodicalId":20161,"journal":{"name":"Physical Review X","volume":"6 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144122485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
Physical Review XPub Date : 2025-05-22DOI: 10.1103/physrevx.15.021065
Qian Xu, Hengyun Zhou, Guo Zheng, Dolev Bluvstein, J. Pablo Bonilla Ataides, Mikhail D. Lukin, Liang Jiang
{"title":"Fast and Parallelizable Logical Computation with Homological Product Codes","authors":"Qian Xu, Hengyun Zhou, Guo Zheng, Dolev Bluvstein, J. Pablo Bonilla Ataides, Mikhail D. Lukin, Liang Jiang","doi":"10.1103/physrevx.15.021065","DOIUrl":"https://doi.org/10.1103/physrevx.15.021065","url":null,"abstract":"Quantum error correction is necessary to perform large-scale quantum computation but requires extremely large overheads in both space and time. High-rate quantum low-density-parity-check (qLDPC) codes promise a route to reduce qubit numbers, but performing computation while maintaining low space cost has required serialization of operations and extra time costs. In this work, we design fast and parallelizable logical gates for qLDPC codes and demonstrate their utility for key algorithmic subroutines such as the quantum adder. Our gate gadgets utilize transversal logical s between a data qLDPC code and a suitably constructed ancilla code to perform parallel Pauli product measurements (PPMs) on the data logical qubits. For hypergraph product codes, we show that the ancilla can be constructed by simply modifying the base classical codes of the data code, achieving parallel PPMs on a subgrid of the logical qubits with a lower space-time cost than existing schemes for an important class of circuits. Generalizations to 3D and 4D homological product codes further feature fast PPMs in constant depth. While prior work on qLDPC codes has focused on individual logical gates, we initiate the study of fault-tolerant compilation with our expanded set of native qLDPC code operations, constructing algorithmic primitives for preparing k</a:mi></a:math>-qubit Greenberger-Horne-Zeilinger states and distilling or teleporting <c:math xmlns:c=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><c:mi>k</c:mi></c:math> magic states with <e:math xmlns:e=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><e:mi>O</e:mi><e:mo stretchy=\"false\">(</e:mo><e:mn>1</e:mn><e:mo stretchy=\"false\">)</e:mo></e:math> space overhead in <i:math xmlns:i=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><i:mi>O</i:mi><i:mo stretchy=\"false\">(</i:mo><i:mn>1</i:mn><i:mo stretchy=\"false\">)</i:mo></i:math> and <m:math xmlns:m=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><m:mi>O</m:mi><m:mo stretchy=\"false\">(</m:mo><m:msqrt><m:mi>k</m:mi></m:msqrt><m:mi>log</m:mi><m:mi>k</m:mi><m:mo stretchy=\"false\">)</m:mo></m:math> logical cycles, respectively. We further generalize this to key algorithmic subroutines, demonstrating the efficient implementation of quantum adders using parallel operations. Our constructions are naturally compatible with reconfigurable architectures such as neutral atom arrays, paving the way to large-scale quantum computation with low space and time overheads. <jats:supplementary-material> <jats:copyright-statement>Published by the American Physical Society</jats:copyright-statement> <jats:copyright-year>2025</jats:copyright-year> </jats:permissions> </jats:supplementary-material>","PeriodicalId":20161,"journal":{"name":"Physical Review X","volume":"20 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144122402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
Physical Review XPub Date : 2025-05-22DOI: 10.1103/physrevx.15.021064
R. J. H. Ross, Giovanni D. Masucci, Chun Yen Lin, Teresa L. Iglesias, Sam Reiter, Simone Pigolotti
{"title":"Hyperdisordered Cell Packing on a Growing Surface","authors":"R. J. H. Ross, Giovanni D. Masucci, Chun Yen Lin, Teresa L. Iglesias, Sam Reiter, Simone Pigolotti","doi":"10.1103/physrevx.15.021064","DOIUrl":"https://doi.org/10.1103/physrevx.15.021064","url":null,"abstract":"While the physics of disordered packing in nongrowing systems is well understood, unexplored phenomena can emerge when packing takes place in growing domains. We study the arrangements of pigment cells (chromatophores) on squid skin as a biological example of a packed system on an expanding surface. We find that relative density fluctuations in cell numbers grow with spatial scale. We term this behavior “hyperdisordered,” in contrast with hyperuniform behavior in which relative fluctuations tend to zero at large scales. We find that hyperdisordered scaling, akin to that of a critical system, is quantitatively reproduced by a model in which hard disks are randomly inserted in a homogeneously growing surface. In addition, we find that chromatophores increase in size during animal development but maintain a stationary size distribution. The physical mechanisms described in our work may apply to a broad class of growing dense systems. <jats:supplementary-material> <jats:copyright-statement>Published by the American Physical Society</jats:copyright-statement> <jats:copyright-year>2025</jats:copyright-year> </jats:permissions> </jats:supplementary-material>","PeriodicalId":20161,"journal":{"name":"Physical Review X","volume":"57 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144122403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}