Physical Review X最新文献

{"title":"Modular Autonomous Virtualization System for Two-Dimensional Semiconductor Quantum Dot Arrays","authors":"Anantha S. Rao, Donovan Buterakos, Barnaby van Straaten, Valentin John, Cécile X. Yu, Stefan D. Oosterhout, Lucas Stehouwer, Giordano Scappucci, Menno Veldhorst, Francesco Borsoi, Justyna P. Zwolak","doi":"10.1103/physrevx.15.021034","DOIUrl":"https://doi.org/10.1103/physrevx.15.021034","url":null,"abstract":"Arrays of gate-defined semiconductor quantum dots are among the leading candidates for building scalable quantum processors. High-fidelity initialization, control, and readout of spin qubit registers require exquisite and targeted control over key Hamiltonian parameters that define the electrostatic environment. However, due to the tight gate pitch, capacitive crosstalk between gates hinders independent tuning of chemical potentials and interdot couplings. While virtual gates offer a practical solution, determining all the required cross-capacitance matrices accurately and efficiently in large quantum dot registers is an open challenge. Here, we establish a modular automated virtualization system (MAViS)—a general and modular framework for autonomously constructing a complete stack of multilayer virtual gates in real time. Our method employs machine learning techniques to rapidly extract features from two-dimensional charge stability diagrams. We then utilize computer vision and regression models to self-consistently determine all relative capacitive couplings necessary for virtualizing plunger and barrier gates in both low- and high-tunnel-coupling regimes. Using MAViS, we successfully demonstrate accurate virtualization of a dense two-dimensional array comprising ten quantum dots defined in a high-quality Ge</a:mi>/</a:mo>SiGe</a:mi></a:mrow></a:math> heterostructure. Our work offers an elegant and practical solution for the efficient control of large-scale semiconductor quantum dot 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":"95 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897846","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}

{"title":"Topological Rigidity and Non-Abelian Defect Junctions in Chiral Nematic Systems with Effective Biaxial Symmetry","authors":"Jin-Sheng Wu, Roberto Abril Valenzuela, Mark J. Bowick, Ivan I. Smalyukh","doi":"10.1103/physrevx.15.021036","DOIUrl":"https://doi.org/10.1103/physrevx.15.021036","url":null,"abstract":"We study topologically stable defect structures in systems where the defect line classification in three dimensions and associated algebra of interactions (the fundamental group) are governed by the non-Abelian eight-element group, the quaternions Q</a:mi>8</a:mn></a:msub></a:math>. The non-Abelian character of the defect algebra leads to a topological rigidity of bound defect pairs, and trivalent junctions which are the building blocks of multijunction trivalent networks. We realize such structures in laboratory chiral nematics and analyze their behavior analytically, along with numerical modeling. <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":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897845","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}

{"title":"Strongly Interacting, Two-Dimensional, Dipolar Spin Ensembles in (111)-Oriented Diamond","authors":"Lillian B. Hughes, Simon A. Meynell, Weijie Wu, Shreyas Parthasarathy, Lingjie Chen, Zhiran Zhang, Zilin Wang, Emily J. Davis, Kunal Mukherjee, Norman Y. Yao, Ania C. Bleszynski Jayich","doi":"10.1103/physrevx.15.021035","DOIUrl":"https://doi.org/10.1103/physrevx.15.021035","url":null,"abstract":"Systems of spins with strong dipolar interactions and controlled dimensionality enable new explorations in quantum sensing and simulation. In this work, we investigate the creation of strong dipolar interactions in a two-dimensional ensemble of nitrogen-vacancy (NV) centers generated via plasma-enhanced chemical vapor deposition on (111)-oriented diamond substrates. We find that diamond growth on the (111) plane yields high incorporation of spins, both nitrogen and NV centers, where the density of the latter is tunable via the miscut of the diamond substrate. Our process allows us to form dense, preferentially aligned, 2D NV ensembles with volume-normalized ac sensitivity down to η</a:mi></a:mrow>ac</a:mi></a:mrow></a:msub>=</a:mo>810</a:mn></a:mtext></a:mtext>pT</a:mi></a:mtext>μ</a:mi>m</a:mi></a:mrow>3</a:mn>/</a:mo>2</a:mn></a:mrow></a:msup></a:mtext>Hz</a:mi></a:mrow>−</a:mo>1</a:mn>/</a:mo>2</a:mn></a:mrow></a:msup></a:mrow></a:math>. Furthermore, we show that (111) affords maximally positive dipolar interactions among a 2D NV ensemble, which is crucial for leveraging dipolar-driven entanglement schemes and exploring new interacting spin physics. <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":"29 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143897844","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}

{"title":"Single-Crystal Diffuse Neutron Scattering Study of the Dipole-Octupole Quantum Spin-Ice Candidate Ce2Zr2O7 : No Apparent Octupolar Correlations Above T=0.05 K","authors":"E. M. Smith, R. Schäfer, J. Dudemaine, B. Placke, B. Yuan, Z. Morgan, F. Ye, R. Moessner, O. Benton, A. D. Bianchi, B. D. Gaulin","doi":"10.1103/physrevx.15.021033","DOIUrl":"https://doi.org/10.1103/physrevx.15.021033","url":null,"abstract":"The insulating magnetic pyrochlore Ce&lt;/a:mi&gt;&lt;/a:mrow&gt;2&lt;/a:mn&gt;&lt;/a:mrow&gt;&lt;/a:msub&gt;&lt;/a:mrow&gt;Zr&lt;/a:mi&gt;&lt;/a:mrow&gt;2&lt;/a:mn&gt;&lt;/a:mrow&gt;&lt;/a:msub&gt;O&lt;/a:mi&gt;&lt;/a:mrow&gt;7&lt;/a:mn&gt;&lt;/a:mrow&gt;&lt;/a:msub&gt;&lt;/a:mrow&gt;&lt;/a:math&gt; has gained attention as a quantum spin-ice candidate with dipole-octupole character that arises from the crystal-electric-field ground-state doublet for the &lt;d:math xmlns:d=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;d:mrow&gt;&lt;d:msup&gt;&lt;d:mrow&gt;&lt;d:mi&gt;Ce&lt;/d:mi&gt;&lt;/d:mrow&gt;&lt;d:mrow&gt;&lt;d:mn&gt;3&lt;/d:mn&gt;&lt;d:mo&gt;+&lt;/d:mo&gt;&lt;/d:mrow&gt;&lt;/d:msup&gt;&lt;/d:mrow&gt;&lt;/d:math&gt; Kramers ion. This dipole-octupole character permits both spin-ice phases based on magnetic dipoles and those based on more-exotic octupoles. This work reports low-temperature neutron diffraction measurements on single-crystal &lt;f:math xmlns:f=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;f:mrow&gt;&lt;f:mrow&gt;&lt;f:msub&gt;&lt;f:mrow&gt;&lt;f:mi&gt;Ce&lt;/f:mi&gt;&lt;/f:mrow&gt;&lt;f:mrow&gt;&lt;f:mn&gt;2&lt;/f:mn&gt;&lt;/f:mrow&gt;&lt;/f:msub&gt;&lt;/f:mrow&gt;&lt;f:msub&gt;&lt;f:mrow&gt;&lt;f:mi&gt;Zr&lt;/f:mi&gt;&lt;/f:mrow&gt;&lt;f:mrow&gt;&lt;f:mn&gt;2&lt;/f:mn&gt;&lt;/f:mrow&gt;&lt;/f:msub&gt;&lt;f:msub&gt;&lt;f:mrow&gt;&lt;f:mi mathvariant=\"normal\"&gt;O&lt;/f:mi&gt;&lt;/f:mrow&gt;&lt;f:mrow&gt;&lt;f:mn&gt;7&lt;/f:mn&gt;&lt;/f:mrow&gt;&lt;/f:msub&gt;&lt;/f:mrow&gt;&lt;/f:math&gt; with &lt;i:math xmlns:i=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;i:mi&gt;Q&lt;/i:mi&gt;&lt;/i:math&gt; coverage both at low &lt;k:math xmlns:k=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;k:mi&gt;Q&lt;/k:mi&gt;&lt;/k:math&gt;, where the magnetic form factor for dipoles is near maximal, and at high &lt;m:math xmlns:m=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;m:mi&gt;Q&lt;/m:mi&gt;&lt;/m:math&gt;, covering the region where the magnetic form factor for &lt;o:math xmlns:o=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;o:mrow&gt;&lt;o:msup&gt;&lt;o:mrow&gt;&lt;o:mi&gt;Ce&lt;/o:mi&gt;&lt;/o:mrow&gt;&lt;o:mrow&gt;&lt;o:mn&gt;3&lt;/o:mn&gt;&lt;o:mo&gt;+&lt;/o:mo&gt;&lt;/o:mrow&gt;&lt;/o:msup&gt;&lt;/o:mrow&gt;&lt;/o:math&gt; octupoles is near maximal. This study was motivated by recent powder neutron diffraction studies of other Ce-based dipole-octupole pyrochlores, &lt;q:math xmlns:q=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;q:mrow&gt;&lt;q:mrow&gt;&lt;q:msub&gt;&lt;q:mrow&gt;&lt;q:mi&gt;Ce&lt;/q:mi&gt;&lt;/q:mrow&gt;&lt;q:mrow&gt;&lt;q:mn&gt;2&lt;/q:mn&gt;&lt;/q:mrow&gt;&lt;/q:msub&gt;&lt;/q:mrow&gt;&lt;q:msub&gt;&lt;q:mrow&gt;&lt;q:mi&gt;Sn&lt;/q:mi&gt;&lt;/q:mrow&gt;&lt;q:mrow&gt;&lt;q:mn&gt;2&lt;/q:mn&gt;&lt;/q:mrow&gt;&lt;/q:msub&gt;&lt;q:msub&gt;&lt;q:mrow&gt;&lt;q:mi mathvariant=\"normal\"&gt;O&lt;/q:mi&gt;&lt;/q:mrow&gt;&lt;q:mrow&gt;&lt;q:mn&gt;7&lt;/q:mn&gt;&lt;/q:mrow&gt;&lt;/q:msub&gt;&lt;/q:mrow&gt;&lt;/q:math&gt; and &lt;t:math xmlns:t=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;t:mrow&gt;&lt;t:mrow&gt;&lt;t:msub&gt;&lt;t:mrow&gt;&lt;t:mi&gt;Ce&lt;/t:mi&gt;&lt;/t:mrow&gt;&lt;t:mrow&gt;&lt;t:mn&gt;2&lt;/t:mn&gt;&lt;/t:mrow&gt;&lt;/t:msub&gt;&lt;/t:mrow&gt;&lt;t:msub&gt;&lt;t:mrow&gt;&lt;t:mi&gt;Hf&lt;/t:mi&gt;&lt;/t:mrow&gt;&lt;t:mrow&gt;&lt;t:mn&gt;2&lt;/t:mn&gt;&lt;/t:mrow&gt;&lt;/t:msub&gt;&lt;t:msub&gt;&lt;t:mrow&gt;&lt;t:mi mathvariant=\"normal\"&gt;O&lt;/t:mi&gt;&lt;/t:mrow&gt;&lt;t:mrow&gt;&lt;t:mn&gt;7&lt;/t:mn&gt;&lt;/t:mrow&gt;&lt;/t:msub&gt;&lt;/t:mrow&gt;&lt;/t:math&gt;, which each showed temperature-dependent diffuse diffraction at high &lt;w:math xmlns:w=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;w:mi&gt;Q&lt;/w:mi&gt;&lt;/w:math&gt;, interpreted as arising from octupolar correlations. Our measurements use an optimized single-crystal diffuse scattering instrument that allows us to screen against strong","PeriodicalId":20161,"journal":{"name":"Physical Review X","volume":"42 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143889571","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}

{"title":"Controllable Highly Oriented Skyrmion Track Array in Bulk Fe3GaTe2","authors":"Yunhao Wang, Shiyu Zhu, Chensong Hua, Guojing Hu, Linxuan Li, Senhao Lv, Jianfeng Guo, Jiawei Hu, Runnong Zhou, Zizhao Gong, Chengmin Shen, Zhihai Cheng, Jinan Shi, Wu Zhou, Haitao Yang, Weichao Yu, Jiang Xiao, Hong-Jun Gao","doi":"10.1103/physrevx.15.021032","DOIUrl":"https://doi.org/10.1103/physrevx.15.021032","url":null,"abstract":"Magnetic skyrmions are emerging as promising candidates for next-generation information technologies, while the realization of scalable skyrmion lattices with tailored configurations is essential for advancing fundamental skyrmion physics and developing future applications. Here we achieved the controllable generation and regulation of a large-area, highly oriented skyrmion track array (STA) in ferromagnet Fe</a:mi></a:mrow>3</a:mn></a:msub>GaTe</a:mi></a:mrow>2</a:mn></a:msub></a:mrow></a:math> using a vector-magnetic-field manipulation technique. The orientation and ordering of STA, along with the types and density of skyrmions, are precisely controlled by modulating parameters during the manipulation. The critical roles of in-plane magnetic fields and Dzyaloshinskii-Moriya interaction in STA generation is further confirmed by micromagnetic simulation. Our findings develop a strategy for engineering large-area and highly oriented skyrmion configurations, offering a new pathway for the future application of next-generation spintronic and information technologies. <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":"72 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143884899","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}

{"title":"Quantum-Enhanced Sensing of Axion Dark Matter with a Transmon-Based Single Microwave Photon Counter","authors":"C. Braggio, L. Balembois, R. Di Vora, Z. Wang, J. Travesedo, L. Pallegoix, G. Carugno, A. Ortolan, G. Ruoso, U. Gambardella, D. D’Agostino, P. Bertet, E. Flurin","doi":"10.1103/physrevx.15.021031","DOIUrl":"https://doi.org/10.1103/physrevx.15.021031","url":null,"abstract":"We report an axion dark matter search with a haloscope equipped with a microwave photon counter. The haloscope is a tunable high quality factor three-dimensional microwave cavity placed in a magnetic field. The photon counter, operated cyclically, maps an incoming microwave photon onto the state of a superconducting transmon qubit. The measurement protocol continuously monitors the power emitted by the haloscope cavity as well as the dark count background and enables tuning of the cavity frequency to probe different axion masses. With this apparatus, we enhance by a factor of 20 the search speed that can be reached with quantum-limited linear amplifiers and set a new standard for probing the existence of axions with resonant detectors above 5 GHz. <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":"82 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143884900","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}

{"title":"Robust Nodal Behavior in the Thermal Conductivity of Superconducting UTe2","authors":"Ian M. Hayes, Tristin E. Metz, Corey E. Frank, Shanta R. Saha, Nicholas P. Butch, Vivek Mishra, P. J. Hirschfeld, Johnpierre Paglione","doi":"10.1103/physrevx.15.021029","DOIUrl":"https://doi.org/10.1103/physrevx.15.021029","url":null,"abstract":"The superconducting state of the heavy-fermion metal UTe</a:mi></a:mrow>2</a:mn></a:mrow></a:msub></a:mrow></a:math> has attracted considerable interest because of evidence of spin-triplet Cooper pairing and nontrivial topology. Progress on these questions requires identifying the presence or absence of nodes in the superconducting gap function and their dimension. In this article, we report a comprehensive study of the influence of disorder on the thermal transport in the superconducting state of <c:math xmlns:c=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><c:mrow><c:msub><c:mrow><c:mi>UTe</c:mi></c:mrow><c:mrow><c:mn>2</c:mn></c:mrow></c:msub></c:mrow></c:math>. Through detailed measurements of the magnetic-field dependence of the thermal conductivity in the zero-temperature limit, we obtain clear evidence of the presence of point nodes in the superconducting gap for all samples with transition temperatures ranging from 1.6 to 2.1 K obtained by different synthesis methods, including a refined self-flux method. This robustness implies the presence of symmetry-imposed nodes throughout the range studied, further confirmed via disorder-dependent calculations of the thermal transport in a model with a single pair of nodes. In addition to capturing the temperature dependence of the thermal conductivity up to <e:math xmlns:e=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><e:msub><e:mi>T</e:mi><e:mi>c</e:mi></e:msub></e:math>, this model provides some information about the locations of the nodes, suggesting a <g:math xmlns:g=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><g:msub><g:mi>B</g:mi><g:mrow><g:mn>1</g:mn><g:mi>u</g:mi></g:mrow></g:msub></g:math> or <i:math xmlns:i=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><i:msub><i:mi>B</i:mi><i:mrow><i:mn>2</i:mn><i:mi>u</i:mi></i:mrow></i:msub></i:math> symmetry for the superconducting order parameter. Additionally, comparing the new, ultrahigh conductivity samples to older samples reveals a crossover between a low-field and a high-field regime at a single value of the magnetic field in all samples. In the high-field regime, the thermal conductivity at different disorder levels differs from each other by a simple offset, suggesting that some simple principle determines the physics of the mixed state, a fact which may illuminate trends observed in other clean nodal superconductors. <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":"24 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143876068","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}

{"title":"Theory of Electron-Phonon Interactions in Extended Correlated Systems Probed by Resonant Inelastic X-Ray Scattering","authors":"Jinu Thomas, Debshikha Banerjee, Alberto Nocera, Steven Johnston","doi":"10.1103/physrevx.15.021030","DOIUrl":"https://doi.org/10.1103/physrevx.15.021030","url":null,"abstract":"An emerging application of resonant inelastic x-ray scattering (RIXS) is the study of lattice excitations and electron-phonon (e</a:mi></a:math>-ph) interactions in quantum materials. Despite the growing importance of this area of research, the community lacks a complete understanding of how the RIXS process excites the lattice and how these excitations encode information about the <c:math xmlns:c=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><c:mi>e</c:mi></c:math>-ph interactions. Here, we present a detailed study of the RIXS spectra of the Hubbard-Holstein model defined on extended one-dimensional lattices. Using the density matrix renormalization group method, we compute the RIXS response while treating the electron mobility, many-body interactions, and core-hole interactions on an equal footing. The predicted spectra exhibit notable differences from those obtained using the commonly adopted Lang-Firsov models, with important implications for analyzing past and future experiments. Our results provide a deeper understanding of how RIXS probes <e:math xmlns:e=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><e:mi>e</e:mi></e:math>-ph interactions and set the stage for a more realistic analysis of future experiments. <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":"8 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143876065","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}

{"title":"Topological Mixed Valence Model for Twisted Bilayer Graphene","authors":"Liam L. H. Lau, Piers Coleman","doi":"10.1103/physrevx.15.021028","DOIUrl":"https://doi.org/10.1103/physrevx.15.021028","url":null,"abstract":"Song and Bernevig (SB) have recently proposed a topological heavy-fermion description of the physics of magic angle twisted bilayer graphene (MATBG), involving the hybridization of flat-band electrons with a relativistic conduction sea. Here, we explore the consequences of this model, seeking a synthesis of understanding drawn from heavy-fermion physics and MATBG experiments. Our work identifies a key discrepancy between measured and calculated on-site Coulomb interactions, implicating renormalization effects that are not contained in the current model. With these considerations in mind, we consider a SB model with a single, renormalized on-site interaction between the f</a:mi></a:math> electrons, containing a phenomenological heavy-fermion binding potential on the moiré <c:math xmlns:c=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><c:mi>A</c:mi><c:mi>A</c:mi></c:math> sites. This feature allows the simplified model to capture the periodic reset of the chemical potential with filling and the observed stability of local moment behavior. We argue that a two-stage Kondo effect will develop in MATBG as a consequence of the relativistic conduction band: Kondo I occurs at high temperatures, establishing a coherent hybridization at the <e:math xmlns:e=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><e:mi mathvariant=\"normal\">Γ</e:mi></e:math> points and a non-Fermi liquid of incoherent fermions at the moiré <h:math xmlns:h=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><h:mi>K</h:mi></h:math> points; at much lower temperatures, Kondo II leads to a Fermi liquid in the flat band. Utilizing an auxiliary-rotor approach, we formulate a mean-field treatment of MATBG that captures this physics, describing the evolution of the normal state across a full range of filling factors. By contrasting the relative timescales of phonons and valence fluctuations in bulk heavy-fermion materials with that of MATBG, we are led to propose a valley-polaron origin to the Coulomb renormalization and the heavy-fermion binding potential identified from experiment. We also discuss the possibility that the two-fluid, non-Fermi liquid physics of the relativistic Kondo lattice is responsible for the strange-metal physics observed in MATBG. <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":"15 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143872863","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}

{"title":"Theory of Fractional Quantum Hall Liquids Coupled to Quantum Light and Emergent Graviton-Polaritons","authors":"Zeno Bacciconi, Hernan B. Xavier, Iacopo Carusotto, Titas Chanda, Marcello Dalmonte","doi":"10.1103/physrevx.15.021027","DOIUrl":"https://doi.org/10.1103/physrevx.15.021027","url":null,"abstract":"Recent breakthrough experiments have demonstrated how it is now possible to explore the dynamics of quantum Hall states interacting with quantum electromagnetic cavity fields. While the impact of strongly coupled nonlocal cavity modes on integer quantum Hall physics has been recently addressed, the effects on fractional quantum Hall (FQH) liquids—and, more generally, fractionalized states of matter—remain largely unexplored. In this work, we develop a theoretical framework for the understanding of FQH states coupled to quantum light. In particular, combining analytical arguments with tensor network simulations, we study the dynamics of a ν</a:mi>=</a:mo>1</a:mn>/</a:mo>3</a:mn></a:math> Laughlin state in a single-mode cavity with finite electric field gradients. We find that the topological signatures of the FQH state remain robust against the nonlocal cavity vacuum fluctuations, as indicated by the endurance of the quantized Hall resistivity. The entanglement spectra, however, carry direct fingerprints of light-matter entanglement and topology, revealing peculiar polaritonic replicas of the U(1) counting. As a further response to cavity fluctuations, we also find a squeezed FQH geometry, encoded in long-wavelength correlations. By exploring the low-energy excited spectrum inside the FQH phase, we identify a new neutral quasiparticle, the graviton polariton, arising from the hybridization between quadrupolar FQH collective excitations (known as gravitons) and light. Pushing the light-matter interaction to ultrastrong-coupling regimes, we find other two important effects, a cavity vacuum-induced Stark shift for charged quasiparticles and a potential instability toward a density modulated stripe phase, competing against the phase separation driven by the Stark shift. Finally, we discuss the experimental implications of our findings and possible extension of our results to more complex scenarios. <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":"24 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143872864","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}