Physical Review X最新文献

{"title":"Effects of Polydispersity and Concentration on Elastocapillary Thinning of Dilute Polymer Solutions","authors":"Vincenzo Calabrese, Amy Q. Shen, Simon J. Haward","doi":"10.1103/physrevx.15.021025","DOIUrl":"https://doi.org/10.1103/physrevx.15.021025","url":null,"abstract":"The self-thinning of liquid bridges under the action of capillarity occurs in widespread processes like jetting, dripping, and spraying and gives rise to a strong extensional flow capable of stretching dissolved polymers. If the resulting elastic stress exceeds the viscous stress, an exponential “elastocapillary” (EC) thinning regime arises, yielding a timescale τ</a:mi>EC</a:mi></a:mrow></a:msub></a:math> that is commonly considered equivalent to the longest relaxation time of the polymer <c:math xmlns:c=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><c:mi>λ</c:mi></c:math>. A long-standing question is why <e:math xmlns:e=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><e:msub><e:mi>τ</e:mi><e:mrow><e:mi>EC</e:mi></e:mrow></e:msub></e:math> depends strongly on the polymer concentration, even at high dilutions where <g:math xmlns:g=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><g:mi>λ</g:mi></g:math> should be constant in theory. To date, this is understood in terms of intermolecular interactions that arise due to “self-concentration” effects as polymers stretch. However, <i:math xmlns:i=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><i:mi>λ</i:mi></i:math> depends on the polymer molecular weight <k:math xmlns:k=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><k:mi>M</k:mi></k:math>, and we show how the concentration dependence of <m:math xmlns:m=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><m:msub><m:mi>τ</m:mi><m:mrow><m:mi>EC</m:mi></m:mrow></m:msub></m:math> can be explained by considering the molecular weight distribution (MWD) inherent in real polymer samples, without the need to invoke self-concentration. We demonstrate this by blending low-<o:math xmlns:o=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><o:mi>M</o:mi></o:math> and high-<q:math xmlns:q=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><q:mi>M</q:mi></q:math> polymer samples with narrow MWDs at dilute concentrations and in different proportions and by measuring <s:math xmlns:s=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><s:msub><s:mi>τ</s:mi><s:mrow><s:mi>EC</s:mi></s:mrow></s:msub></s:math> for each blend in capillary thinning experiments. Through a simple model that qualitatively reproduces the experimental results, we show how elastic stresses generated by the polymer build up prior to the EC regime due to the sequential stretching of progressively decreasing molecular weight species in the MWD. Since the elastic stress generated by each species depends on its concentration, the fraction of the MWD that is required to stretch in order to induce the EC regime depends on the total polymer concentration <u:math xmlns:u=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><u:mi>c</u:mi></u:math> in the solution. For higher <w:math xmlns:w=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><w:mi>c</w:mi></w:math>, the EC regime is induced by stretching of a higher-<y:math xmlns:y=\"http://www.w3.org/1998/Math/Ma","PeriodicalId":20161,"journal":{"name":"Physical Review X","volume":"13 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143866284","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":"Photocurrent Nanoscopy of Quantum Hall Bulk","authors":"Ran Jing, Boyi Zhou, Jiacheng Sun, Shoujing Chen, Wenjun Zheng, Zijian Zhou, Heng Wang, Lukas Wehmeier, Bing Cheng, Michael Dapolito, Yinan Dong, Zengyi Du, G. L. Carr, Xu Du, D. N. Basov, Qiang Li, Mengkun Liu","doi":"10.1103/physrevx.15.021026","DOIUrl":"https://doi.org/10.1103/physrevx.15.021026","url":null,"abstract":"Understanding nanoscale electronic and thermal transport of two-dimensional (2D) electron systems in the quantum Hall regime, particularly in the bulk insulating state, poses considerable challenges. One of the primary difficulties arises from the presence of chiral edge channels, whose transport behavior obscures the investigation of the insulating bulk. Using near-field optical and photocurrent nanoscopy, we probe real-space variations of the optical and thermal dynamics of graphene in the quantum Hall regime without relying on complex sample or electrode geometries. Near the charge-neutrality point, we detect strong optical and photothermal signals from resonant inter-Landau-level (LL) magnetoexciton excitations between the zeroth and ±</a:mo>1</a:mn></a:mrow></a:math> st LLs, which gradually weaken with increasing doping due to Pauli blocking. Interestingly, at higher doping levels and full-integer LL fillings, photothermal signals reappear across the entire sample over an approximately <c:math xmlns:c=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><c:mrow><c:mn>10</c:mn><c:mtext>−</c:mtext><c:mrow><c:mi mathvariant=\"normal\">μ</c:mi><c:mi mathvariant=\"normal\">m</c:mi></c:mrow></c:mrow></c:math> scale, indicating unexpectedly long cooling lengths and nonlocal photothermal heating through the insulating bulk. This observation suggests that thermal conductivity persists for the localized states even as electronic transport is suppressed—a clear violation of the Wiedemann-Franz law. Our experiments provide novel insights into nanoscale thermal and electronic transport in incompressible 2D gases, highlighting the roles of magnetoexcitons and chiral edge states in the thermo-optoelectric dynamics of the Dirac quantum Hall state. <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":"31 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143866336","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":"Probing Many-Body Bell Correlation Depth with Superconducting Qubits","authors":"Ke Wang, Weikang Li, Shibo Xu, Mengyao Hu, Jiachen Chen, Yaozu Wu, Chuanyu Zhang, Feitong Jin, Xuhao Zhu, Yu Gao, Ziqi Tan, Zhengyi Cui, Aosai Zhang, Ning Wang, Yiren Zou, Tingting Li, Fanhao Shen, Jiarun Zhong, Zehang Bao, Zitian Zhu, Zixuan Song, Jinfeng Deng, Hang Dong, Xu Zhang, Pengfei Zhang, Wenjie Jiang, Zhide Lu, Zheng-Zhi Sun, Hekang Li, Qiujiang Guo, Zhen Wang, Patrick Emonts, Jordi Tura, Chao Song, H. Wang, Dong-Ling Deng","doi":"10.1103/physrevx.15.021024","DOIUrl":"https://doi.org/10.1103/physrevx.15.021024","url":null,"abstract":"Quantum nonlocality describes a stronger form of quantum correlation than that of entanglement. It refutes Einstein’s belief of local realism and is among the most distinctive and enigmatic features of quantum mechanics. It is a crucial resource for achieving quantum advantages in a variety of practical applications, ranging from cryptography and certified random number generation via self-testing to machine learning. Nevertheless, the detection of nonlocality, especially in quantum many-body systems, is notoriously challenging. Here, we report an experimental certification of genuine multipartite Bell-operator correlations, which signal nonlocality in quantum many-body systems, up to 24 qubits with a fully programmable superconducting quantum processor. In particular, we employ energy as a Bell-operator correlation witness and variationally decrease the energy of a many-body system across a hierarchy of thresholds, below which an increasing Bell-operator correlation depth can be certified from experimental data. We variationally prepare the low-energy state of a two-dimensional honeycomb model with 73 qubits and certify its Bell-operator correlations by measuring an energy that surpasses the corresponding classical bound with up to 48 standard deviations. In addition, we variationally prepare a sequence of low-energy states and certify their genuine multipartite Bell-operator correlations up to 24 qubits via energies measured efficiently by parity oscillation and multiple quantum coherence techniques. Our results establish a viable approach for preparing and certifying multipartite Bell-operator correlations, which provide not only a finer benchmark beyond entanglement for quantum devices, but also a valuable guide toward exploiting multipartite Bell correlations in a wide spectrum of practical applications. <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":"108 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143862117","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":"Unitary k -Designs from Random Number-Conserving Quantum Circuits","authors":"Sumner N. Hearth, Michael O. Flynn, Anushya Chandran, Chris R. Laumann","doi":"10.1103/physrevx.15.021022","DOIUrl":"https://doi.org/10.1103/physrevx.15.021022","url":null,"abstract":"Local random circuits scramble efficiently and, accordingly, have a range of applications in quantum information and quantum dynamics. With a global U(1) charge, however, the scrambling ability is reduced; for example, such random circuits do not generate the entire group of number-conserving unitaries. We establish two results using the statistical mechanics of k&lt;/a:mi&gt;&lt;/a:math&gt;-fold replicated circuits. First, we show that finite moments cannot distinguish the ensemble that local random circuits generate from the Haar ensemble on the entire group of number-conserving unitaries. Specifically, the circuits form a &lt;c:math xmlns:c=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;c:msub&gt;&lt;c:mi&gt;k&lt;/c:mi&gt;&lt;c:mi&gt;c&lt;/c:mi&gt;&lt;/c:msub&gt;&lt;/c:math&gt;-design with &lt;e:math xmlns:e=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;e:msub&gt;&lt;e:mi&gt;k&lt;/e:mi&gt;&lt;e:mi&gt;c&lt;/e:mi&gt;&lt;/e:msub&gt;&lt;e:mo&gt;=&lt;/e:mo&gt;&lt;e:mi&gt;O&lt;/e:mi&gt;&lt;e:mo stretchy=\"false\"&gt;(&lt;/e:mo&gt;&lt;e:msup&gt;&lt;e:mi&gt;L&lt;/e:mi&gt;&lt;e:mi&gt;d&lt;/e:mi&gt;&lt;/e:msup&gt;&lt;e:mo stretchy=\"false\"&gt;)&lt;/e:mo&gt;&lt;/e:math&gt; for a system in &lt;i:math xmlns:i=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;i:mi&gt;d&lt;/i:mi&gt;&lt;/i:math&gt; spatial dimensions with linear dimension &lt;k:math xmlns:k=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;k:mi&gt;L&lt;/k:mi&gt;&lt;/k:math&gt;. Second, for &lt;m:math xmlns:m=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;m:mi&gt;k&lt;/m:mi&gt;&lt;m:mo&gt;&lt;&lt;/m:mo&gt;&lt;m:msub&gt;&lt;m:mi&gt;k&lt;/m:mi&gt;&lt;m:mi&gt;c&lt;/m:mi&gt;&lt;/m:msub&gt;&lt;/m:math&gt;, we derive bounds on the depth &lt;o:math xmlns:o=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;o:mi&gt;τ&lt;/o:mi&gt;&lt;/o:math&gt; required for the circuit to converge to an approximate &lt;q:math xmlns:q=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;q:mi&gt;k&lt;/q:mi&gt;&lt;/q:math&gt;-design. The depth is lower bounded by diffusion &lt;s:math xmlns:s=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;s:mi&gt;k&lt;/s:mi&gt;&lt;s:msup&gt;&lt;s:mi&gt;L&lt;/s:mi&gt;&lt;s:mn&gt;2&lt;/s:mn&gt;&lt;/s:msup&gt;&lt;s:mi&gt;ln&lt;/s:mi&gt;&lt;s:mo stretchy=\"false\"&gt;(&lt;/s:mo&gt;&lt;s:mi&gt;L&lt;/s:mi&gt;&lt;s:mo stretchy=\"false\"&gt;)&lt;/s:mo&gt;&lt;s:mo&gt;≲&lt;/s:mo&gt;&lt;s:mi&gt;τ&lt;/s:mi&gt;&lt;/s:math&gt;. In contrast, without number conservation &lt;w:math xmlns:w=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;w:mi&gt;τ&lt;/w:mi&gt;&lt;w:mo&gt;∼&lt;/w:mo&gt;&lt;w:mrow&gt;&lt;w:mi&gt;poly&lt;/w:mi&gt;&lt;/w:mrow&gt;&lt;w:mo stretchy=\"false\"&gt;(&lt;/w:mo&gt;&lt;w:mi&gt;k&lt;/w:mi&gt;&lt;w:mo stretchy=\"false\"&gt;)&lt;/w:mo&gt;&lt;w:mi&gt;L&lt;/w:mi&gt;&lt;/w:math&gt;. The convergence of the circuit ensemble is controlled by the low-energy properties of a frustration-free quantum statistical model which spontaneously breaks k&lt;/ab:mi&gt;&lt;/ab:math&gt; U(1) symmetries. We conjecture that the associated Goldstone modes set the spectral gap for arbitrary spatial and qudit dimensions, leading to an upper bound &lt;cb:math xmlns:cb=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"&gt;&lt;cb:mi&gt;τ&lt;/cb:mi&gt;&lt;cb:mo&gt;≲&lt;/cb:mo&gt;&lt;cb:mi&gt;k&lt;/cb:mi&gt;&lt;cb:msup&gt;&lt;cb:mi&gt;L&lt;/cb:mi&gt;&lt;cb:mrow&gt;&lt;cb:mi&gt;d&lt;/cb:mi&gt;&lt;cb:mo&gt;+&lt;/cb:mo&gt;&lt;cb:mn&gt;2&lt;/cb:mn&gt;&lt;/cb:mrow&gt;&lt;/cb:msup&gt;&lt;/cb:math&gt;. &lt;jats:supplementary-material&gt; &lt;jats:copyright-statement&gt;Published by the American Physical Society&lt;/jats:copyright-statement&gt; &lt;jats:copyright-y","PeriodicalId":20161,"journal":{"name":"Physical Review X","volume":"17 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143857741","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":"Pulling Order Back from the Brink of Disorder: Observation of a Nodal-Line Spin Liquid and Fluctuation Stabilized Order in K2IrCl6","authors":"Qiaochu Wang, Alberto de la Torre, Jose A. Rodriguez-Rivera, Andrey A. Podlesnyak, Wei Tian, Adam A. Aczel, Masaaki Matsuda, Philip J. Ryan, Jong-Woo Kim, Jeffrey G. Rau, Kemp W. Plumb","doi":"10.1103/physrevx.15.021021","DOIUrl":"https://doi.org/10.1103/physrevx.15.021021","url":null,"abstract":"Competing interactions in frustrated magnets can give rise to highly degenerate ground states from which correlated liquidlike states of matter often emerge. The scaling of this degeneracy influences the ultimate ground state, with extensive degeneracies potentially yielding quantum spin liquids, while subextensive or smaller degeneracies yield static orders. A long-standing problem is to understand how ordered states precipitate from this degenerate manifold and what echoes of the degeneracy survive ordering. Here, we use neutron scattering to experimentally demonstrate a new “nodal-line” spin liquid, where spins collectively fluctuate within a subextensive manifold spanning one-dimensional lines in reciprocal space. Realized in the spin-orbit-coupled, face-centered-cubic iridate K</a:mi>2</a:mn></a:msub>IrCl</a:mi>6</a:mn></a:msub></a:math>, we show that the subextensive degeneracy is robust, but remains susceptible to fluctuations or longer-range interactions which cooperate to select a magnetic order at low temperatures. Proximity to the nodal-line spin liquid influences the ordered state, enhancing the effects of quantum fluctuations that in turn act to stabilize the sublattice magnetization through the self-consistent opening of a large spin-wave gap. Our results demonstrate how quantum fluctuations can act counterintuitively in frustrated materials: Even in a case where fluctuations are ineffective at selecting an ordered state from a degenerate manifold, at the brink of the nodal spin liquid, they can act to protect the ordered state and dictate its low-energy 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":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143857742","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 Free Fermions Dynamics under Partial Postselected Monitoring","authors":"Chun Y. Leung, Dganit Meidan, Alessandro Romito","doi":"10.1103/physrevx.15.021020","DOIUrl":"https://doi.org/10.1103/physrevx.15.021020","url":null,"abstract":"Monitored quantum systems undergo measurement-induced phase transitions (MiPTs) stemming from the interplay between measurements and unitary dynamics. When the detector readout is postselected to match a given value, the dynamics is generated by a non-Hermitian Hamiltonian with MiPTs characterized by different universal features. Here, we derive a stochastic Schrödinger equation based on a microscopic description of continuous weak measurement. This formalism connects the monitored and postselected dynamics to a broader family of stochastic evolution. We apply the formalism to a chain of free fermions subject to partial postselected monitoring of local fermion parities. Within a two-replica approach, we obtain an effective bosonized Hamiltonian in the strong postselected limit. Using a renormalization group analysis, we find that the universality of the non-Hermitian MiPT is stable against a finite (weak) amount of stochasticity. We further show that the passage to the monitored universality occurs abruptly at finite partial postselection, which we confirm from the numerical finite size scaling of the MiPT. Our approach establishes a way to study MiPTs for arbitrary subsets of quantum trajectories and provides a potential route to tackle the experimental postselected problem. <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":"28 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143846634","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":"A Quantum Critical Line Bounds the High Field Metamagnetic Transition Surface in UTe2","authors":"Z. Wu, T. I. Weinberger, A. J. Hickey, D. V. Chichinadze, D. Shaffer, A. Cabala, H. Chen, M. Long, T. J. Brumm, W. Xie, Y. Ling, Z. Zhu, Y. Skourski, D. E. Graf, V. Sechovský, M. Vališka, G. G. Lonzarich, F. M. Grosche, A. G. Eaton","doi":"10.1103/physrevx.15.021019","DOIUrl":"https://doi.org/10.1103/physrevx.15.021019","url":null,"abstract":"Quantum critical phenomena are widely studied across various materials families, from high-temperature superconductors to magnetic insulators. They occur when a thermodynamic phase transition is suppressed to zero temperature as a function of some tuning parameter such as pressure or magnetic field. This generally yields a point of instability—a so-called quantum critical point—at which the phase transition is driven exclusively by quantum fluctuations. Here, we show that the heavy fermion metamagnet UTe</a:mi></a:mrow>2</a:mn></a:mrow></a:msub></a:mrow></a:math> possesses a quantum phase transition at extreme magnetic field strengths of over 70 T. Rather than terminating at one singular point, we find that the phase boundary is sensitive to magnetic field components in each of the three Cartesian axes of magnetic field space. This results in the transition surface being bounded by a continuous ring of quantum critical points, the locus of which forms an extended line of quantum criticality—a novel form of quantum critical phase boundary. Within this quantum critical line sits a magnetic field-induced superconducting state in a toroidal shape, which persists to fields over 70 T. We model our data by a phenomenological free energy expansion and show how a quantum critical line—rather than a more conventional singular point of instability—anchors the remarkable high magnetic field phase landscape 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>. <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":"25 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143846556","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":"Electronic Nematicity in Interface Superconducting LAO/KTO(111)","authors":"X. B. Cheng, M. Zhang, Y. Q. Sun, G. F. Chen, M. Qin, T. S. Ren, X. S. Cao, Y. W. Xie, J. Wu","doi":"10.1103/physrevx.15.021018","DOIUrl":"https://doi.org/10.1103/physrevx.15.021018","url":null,"abstract":"The symmetry of superconducting and normal states is at the core of superconductivity research. Emergent electronic nematicity, which spontaneously breaks the rotational symmetry, has been found in the normal state of various types of unconventional superconductors. Here, we exploit the angle-resolved resistivity method to systematically measure the nematicity of the interface superconducting LaAlO</a:mi></a:mrow>3</a:mn></a:msub>/</a:mo>KTaO</a:mi></a:mrow>3</a:mn></a:msub>(</a:mo>111</a:mn>)</a:mo></a:mrow></a:math> (<e:math xmlns:e=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><e:mrow><e:mi>LAO</e:mi><e:mo>/</e:mo><e:mi>KTO</e:mi></e:mrow></e:math>). Compared to the normal state, electronic nematicity is enhanced substantially by superconducting fluctuations around the superconducting temperature <g:math xmlns:g=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><g:mrow><g:msub><g:mi>T</g:mi><g:mi mathvariant=\"normal\">c</g:mi></g:msub></g:mrow></g:math>. More importantly, <j:math xmlns:j=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><j:mrow><j:msub><j:mi>T</j:mi><j:mi mathvariant=\"normal\">c</j:mi></j:msub></j:mrow></j:math> is also anisotropic in plane and angle dependent. The nematicity consists of a dominant <m:math xmlns:m=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><m:mrow><m:msub><m:mi mathvariant=\"normal\">C</m:mi><m:mn>2</m:mn></m:msub></m:mrow></m:math> component and a <p:math xmlns:p=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><p:mrow><p:msub><p:mi mathvariant=\"normal\">C</p:mi><p:mn>4</p:mn></p:msub></p:mrow></p:math> component, which can be explained by the presence of nematic domains. After the superconductivity is suppressed by a magnetic field, the uncovered quantum metal state manifests significant nematicity that is contributed by residual nematic superconducting fluctuations. A coherent picture of nematic interface superconductivity can be retrieved from the measured nematicity phase diagram that is crucial for the understanding of quantum metal state, electronic nematicity, and interface superconductivity. <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":"38 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143841040","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":"Accuracy Guarantees and Quantum Advantage in Analog Open Quantum Simulation with and without Noise","authors":"Vikram Kashyap, Georgios Styliaris, Sara Mouradian, J. Ignacio Cirac, Rahul Trivedi","doi":"10.1103/physrevx.15.021017","DOIUrl":"https://doi.org/10.1103/physrevx.15.021017","url":null,"abstract":"Many-body open quantum systems, described by Lindbladian master equations, are a rich class of physical models that display complex equilibrium and out-of-equilibrium phenomena which remain to be understood. In this paper, we theoretically analyze noisy analog quantum simulation of geometrically local open quantum systems and provide evidence that this problem both is hard to simulate on classical computers and could be approximately solved on near-term quantum devices. First, given a noiseless quantum simulator, we show that the dynamics of local observables and the fixed-point expectation values of rapidly mixing local observables in geometrically local Lindbladians can be obtained to a precision of ϵ</a:mi></a:math> in time that is <c:math xmlns:c=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><c:mrow><c:mi>poly</c:mi></c:mrow><c:mo stretchy=\"false\">(</c:mo><c:msup><c:mi>ϵ</c:mi><c:mrow><c:mo>−</c:mo><c:mn>1</c:mn></c:mrow></c:msup><c:mo stretchy=\"false\">)</c:mo></c:math> and uniform in system size. Furthermore, we establish that the quantum simulator would provide a superpolynomial advantage, in run-time scaling with respect to the target precision and either the evolution time (when simulating dynamics) or the Lindbladian’s decay rate (when simulating fixed points), over any classical algorithm for these problems, assuming <g:math xmlns:g=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><g:mrow><g:mi>BQP</g:mi><g:mo stretchy=\"false\">≠</g:mo><g:mi>BPP</g:mi></g:mrow></g:math>. We then consider the presence of noise in the quantum simulator in the form of additional geometrically local Lindbladian terms. We show that the simulation tasks considered in this paper are stable to errors; i.e., they can be solved to a noise-limited, but system-size independent, precision. Finally, we establish that, assuming <j:math xmlns:j=\"http://www.w3.org/1998/Math/MathML\" display=\"inline\"><j:mrow><j:mi>BQP</j:mi><j:mo stretchy=\"false\">≠</j:mo><j:mi>BPP</j:mi></j:mrow></j:math>, there are stable geometrically local Lindbladian simulation problems such that, as the noise rate on the simulator is reduced, classical algorithms must take time superpolynomially longer in the inverse noise rate to attain the same precision as the analog quantum simulator. <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":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143841091","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":"Deep-Learning Generation of High-Resolution Images of Live Cells in Culture Using Tri-Frequency Acoustic Images","authors":"Natsumi Fujiwara, Midori Uno, Hiroki Fukuda, Akira Nagakubo, Shao Ying Tan, Masahiro Kino-oka, Hirotsugu Ogi","doi":"10.1103/physrevx.15.021015","DOIUrl":"https://doi.org/10.1103/physrevx.15.021015","url":null,"abstract":"Ultrasound microscopy is the only technique that has the ability to monitor live-cell morphology over a long period of time without causing any damage to the cells, but its longer wavelength prevents one from obtaining high-resolution cell images. Here, we propose a deep-learning (DL) method for generating high-resolution acoustic images. By preparing datasets consisting of many pairs of acoustic and optical-microscope images for the same cells and training them, a high-resolution image comparable to optical microscopy is generated from an acoustic image. Importantly, the most accurate images are generated when three-layer (RGB) images containing not only high-frequency (approximately 180 MHz) images but also lower-frequency (approximately 100 MHz) images are used as the input images, which is attributed to enhanced acoustic absorption in the nucleus because the nucleus resonates in this low-frequency band. The DL scheme with the tri-frequency image input is applied to human mesenchymal stem cells and human induced pluripotent stem cells, and the high image-generation capability is demonstrated. As a result, high-resolution acoustic microscopy images are obtained for the same cells for over 24 h, without the typical cell damage encountered using optical imaging. <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":"50 1","pages":""},"PeriodicalIF":12.5,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143836871","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}