Pub Date : 2025-01-15DOI: 10.1103/physrevb.111.045419
Juliette Monsel, Matteo Acciai, Rafael Sánchez, Janine Splettstoesser
We propose an electronic bipartite system consisting of a working substance, in which a refrigeration process is implemented, and of a nonthermal resource region, containing a combination of different thermal baths. In the working substance, heat is extracted from the coldest of two electronic reservoirs (refrigeration) via heat transport and particle transport through a quantum dot. This quantum dot of the working substance is capacitively coupled to the resource region. In such a setup, a finite cooling power can be obtained in the working substance, while the energy exchange with the resource region exactly cancels out, on average. At the same time, is always exchanged, even on average, due to the capacitive coupling between the two parts of the bipartite system. The proposed system therefore implements an autonomous demon with fully vanishing heat extraction from the resource. Unlike macroscopic machines, nanoscale machines exhibit large fluctuations in performance, so precision becomes an important performance quantifier. We give a comprehensive description of the thermodynamic performance of the proposed autonomous demon in terms of stochastic trajectories and of full counting statistics and demonstrate that the precision of the cooling power strongly depends on the operation principle of the device. More specifically, the interplay of information flow and counterbalancing heat flows dramatically impacts the trade-off between cooling power, efficiency, and precision. We expect this insight to be of relevance for guiding the design of energy-conversion processes exploiting nonthermal resources. Published by the American Physical Society2025
{"title":"Autonomous demon exploiting heat and information at the trajectory level","authors":"Juliette Monsel, Matteo Acciai, Rafael Sánchez, Janine Splettstoesser","doi":"10.1103/physrevb.111.045419","DOIUrl":"https://doi.org/10.1103/physrevb.111.045419","url":null,"abstract":"We propose an electronic bipartite system consisting of a working substance, in which a refrigeration process is implemented, and of a nonthermal resource region, containing a combination of different thermal baths. In the working substance, heat is extracted from the coldest of two electronic reservoirs (refrigeration) via heat transport and particle transport through a quantum dot. This quantum dot of the working substance is capacitively coupled to the resource region. In such a setup, a finite cooling power can be obtained in the working substance, while the energy exchange with the resource region exactly cancels out, on average. At the same time, is always exchanged, even on average, due to the capacitive coupling between the two parts of the bipartite system. The proposed system therefore implements an autonomous demon with fully vanishing heat extraction from the resource. Unlike macroscopic machines, nanoscale machines exhibit large fluctuations in performance, so precision becomes an important performance quantifier. We give a comprehensive description of the thermodynamic performance of the proposed autonomous demon in terms of stochastic trajectories and of full counting statistics and demonstrate that the precision of the cooling power strongly depends on the operation principle of the device. More specifically, the interplay of information flow and counterbalancing heat flows dramatically impacts the trade-off between cooling power, efficiency, and precision. We expect this insight to be of relevance for guiding the design of energy-conversion processes exploiting nonthermal resources. <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":20082,"journal":{"name":"Physical Review B","volume":"24 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142986652","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}
Pub Date : 2025-01-15DOI: 10.1103/physrevb.111.014309
Philippe Suchsland, Roderich Moessner, Pieter W. Claeys
We investigate many-body dynamics where the evolution is governed by unitary circuits through the lens of “Krylov complexity,” a recently proposed measure of complexity and quantum chaos. We extend the formalism of Krylov complexity to unitary circuit dynamics and focus on Floquet circuits arising as the Trotter decomposition of Hamiltonian dynamics. For short Trotter steps the results from Hamiltonian dynamics are recovered, whereas a large Trotter step results in different universal behavior characterized by the existence of local : operators with vanishing autocorrelation functions, as exemplified in dual-unitary circuits. These operators exhibit maximal complexity growth, act as a memoryless bath for the dynamics, and can be directly probed in current quantum computing setups. These two regimes are separated by a crossover in chaotic systems. Conversely, we find that free integrable systems exhibit a nonanalytic transition between these different regimes, where maximally ergodic operators appear at a critical Trotter step. Published by the American Physical Society2025
{"title":"Krylov complexity and Trotter transitions in unitary circuit dynamics","authors":"Philippe Suchsland, Roderich Moessner, Pieter W. Claeys","doi":"10.1103/physrevb.111.014309","DOIUrl":"https://doi.org/10.1103/physrevb.111.014309","url":null,"abstract":"We investigate many-body dynamics where the evolution is governed by unitary circuits through the lens of “Krylov complexity,” a recently proposed measure of complexity and quantum chaos. We extend the formalism of Krylov complexity to unitary circuit dynamics and focus on Floquet circuits arising as the Trotter decomposition of Hamiltonian dynamics. For short Trotter steps the results from Hamiltonian dynamics are recovered, whereas a large Trotter step results in different universal behavior characterized by the existence of local : operators with vanishing autocorrelation functions, as exemplified in dual-unitary circuits. These operators exhibit maximal complexity growth, act as a memoryless bath for the dynamics, and can be directly probed in current quantum computing setups. These two regimes are separated by a crossover in chaotic systems. Conversely, we find that free integrable systems exhibit a nonanalytic transition between these different regimes, where maximally ergodic operators appear at a critical Trotter step. <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":20082,"journal":{"name":"Physical Review B","volume":"3 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142986653","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}
Pub Date : 2025-01-14DOI: 10.1103/physrevb.111.035422
Tetsuro Habe
The optical conductivity and the relevant electronic excitation processes are investigated in topologically nontrivial MXenes Mo2HfC2O2 and W2HfC2O2 utilizing first-principles calculation and effective model analysis. The numerical calculation based on the first-principles band structure reveals the presence of several characteristic features in the spectrum of optical conductivity as a function of photon energy. The drastic dependence on the photon polarization angle is also presented in terms of apparent features. In this paper, an effective model is also generated referring to the crystal symmetries and applied to reveal the microscopic origin of the characteristics. Then, it is shown that some features are strongly related to parity inversion between the conduction and valence bands, the key signature in electronic structures of topologically nontrivial insulators. Published by the American Physical Society2025
{"title":"Optical conductivity of the topologically nontrivial MXenes Mo2HfC2O2 and W2HfC2O2 : First-principles calculation and effective model analysis","authors":"Tetsuro Habe","doi":"10.1103/physrevb.111.035422","DOIUrl":"https://doi.org/10.1103/physrevb.111.035422","url":null,"abstract":"The optical conductivity and the relevant electronic excitation processes are investigated in topologically nontrivial MXenes Mo</a:mi>2</a:mn></a:msub>HfC</a:mi>2</a:mn></a:msub>O</a:mi>2</a:mn></a:msub></a:mrow></a:math> and <c:math xmlns:c=\"http://www.w3.org/1998/Math/MathML\"><c:mrow><c:msub><c:mi mathvariant=\"normal\">W</c:mi><c:mn>2</c:mn></c:msub><c:msub><c:mi>HfC</c:mi><c:mn>2</c:mn></c:msub><c:msub><c:mi mathvariant=\"normal\">O</c:mi><c:mn>2</c:mn></c:msub></c:mrow></c:math> utilizing first-principles calculation and effective model analysis. The numerical calculation based on the first-principles band structure reveals the presence of several characteristic features in the spectrum of optical conductivity as a function of photon energy. The drastic dependence on the photon polarization angle is also presented in terms of apparent features. In this paper, an effective model is also generated referring to the crystal symmetries and applied to reveal the microscopic origin of the characteristics. Then, it is shown that some features are strongly related to parity inversion between the conduction and valence bands, the key signature in electronic structures of topologically nontrivial insulators. <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":20082,"journal":{"name":"Physical Review B","volume":"77 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142981226","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}
Pub Date : 2025-01-13DOI: 10.1103/physrevb.111.035128
Johan Bylin, Rebecka Lindblad, Lennart Spode, Ralph H. Scheicher, Gunnar K. Pálsson
We investigate the influence of hydrogen on the electronic structure of a binary transition metallic glass of V80Zr20. We examine the hybridization between the hydrogen and metal atoms with the aid of hard x-ray photoelectron spectroscopy. Combined with density functional theory, we are able to show and predict the formation of s−d hybridized energy states. With optical transmission and resistivity measurements, we investigate the emergent electronic properties formed out of those altered energy states, and together with the theoretical calculations of the frequency-dependent conductivity tensor, we qualitatively support the observed strong wavelength-dependency of the hydrogen-induced changes on the optical absorption and a positive parabolic change in resistivity with hydrogen concentration. Published by the American Physical Society2025
{"title":"Influence of hydrogen on the electronic structure in the transition metallic glass V80Zr20","authors":"Johan Bylin, Rebecka Lindblad, Lennart Spode, Ralph H. Scheicher, Gunnar K. Pálsson","doi":"10.1103/physrevb.111.035128","DOIUrl":"https://doi.org/10.1103/physrevb.111.035128","url":null,"abstract":"We investigate the influence of hydrogen on the electronic structure of a binary transition metallic glass of V</a:mi>80</a:mn></a:msub>Zr</a:mi>20</a:mn></a:msub></a:mrow></a:math>. We examine the hybridization between the hydrogen and metal atoms with the aid of hard x-ray photoelectron spectroscopy. Combined with density functional theory, we are able to show and predict the formation of <c:math xmlns:c=\"http://www.w3.org/1998/Math/MathML\"><c:mrow><c:mi>s</c:mi><c:mtext>−</c:mtext><c:mi>d</c:mi></c:mrow></c:math> hybridized energy states. With optical transmission and resistivity measurements, we investigate the emergent electronic properties formed out of those altered energy states, and together with the theoretical calculations of the frequency-dependent conductivity tensor, we qualitatively support the observed strong wavelength-dependency of the hydrogen-induced changes on the optical absorption and a positive parabolic change in resistivity with hydrogen concentration. <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":20082,"journal":{"name":"Physical Review B","volume":"7 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142974814","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}
Pub Date : 2025-01-13DOI: 10.1103/physrevb.111.045415
H. K. Avetissian, H. H. Matevosyan, G. F. Mkrtchian
In this paper, we present a microscopic quantum theory that elucidates the nonlinear and nonperturbative optical response of biased bilayer graphene subjected to bichromatic strong laser fields. This response is analyzed using a four-band Hamiltonian derived from calculations. For the laser-stimulated dynamics, we employ structure gauge-invariant evolutionary equations to accurately describe the evolution of the single-particle density matrix across the entire Brillouin zone. The resonant generation of electron-hole pairs by the high-frequency component of the field, combined with the induction of high-order harmonic generation and high-order wave mixing by the strong low-frequency field component, leads to significant alterations in the resulting spectra. These changes are driven by the effects of Berry curvature and the shift vector, which modify the relative contributions of interband and intraband channels, thereby fundamentally reshaping the radiation spectra at high-order frequency multiplication. The numerical results are further supported by approximate analytical calculations, demonstrating that high-order wave mixing can be modeled using the classical trajectory analysis of electron-hole pairs, with Berry curvature and the shift vector significantly influencing the saddle-point equations. Published by the American Physical Society2025
{"title":"Berry curvature and shift vector effects at high-order wave mixing in biased bilayer graphene","authors":"H. K. Avetissian, H. H. Matevosyan, G. F. Mkrtchian","doi":"10.1103/physrevb.111.045415","DOIUrl":"https://doi.org/10.1103/physrevb.111.045415","url":null,"abstract":"In this paper, we present a microscopic quantum theory that elucidates the nonlinear and nonperturbative optical response of biased bilayer graphene subjected to bichromatic strong laser fields. This response is analyzed using a four-band Hamiltonian derived from calculations. For the laser-stimulated dynamics, we employ structure gauge-invariant evolutionary equations to accurately describe the evolution of the single-particle density matrix across the entire Brillouin zone. The resonant generation of electron-hole pairs by the high-frequency component of the field, combined with the induction of high-order harmonic generation and high-order wave mixing by the strong low-frequency field component, leads to significant alterations in the resulting spectra. These changes are driven by the effects of Berry curvature and the shift vector, which modify the relative contributions of interband and intraband channels, thereby fundamentally reshaping the radiation spectra at high-order frequency multiplication. The numerical results are further supported by approximate analytical calculations, demonstrating that high-order wave mixing can be modeled using the classical trajectory analysis of electron-hole pairs, with Berry curvature and the shift vector significantly influencing the saddle-point equations. <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":20082,"journal":{"name":"Physical Review B","volume":"90 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142974815","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}
Pub Date : 2025-01-10DOI: 10.1103/physrevb.111.035124
Pavlo Bilous, Louis Thirion, Henri Menke, Maurits W. Haverkort, Adriana Pálffy, Philipp Hansmann
A neural-network approach to optimize the selection of Slater determinants in configuration interaction calculations for condensed-matter quantum many-body systems is developed. We exemplify our algorithm on the discrete version of the single-impurity Anderson model with up to 299 bath sites. Employing a neural network classifier and active learning, our algorithm enhances computational efficiency by iteratively identifying the most relevant Slater determinants for the ground state wave function. We benchmark our results against established methods and investigate the efficiency of our approach compared to another basis truncation scheme without a neural network. Our algorithm demonstrates a substantial improvement in the efficiency of determinant selection, yielding a more compact and computationally manageable basis without compromising accuracy. Given the straightforward application of our neural-network-supported selection scheme to other model Hamiltonians of quantum many-body clusters, our algorithm can significantly advance selective configuration interaction calculations in the context of correlated condensed matter. Published by the American Physical Society2025
{"title":"Neural-network-supported basis optimizer for the configuration interaction problem in quantum many-body clusters: Feasibility study and numerical proof","authors":"Pavlo Bilous, Louis Thirion, Henri Menke, Maurits W. Haverkort, Adriana Pálffy, Philipp Hansmann","doi":"10.1103/physrevb.111.035124","DOIUrl":"https://doi.org/10.1103/physrevb.111.035124","url":null,"abstract":"A neural-network approach to optimize the selection of Slater determinants in configuration interaction calculations for condensed-matter quantum many-body systems is developed. We exemplify our algorithm on the discrete version of the single-impurity Anderson model with up to 299 bath sites. Employing a neural network classifier and active learning, our algorithm enhances computational efficiency by iteratively identifying the most relevant Slater determinants for the ground state wave function. We benchmark our results against established methods and investigate the efficiency of our approach compared to another basis truncation scheme without a neural network. Our algorithm demonstrates a substantial improvement in the efficiency of determinant selection, yielding a more compact and computationally manageable basis without compromising accuracy. Given the straightforward application of our neural-network-supported selection scheme to other model Hamiltonians of quantum many-body clusters, our algorithm can significantly advance selective configuration interaction calculations in the context of correlated condensed matter. <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":20082,"journal":{"name":"Physical Review B","volume":"95 3 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142961331","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}
Pub Date : 2025-01-09DOI: 10.1103/physrevb.111.035303
Tetsuro Habe
In this paper, the anomalous Hall effect of topologically nontrivial MXenes, M2M′C2O2, and the electronic structure in the presence of the magnetic proximity effect are theoretically investigated. The theoretical analysis is performed in two different ways: an effective model and a multi-orbital tight-binding model generated from the first-principles band structure. These two theoretical methods provide a similar profile of Berry curvature for electronic states near the bulk band gap, and they show an unconventional rise of hollowed-out peak in the profile with the tilt of the proximity magnetic potential. The anomalous Hall conductivity is also calculated as a function of the charge density and the tilt angle of the proximity magnetic order. Then, an unconventional enhancement of anomalous Hall conductivity by the tilt of magnetic order is theoretically predicted as a result of the variation of Berry curvature. Published by the American Physical Society2025
{"title":"Enhancement of the anomalous Hall effect by tilt of the Zeeman field in the topologically nontrivial MXenes M2M′C2O2","authors":"Tetsuro Habe","doi":"10.1103/physrevb.111.035303","DOIUrl":"https://doi.org/10.1103/physrevb.111.035303","url":null,"abstract":"In this paper, the anomalous Hall effect of topologically nontrivial MXenes, M</a:mi>2</a:mn></a:msub>M</a:mi>′</a:mo></a:msup>C</a:mi>2</a:mn></a:msub>O</a:mi>2</a:mn></a:msub></a:mrow></a:math>, and the electronic structure in the presence of the magnetic proximity effect are theoretically investigated. The theoretical analysis is performed in two different ways: an effective model and a multi-orbital tight-binding model generated from the first-principles band structure. These two theoretical methods provide a similar profile of Berry curvature for electronic states near the bulk band gap, and they show an unconventional rise of hollowed-out peak in the profile with the tilt of the proximity magnetic potential. The anomalous Hall conductivity is also calculated as a function of the charge density and the tilt angle of the proximity magnetic order. Then, an unconventional enhancement of anomalous Hall conductivity by the tilt of magnetic order is theoretically predicted as a result of the variation of Berry curvature. <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":20082,"journal":{"name":"Physical Review B","volume":"46 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142940230","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}
Pub Date : 2025-01-07DOI: 10.1103/physrevb.111.045117
G. Sordi, G. L. Reaney, N. Kowalski, P. Sémon, A.-M. S. Tremblay
Understanding the similarities and differences between adding or removing electrons from a charge-transfer insulator may provide insights about the origin of the electron-hole asymmetry found in cuprates. Here we study with cellular dynamical mean-field theory the Emery model set in the charge-transfer insulator regime, and dope it with either electrons or holes. We consider the normal state only and focus on the doping evolution of the orbital character of the dopants and on the nature of the doping-driven transition. Regarding the orbital character of the dopants, we found an electron-hole asymmetry: doped electrons mostly enter the copper orbitals, whereas doped holes mostly enter the oxygen orbitals. Regarding the nature of the doping-driven transition, we found no qualitative electron-hole asymmetry: On either electron or hole doping, there is a two-stage transition from a charge-transfer insulator to a strongly correlated pseudogap and then to a metal. This shows that a strongly correlated pseudogap is an emergent feature of doped correlated insulators in two dimensions, in qualitative agreement with recent experiments on ambipolar Sr1−xLaxCuO2+y cuprate films. Our results indicate that merely doping with holes or electrons a charge-transfer insulator is not sufficient for explaining the electron-hole asymmetry observed in the normal state phase diagram of cuprates. Our work reinforces the view that actual hole-doped cuprates are more correlated than their electron-doped counterparts. Published by the American Physical Society2025
{"title":"Ambipolar doping of a charge-transfer insulator in the Emery model","authors":"G. Sordi, G. L. Reaney, N. Kowalski, P. Sémon, A.-M. S. Tremblay","doi":"10.1103/physrevb.111.045117","DOIUrl":"https://doi.org/10.1103/physrevb.111.045117","url":null,"abstract":"Understanding the similarities and differences between adding or removing electrons from a charge-transfer insulator may provide insights about the origin of the electron-hole asymmetry found in cuprates. Here we study with cellular dynamical mean-field theory the Emery model set in the charge-transfer insulator regime, and dope it with either electrons or holes. We consider the normal state only and focus on the doping evolution of the orbital character of the dopants and on the nature of the doping-driven transition. Regarding the orbital character of the dopants, we found an electron-hole asymmetry: doped electrons mostly enter the copper orbitals, whereas doped holes mostly enter the oxygen orbitals. Regarding the nature of the doping-driven transition, we found no qualitative electron-hole asymmetry: On either electron or hole doping, there is a two-stage transition from a charge-transfer insulator to a strongly correlated pseudogap and then to a metal. This shows that a strongly correlated pseudogap is an emergent feature of doped correlated insulators in two dimensions, in qualitative agreement with recent experiments on ambipolar Sr</a:mi>1</a:mn>−</a:mo>x</a:mi></a:mrow></a:msub>La</a:mi>x</a:mi></a:msub>CuO</a:mi>2</a:mn>+</a:mo>y</a:mi></a:mrow></a:msub></a:mrow></a:math> cuprate films. Our results indicate that merely doping with holes or electrons a charge-transfer insulator is not sufficient for explaining the electron-hole asymmetry observed in the normal state phase diagram of cuprates. Our work reinforces the view that actual hole-doped cuprates are more correlated than their electron-doped counterparts. <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":20082,"journal":{"name":"Physical Review B","volume":"13 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142936262","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}
Pub Date : 2025-01-07DOI: 10.1103/physrevb.111.014405
Yurii Demydenko, Taras Vasiliev, Khrystyna O. Levchenko, Andrii V. Chumak, Valeri Lozovski
Brillouin light scattering (BLS) spectroscopy is a powerful tool for detecting spin waves in magnetic thin films and nanostructures. Despite comprehensive access to spin-wave properties, BLS spectroscopy suffers from the limited wave number of detectable spin waves and the typically relatively low sensitivity. In this paper, we present the results of numerical simulations based on the recently developed analytical model describing plasmon-enhanced BLS. Effective susceptibility is defined for a single plasmonic nanoparticle in the shape of an ellipsoid of rotation, for the sandwiched plasmonic nanoparticles separated by a dielectric spacer, as well as for the array of plasmonic resonators on the surface of a magnetic film. It is shown that the eccentricity of the metal nanoparticles, describing their shape, plays a leading role in enhancing the BLS signal. The optimal conditions for BLS enhancement are numerically defined for gold and silver plasmon systems for photons of different energies. The presented results define the roadmap for the experimental realization of plasmon-enhanced BLS spectroscopy. Published by the American Physical Society2025
{"title":"Plasmon-enhanced Brillouin light scattering spectroscopy for magnetic systems. II. Numerical simulations","authors":"Yurii Demydenko, Taras Vasiliev, Khrystyna O. Levchenko, Andrii V. Chumak, Valeri Lozovski","doi":"10.1103/physrevb.111.014405","DOIUrl":"https://doi.org/10.1103/physrevb.111.014405","url":null,"abstract":"Brillouin light scattering (BLS) spectroscopy is a powerful tool for detecting spin waves in magnetic thin films and nanostructures. Despite comprehensive access to spin-wave properties, BLS spectroscopy suffers from the limited wave number of detectable spin waves and the typically relatively low sensitivity. In this paper, we present the results of numerical simulations based on the recently developed analytical model describing plasmon-enhanced BLS. Effective susceptibility is defined for a single plasmonic nanoparticle in the shape of an ellipsoid of rotation, for the sandwiched plasmonic nanoparticles separated by a dielectric spacer, as well as for the array of plasmonic resonators on the surface of a magnetic film. It is shown that the eccentricity of the metal nanoparticles, describing their shape, plays a leading role in enhancing the BLS signal. The optimal conditions for BLS enhancement are numerically defined for gold and silver plasmon systems for photons of different energies. The presented results define the roadmap for the experimental realization of plasmon-enhanced BLS spectroscopy. <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":20082,"journal":{"name":"Physical Review B","volume":"8 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142936052","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}
Pub Date : 2025-01-06DOI: 10.1103/physrevb.111.035109
B. Davies, S. Barandun, E. O. Hiltunen, R. V. Craster, H. Ammari
We illuminate the fundamental mechanism responsible for the transition between the non-Hermitian skin effect and defect-induced localization in the bulk. We study a Hamiltonian with nonreciprocal couplings that exhibits the skin effect (the localization of all eigenvectors at one edge) and add an on-site defect in the center. Using a two-scale asymptotic method, we characterize the long-scale growth and decay of the eigenvectors and derive a simple and intuitive effective model for the transition that occurs when the defect is sufficiently large that one of the modes is localized at the defect site, rather than at the edge of the system. Published by the American Physical Society2025
{"title":"Two-scale effective model for defect-induced localization transitions in non-Hermitian systems","authors":"B. Davies, S. Barandun, E. O. Hiltunen, R. V. Craster, H. Ammari","doi":"10.1103/physrevb.111.035109","DOIUrl":"https://doi.org/10.1103/physrevb.111.035109","url":null,"abstract":"We illuminate the fundamental mechanism responsible for the transition between the non-Hermitian skin effect and defect-induced localization in the bulk. We study a Hamiltonian with nonreciprocal couplings that exhibits the skin effect (the localization of all eigenvectors at one edge) and add an on-site defect in the center. Using a two-scale asymptotic method, we characterize the long-scale growth and decay of the eigenvectors and derive a simple and intuitive effective model for the transition that occurs when the defect is sufficiently large that one of the modes is localized at the defect site, rather than at the edge of the system. <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":20082,"journal":{"name":"Physical Review B","volume":"27 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142929123","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}