arXiv: Strongly Correlated Electrons最新文献_第9页

Correlation driven phonon anomalies in bulk FeSe 大块FeSe中相关驱动声子异常

arXiv: Strongly Correlated Electrons Pub Date : 2020-10-05 DOI: 10.1103/physrevb.102.241108

G. Khanal, K. Haule

引用次数: 0

Possible multiorbital ground state in CeCu2Si2 CeCu2Si2中可能的多轨道基态

arXiv: Strongly Correlated Electrons Pub Date : 2020-10-05 DOI: 10.1103/physrevb.102.245146

A. Amorese, A. Marino, M. Sundermann, Kai Chen, Zhiwei Hu, T. Willers, F. Choueikani, P. Ohresser, J. Herrero‐Martín, S. Agrestini, C. Chen, Hong‐ji Lin, M. Haverkort, S. Seiro, C. Geibel, F. Steglich, L. Tjeng, G. Zwicknagl, A. Severing

{"title":"Possible multiorbital ground state in \u0000CeCu2Si2","authors":"A. Amorese, A. Marino, M. Sundermann, Kai Chen, Zhiwei Hu, T. Willers, F. Choueikani, P. Ohresser, J. Herrero‐Martín, S. Agrestini, C. Chen, Hong‐ji Lin, M. Haverkort, S. Seiro, C. Geibel, F. Steglich, L. Tjeng, G. Zwicknagl, A. Severing","doi":"10.1103/physrevb.102.245146","DOIUrl":"https://doi.org/10.1103/physrevb.102.245146","url":null,"abstract":"The crystal-field ground state wave function of CeCu$_2$Si$_2$ has been investigated with linear polarized $M$-edge x-ray absorption spectroscopy from 250mK to 250K, thus covering the superconducting ($T_{text{c}}$=0.6K), the Kondo ($T_{text{K}}$$approx$20K) as well as the Curie-Weiss regime. The comparison with full-multiplet calculations shows that the temperature dependence of the experimental linear dichroism is well explained with a $Gamma_7^{(1)}$ crystal-field ground-state and the thermal population of excited states at around 30meV. The crystal-field scheme does not change throughout the entire temperature range thus making the scenario of orbital switching unlikely. Spectroscopic evidence for the presence of the Ce 4$f^0$ configuration in the ground state is consistent with the possibility for a multi-orbital character of the ground state. We estimate from the Kondo temperature and crystal-field splitting energies that several percents of the higher lying $Gamma_6$ state and $Gamma_7^{(2)}$ crystal-field states are mixed into the primarily $Gamma_7^{(1)}$ ground state. This estimate is also supported by re-normalized band-structure calculations that uses the experimentally determined crystal-field scheme.","PeriodicalId":8511,"journal":{"name":"arXiv: Strongly Correlated Electrons","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88014388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Gauging the Kitaev chain 测量基塔耶夫链

arXiv: Strongly Correlated Electrons Pub Date : 2020-10-01 DOI: 10.21468/SciPostPhys.10.6.148

Umberto Borla, R. Verresen, Jeet Shah, S. Moroz

引用次数: 13

Matrix product state recursion methods for computing spectral functions of strongly correlated quantum systems 计算强相关量子系统谱函数的矩阵积态递推方法

arXiv: Strongly Correlated Electrons Pub Date : 2020-10-01 DOI: 10.1103/PHYSREVB.103.125142

Yifan Tian, S. White

引用次数: 5

Exact Self-Consistent Effective Hamiltonian Theory 精确自洽有效哈密顿理论

arXiv: Strongly Correlated Electrons Pub Date : 2020-10-01 DOI: 10.31219/osf.io/547gj

Xindong Wang

引用次数: 2

Competition of spinon Fermi surface and heavy Fermi liquid states from the periodic Anderson to the Hubbard model 从周期Anderson模型到Hubbard模型的自旋子费米表面和重费米液态的竞争

arXiv: Strongly Correlated Electrons Pub Date : 2020-10-01 DOI: 10.1103/PHYSREVB.103.085128

Chuan-yu Chen, I. Sodemann, P. Lee

{"title":"Competition of spinon Fermi surface and heavy Fermi liquid states from the periodic Anderson to the Hubbard model","authors":"Chuan-yu Chen, I. Sodemann, P. Lee","doi":"10.1103/PHYSREVB.103.085128","DOIUrl":"https://doi.org/10.1103/PHYSREVB.103.085128","url":null,"abstract":"We study a model of correlated electrons coupled by tunnelling to a layer of itinerant metallic electrons, which allows to interpolate from a frustrated limit favorable to spin liquid states to a Kondo-lattice limit favorable to interlayer coherent heavy metallic states. We study the competition of the spinon fermi surface state and the interlayer coherent heavy Kondo metal that appears with increasing tunnelling. Employing a slave rotor mean-field approach, we obtain a phase diagram and describe two regimes where the spin liquid state is destroyed by weak interlayer tunnelling, (i) the Kondo limit in which the correlated electrons can be viewed as localized spin moments and (ii) near the Mott metal-insulator-transition where the spinon fermi surface transitions continuously into a Fermi liquid. We study the shape of LDOS spectra of the putative spin liquid layer in the heavy fermi liquid phase and describe the temperature dependence of its width arising from quasiparticle interactions and disorder effects throughout this phase diagram, in an effort to understand recent STM experiments of the candidate spin liquid 1T-TaSe$_2$ residing on metallic 1H-TaSe$_2$. Comparison of the shape and temperature dependence of the theoretical and experimental LDOS suggest that this system is either close to the localized Kondo limit, or in an intermediate coupling regime where the Kondo coupling and the Heisenberg exchange interaction are comparable.","PeriodicalId":8511,"journal":{"name":"arXiv: Strongly Correlated Electrons","volume":"82 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84003174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

On non-canonical degrees of freedom 关于非规范自由度

arXiv: Strongly Correlated Electrons Pub Date : 2020-09-30 DOI: 10.21468/SCIPOSTPHYS.10.3.075

Eoin Quinn

引用次数: 2

Precise control of Jeff=12 magnetic properties in Sr2IrO4 epitaxial thin films by variation of strain and thin film thickness 通过改变应变和薄膜厚度精确控制Sr2IrO4外延薄膜的Jeff=12磁性能

arXiv: Strongly Correlated Electrons Pub Date : 2020-09-28 DOI: 10.1103/physrevb.102.214402

S. Geprägs, B. Skovdal, M. Scheufele, M. Opel, D. Wermeille, P. Thompson, A. Bombardi, V. Simonet, S. Grenier, P. Lejay, G. Chahine, D. Quintero-Castro, R. Gross, D. Mannix

{"title":"Precise control of \u0000Jeff=12\u0000 magnetic properties in \u0000Sr2IrO4\u0000 epitaxial thin films by variation of strain and thin film thickness","authors":"S. Geprägs, B. Skovdal, M. Scheufele, M. Opel, D. Wermeille, P. Thompson, A. Bombardi, V. Simonet, S. Grenier, P. Lejay, G. Chahine, D. Quintero-Castro, R. Gross, D. Mannix","doi":"10.1103/physrevb.102.214402","DOIUrl":"https://doi.org/10.1103/physrevb.102.214402","url":null,"abstract":"We report on a comprehensive investigation of the effects of strain and film thickness on the structural and magnetic properties of epitaxial thin films of the prototypal $J_mathrm{eff}=1/2$ compound Sr$_2$IrO$_4$ by advanced X-ray scattering. We find that the Sr$_2$IrO$_4$ thin films can be grown fully strained up to a thickness of 108 nm. By using X-ray resonant scattering, we show that the out-of-plane magnetic correlation length is strongly dependent on the thin film thickness, but independent of the strain state of the thin films. This can be used as a finely tuned dial to adjust the out-of-plane magnetic correlation length and transform the magnetic anisotropy from two-dimensional (2D) to three-dimensional (3D) behavior by incrementing film thickness. These results provide a clearer picture for the systematic control of the magnetic degrees of freedom in epitaxial thin films of Sr$_2$IrO$_4$ and bring to light the potential for a rich playground to explore the physics of $5d$-transition metal compounds.","PeriodicalId":8511,"journal":{"name":"arXiv: Strongly Correlated Electrons","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87220651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Magnetic field dependence of low-energy magnons, anisotropic heat conduction, and spontaneous relaxation of magnetic domains in the cubic helimagnet ZnCr2Se4 ZnCr2Se4中低能磁振子的磁场依赖性、各向异性热传导和磁畴的自发弛豫

arXiv: Strongly Correlated Electrons Pub Date : 2020-09-28 DOI: 10.1103/physrevb.102.184431

D. Inosov, Y. Onykiienko, Y. Tymoshenko, A. Akopyan, D. Shukla, N. Prasai, M. Doerr, D. Gorbunov, S. Zherlitsyn, D. Voneshen, M. Boehm, V. Tsurkan, V. Felea, A. Loidl, J. Cohn

{"title":"Magnetic field dependence of low-energy magnons, anisotropic heat conduction, and spontaneous relaxation of magnetic domains in the cubic helimagnet \u0000ZnCr2Se4","authors":"D. Inosov, Y. Onykiienko, Y. Tymoshenko, A. Akopyan, D. Shukla, N. Prasai, M. Doerr, D. Gorbunov, S. Zherlitsyn, D. Voneshen, M. Boehm, V. Tsurkan, V. Felea, A. Loidl, J. Cohn","doi":"10.1103/physrevb.102.184431","DOIUrl":"https://doi.org/10.1103/physrevb.102.184431","url":null,"abstract":"Anisotropic low-temperature properties of the cubic spinel helimagnet ZnCr2Se4 in the single-domain spin-spiral state are investigated by a combination of neutron scattering, thermal conductivity, ultrasound velocity, and dilatometry measurements. In an applied magnetic field, neutron spectroscopy shows a complex and nonmonotonic evolution of the spin-wave spectrum across the quantum-critical point that separates the spin-spiral phase from the field-polarized ferromagnetic phase at high fields. A tiny spin gap of the pseudo-Goldstone magnon mode, observed at wave vectors that are structurally equivalent but orthogonal to the propagation vector of the spin helix, vanishes at this quantum critical point, restoring the cubic symmetry in the magnetic subsystem. The anisotropy imposed by the spin helix has only a minor influence on the lattice structure and sound velocity but has a much stronger effect on the heat conductivities measured parallel and perpendicular to the magnetic propagation vector. The thermal transport is anisotropic at T < 2 K, highly sensitive to an external magnetic field, and likely results directly from magnonic heat conduction. We also report long-time thermal relaxation phenomena, revealed by capacitive dilatometry, which are due to magnetic domain motion related to the destruction of the single-domain magnetic state, initially stabilized in the sample by the application and removal of magnetic field. Our results can be generalized to a broad class of helimagnetic materials in which a discrete lattice symmetry is spontaneously broken by the magnetic order.","PeriodicalId":8511,"journal":{"name":"arXiv: Strongly Correlated Electrons","volume":"48 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75854007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

η-pairing in correlated fermion models with spin-orbit coupling 具有自旋-轨道耦合的相关费米子模型中的η对

arXiv: Strongly Correlated Electrons Pub Date : 2020-09-27 DOI: 10.1103/physrevb.102.165150

K. Li

{"title":"η\u0000-pairing in correlated fermion models with spin-orbit coupling","authors":"K. Li","doi":"10.1103/physrevb.102.165150","DOIUrl":"https://doi.org/10.1103/physrevb.102.165150","url":null,"abstract":"We generalize the $eta$-pairing theory in Hubbard models to the ones with spin-orbit coupling (SOC) and obtain the conditions under which the $eta$-pairing operator is an eigenoperator of the Hamiltonian. The $eta$ pairing thus reveals an exact $SU(2)$ pseudospin symmetry in our spin-orbit coupled Hubbard model, even though the $SU(2)$ spin symmetry is explicitly broken by the SOC. In particular, these exact results can be applied to a variety of Hubbard models with SOC on either bipartite or non-bipartite lattices, whose noninteracting limit can be a Dirac semimetal, a Weyl semimetal, a nodal-line semimetal, and a Chern insulator. The $eta$ pairing conditions also impose constraints on the band topology of these systems. We then construct and focus on an interacting Dirac-semimetal model, which exhibits an exact pseudospin symmetry with fine-tuned parameters. The stability regions for the emph{exact} $eta$-pairing ground states (with momentum $bm{pi}$ or $bm{0}$) and the emph{exact} charge-density-wave ground states are established. Between these distinct symmetry-breaking phases, there exists an exactly solvable multicritical line. In the end, we discuss possible experimental realizations of our results.","PeriodicalId":8511,"journal":{"name":"arXiv: Strongly Correlated Electrons","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80368993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7