Journal of Physics: Condensed Matter最新文献

{"title":"Strongly emerging octahedral modifications with Al doping and its influence on the electronic transport in NdNiO₃thin films.","authors":"Ketan S Navale, Diptanshu Basak, Ekta Yadav, Krushna R Mavani","doi":"10.1088/1361-648X/add2be","DOIUrl":"https://doi.org/10.1088/1361-648X/add2be","url":null,"abstract":"<p><p>The temperature-dependent electronic transport and the metal-insulator transition in ABO₃perovskite-type NdNiO₃are highly sensitive to chemical substitutions and lattice-mismatch induced strain in thin films. We synthesized two series of NdNi_1-<i>x</i>Al<i>_x</i>O₃(<i>x</i>= 0-0.50) thin films on LAO (001) single crystal substrates using the pulsed laser deposition technique: one with varied Al doping level (<i>x</i>= 0-0.50) and the other with fixed doping (<i>x</i>= 0.5) but different thickness (10-200 nm). Substituting Al at Ni-site modifies the Ni oxidation state, as observed by x-ray photoelectron spectroscopy. A Raman mode around 693 cm^-1emerges with just 2% Al-doping at the Ni-site, which is otherwise absent in undoped NdNiO₃film. This mode is associated with an anti-stretching of BO₆octahedra in perovskites. With increasing doping, this mode strongly emerges in a dominating manner in the spectra, clearly indicating a further enhancement of octahedral anti-stretching. This mode exhibits a blue shift with increasing Al doping and a red shift with increasing thickness at<i>x</i>= 0.50. Temperature-dependent Raman spectra, analyzed using Balkanski and Grüneisen models, reveal anharmonicity and Red-shifting behaviors. The undoped film shows a metal-to-insulator transition temperature (<i>T</i>_MI) of ∼77 K, which systematically increases with greater anti-stretching of octahedra and Al doping. At higher doping levels (<i>x</i>= 0.20 and 0.50), the films show insulating behavior below room temperature. As the thickness of NdNi_0.50Al_0.50O₃films varies from 10 nm to 200 nm, the anti-stretching mode got affected, resulting in systematic decrease in resistivity. Our findings confirm that the anti-stretching mode arises by Al doping, and it is associated with the insulating behavior of Al-doped NdNiO₃thin films.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 22","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144015584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Orientation-dependent superconductivity and electronic structure of the rare-earth metal/KTaO₃interfaces.","authors":"Guowei Yang, Weifan Zhu, Jiawen Zhang, Hao Zheng, Yi Wu, Huali Zhang, Ge Ye, Dajun Su, Yanan Zhang, Chao Cao, Xin Lu, Huiqiu Yuan, Yang Liu","doi":"10.1088/1361-648X/add2bf","DOIUrl":"https://doi.org/10.1088/1361-648X/add2bf","url":null,"abstract":"<p><p>The recent discovery of orientation-dependent superconductivity in KTaO₃-based interfaces has attracted considerable interest, while the underlying origin remains an open question. Here we report a different approach to tune the interfacial electron gas and superconductivity by forming interfaces between rare-earth (RE) metals (RE being La, Ce, Eu) and KTaO₃substrates with different orientations. We found that the interfacial superconductivity is strongest for the Eu/KTaO₃interfaces, becomes weaker in La/KTaO₃and is absent in Ce/KTaO₃. Using<i>in-situ</i>photoemission, we observed distinct valence bands associated with RE metals, as well as a pronounced orientation dependence in the interfacial electronic structure, which can be linked to the orientation-dependent superconductivity. The photoemission spectra show similar double-peak structures for the (111) and (110) oriented interfaces, with an energy separation close to the LO4 phonon of KTaO₃. Detailed analyses suggest that this double-peak structure could be attributed to electron-phonon coupling, which might be relevant for the interfacial superconductivity.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 21","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144004694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Optimally tuned range-separated hybrid van der Waals density functional for molecular binding and quasiparticle characterizations.","authors":"Elsebeth Schröder, Raul Quintero-Monsebaiz, Yang Jiao, Per Hyldgaard","doi":"10.1088/1361-648X/add0fd","DOIUrl":"https://doi.org/10.1088/1361-648X/add0fd","url":null,"abstract":"<p><p>We introduce and illustrate use of two closely related range-separated hybrid (RSH) van der Waals density functionals (vdW-DFs), denoted AHBR-mRSH and AHBR-mRSH*, for total-energy and quasiparticle characterizations of molecules using generalized Kohn-Sham (gKS) density functional theory (DFT). For comparison, we also introduce and document a traditional design for a long-range corrected (LRC) vdW-DF, denoted 'B86R-LRC'. All three new vdW-DFs set the exchange potential as free of asymptotic screening in the coupling between the electron and its associated exchange hole. Our two AHBR-mRSHs are key members of a broader class 'AHBR-mRSH(<i>γ</i>)' defined by an inverse length scale<i>γ</i>for a crossover in weighting short- and long-ranged exchange contributions; we obtain a highly accurate predictor of general molecular-energy differences by keeping<i>γ</i> = 0.106 (inverse Bohr) deliberately fixed in AHBR-mRSH. We obtain an optimally tuned (OT) form AHBR-mRSH* = AHBR-mRSH(γ∗) by computing a plausible value ofγ∗for specific types of systems. This AHBR-mRSH* permits characterizations of molecular quasiparticles and generalizes (1) the existing 'OT-RSH' (Stein<i>et al</i>2010<i>Phys. Rev. Lett.</i><b>105</b>266802; Rafaely-Abramson<i>et al</i>2012<i>Phys. Rev. Lett.</i><b>109</b>226405) approach by a systematic inclusion of truly nonlocal correlations, and (2) more traditional LRC forms (e.g. B86R-LRC) by setting the short-range exchange description as in vdW-DF2-ahbr (Shukla<i>et al</i>2022<i>Phys. Rev. X</i><b>12</b>041003).<i>Importantly,</i>we may view AHBR-mRSH and AHBR-mRSH* as internally consistent functionals for gKS-DFT, being simultaneously accurate on molecular energies and quasiparticles. This is possible because the 'AHBR-mRSH(<i>γ</i>)' class has enough transferability to almost always limit adverse impacts of tuning<i>γ</i>, as tested here on the GMTKN55 benchmark suite (Goerigk<i>et al</i>2017<i>Phys. Chem. Chem. Phys.</i><b>19</b>32184). We find that AHBR-mRSH generally outperforms B86R-LRC on molecular problems. To illustrate usage, we complete the OT design of an AHBR-mRSH* for nucleobases and show that it provides quasiparticle predictions that are in good agreement with both literature theory and experimental values for adenine, thymine, cytosine, and guanine.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 21","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143970771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Disorder impacts on transport and magnetoresistance properties in a gapless ferromagnetic/normal/ferromagnetic phosphorene junction.","authors":"Outmane Oubram, Isaac Rodríguez-Vargas, Eric Jovani Guzmán","doi":"10.1088/1361-648X/add070","DOIUrl":"https://doi.org/10.1088/1361-648X/add070","url":null,"abstract":"<p><p>The ballistic electronic transport and tunneling magnetoresistance (TMR) in a ferromagnetic/normal/ferromagnetic (F/N/F) gapless phosphorene junction have been investigated. This study focuses on the effects of structural disorder-specifically, variations in the width and height of the electrostatic potential barrier and magnetic field-on transport and TMR properties. A low-energy two-band Hamiltonian, derived from the tight-binding model along the armchair direction of phosphorene, is used. Transmission, conductance, and magnetoresistance are calculated using the transfer matrix technique, the Landauer-Büttiker formalism, and the TMR relation, respectively. The findings reveal that structural disorder related to barrier width reduces transmission oscillations and moderately suppresses conductance. A key result is that even slight combined structural disorder significantly degrades TMR properties in a gapless phosphorene F/N/F junction. Furthermore, maintaining transport properties, particularly TMR, in this device requires precise control over fluctuations in externally applied fields, especially the magnetic field.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 21","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144019110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"All-optical valley regulator based on nonlinear parametric scattering in monolayer transition metal dichalcogenides embedded in microcavity.","authors":"Mingjie Ye, Xinxin Gao, Chuanyi Zhang","doi":"10.1088/1361-648X/add2c1","DOIUrl":"https://doi.org/10.1088/1361-648X/add2c1","url":null,"abstract":"<p><p>In the field of valleytronics, significant advancements have been made in valley manipulation in linear optical processes. However, the exploration of relevant nonlinearity is crucial for developing coherent optical sources and signal processing in on-chip photonic devices, yet it remains relatively underexplored. Here we demonstrate all-optical valley regulation by leveraging nonlinear parametric scattering processes within monolayer transition metal dichalcogenides embedded in a semiconductor microcavity. Specifically, by utilizing three excitation laser beams (signal, pump, and idler lasers), we observe that the signals from both valleys can be synchronously amplified or suppressed by adjusting the phase of the pump laser. Remarkably, we can independently and effectively control the signals from each valley, with the amplification or suppression of either valley being regulated by the degree of circular polarization or phase difference between circularly polarized components of the pump laser. These advancements in all-optical valley manipulation deepen the understanding of nonlinear optical processes and thus facilitate their potential applications in opto-valleytronic devices.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 21","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143988121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Study on spin-dependent thermoelectric transport properties of graphene nanoribbon molecular devices modulated by DNA bases adsorption.","authors":"XiaoGe Peng, XiaoJiao Zhang, JinTao Xu, YueChao Shi, LiYuan Kou, MengQiu Long","doi":"10.1088/1361-648X/adcf6a","DOIUrl":"https://doi.org/10.1088/1361-648X/adcf6a","url":null,"abstract":"<p><p>This study employs density functional theory and non-equilibrium Green's function methods to investigate the thermoelectric and thermal spin transport properties of four molecular devices, which are constructed by four different DNA base molecules, adenine (A), guanine (G), cytosine (C), thymine (T), adsorbing on graphene nanoribbon (GNR). The research reveals that the Device-G and Device-C adsorption turn on a spin-down electron transport channel, resulting in a strongly spin-polarized current. When a temperature difference is applied at GNR electrodes, the values of thermoelectric both charge current and spin current follows the device sequence A < T < C < G. Further analysis indicates that the adsorption of base molecules on graphene substrates effectively enhances electronic conductance, with the thermoelectric performance of adsorbed G and C significantly surpassing those of A and T. This research provides insights into the potential of thermoelectric method for DNA bases recognition.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 21","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144010231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Re-investigation of moment direction in a Kitaev material<i>α</i>-RuCl₃.","authors":"Subin Kim, Ezekiel Horsley, Christie S Nelson, Jacob P C Ruff, Young-June Kim","doi":"10.1088/1361-648X/adcf6c","DOIUrl":"https://doi.org/10.1088/1361-648X/adcf6c","url":null,"abstract":"<p><p>We report x-ray diffraction and resonant elastic x-ray scattering studies on two<i>α</i>-RuCl₃crystals with distinct magnetic transition temperatures:TN = 7.3 K and 6.5 K. We find that the sample withTN = 6.5 K exhibits a high degree of stacking faults and structural twinning at low temperature, whereas theTN = 7.3 K sample primarily comprises a single domain of R3¯. Notwithstanding, both samples exhibit an identical zigzag magnetic structure, with magnetic moments pointing away from the honeycomb plane byα=31(2)∘. We argue that the identical ordered moment directions in these samples suggest that the intralayer magnetic interactions remain mostly unchanged regardless ofTN.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 21","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144031508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Low-temperature electron-electron interaction correction to the anomalous Hall effect in Fe₃GaTe₂single crystals.","authors":"Yihui Dong, Xiuming Long, Xiaowei Lv, Yalei Huang, Mingqian Zhang, Renchao Che, Guixin Cao","doi":"10.1088/1361-648X/adcb0f","DOIUrl":"https://doi.org/10.1088/1361-648X/adcb0f","url":null,"abstract":"<p><p>The electron-electron interaction (EEI), weak localization and Kondo effect are known to correct low-temperature (low-<i>T</i>) resistivity in metals and semimetals. However, the impact of EEI on the anomalous Hall effect (AHE) by EEI remains a subject of debate. In this study, we investigate the EEI corrections to both the low-<i>T</i>longitudinal and AH resistivities in van der Waals ferromagnetic Fe₃GaTe₂single crystals with a high Curie temperature. Our findings reveal that the longitudinal resistivity is well-described by the EEI theory developed by Altshuler<i>et al,</i>while the AH resistivity deviates from this theory. We found that the AH resistivity follows aTtemperature dependence, and its relative rate of change is 2.6 times that of the longitudinal resistivity. These results demonstrate that EEI significantly influences the low-<i>T</i>AH resistivity under intrinsic mechanism in Fe₃GaTe₂. This observation challenges the conventional understanding that EEI does not contribute to the AHE in systems with mirror symmetry, as suggested by skew scattering and side jump models. This work opens avenues for further exploration of EEI effect in disordered magnetic materials.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 21","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143997992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Spin-exchange induced spillover on poor man's Majoranas in minimal Kitaev chains.","authors":"J E Sanches, L T Lustosa, L S Ricco, H Sigurðsson, M de Souza, M S Figueira, E Marinho, A C Seridonio","doi":"10.1088/1361-648X/adce6a","DOIUrl":"https://doi.org/10.1088/1361-648X/adce6a","url":null,"abstract":"<p><p>The 'poor man's Majoranas' (PMMs) (Leijnse and Flensberg 2012<i>Phys. Rev. B</i><b>86</b>134528) devoid of topological protection can 'spill over' from one edge into another of the minimal Kitaev chain when perturbed electrostatically. As aftermath, this leads to a delocalized Majorana fermion (MF) at both the edges. Additionally, according to recent differential conductance measurements in a pair of superconducting and spinless quantum dots (QDs), such a PMM picture was brought to reality (Dvir<i>et al</i>2023<i>Nature</i><b>614</b>445; ten Haaf<i>et al</i>2024<i>Nature</i><b>630</b>329). Based on this scenario, we propose the spillover of the PMM when its QD is exchange coupled to a quantum spin<i>S</i>. We show that if this QD is perturbed by the exchange coupling<i>J</i>, solely the half2S+1(2S+2)of the fine structure stays explicit for a fermionic (bosonic)S.Concurrently, the other half squeezes itself as the delocalized MF zero-mode. Particularly, turning-off the superconductivity the multiplicity2S+1holds regardless the spin statistics. Meanwhile, the PMM spillover induced by<i>J</i>becomes a statistics dependent effect. Hence, our findings contribute to the comprehension of spin-phenomena interplay with superconductivity in minimal Kitaev chains, offering insights for future quantum computing devices hosting PMMs.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 20","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144025843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 quantitative relationship between electron localization function and the strength of physical binding.","authors":"Kim-Jonas Ylivainio, Ali Sufyan, J Andreas Larsson","doi":"10.1088/1361-648X/adcc70","DOIUrl":"https://doi.org/10.1088/1361-648X/adcc70","url":null,"abstract":"<p><p>The electron localization function (ELF) measures electron localization in matter and provides insights into bonds in materials and molecules. This study examines the relationship between ELF and binding energy in bimolecular systems, focusing on van der Waals (vdW) interactions such as Keesom, Debye, and London dispersion forces. These interactions play significant roles in crystalline molecular materials. This work addresses the challenge of accurately calculating binding energies in molecular materials and supramolecular synthons by exploring their correlation with ELF. We use density functional theory and have evaluated seven exchange-correlation functionals to identify which functional provides the most accurate binding energies in comparison to values obtained with coupled cluster. The findings revealed that rev-vdW-DF2 offers high precision, whereas Perdew-Burke-Ernzerhof-D3(BJ) is computationally efficient. These functionals were utilized to demonstrate how ELF can be employed to accurately determine binding energies. By analyzing the ELF and its correlation with binding energies in 95 bimolecular systems held together with physical bindings ranging from weak to strong interactions, we demonstrate a strong linear correlation, with a coefficient of determination (<i>R</i>²) reaching 0.960. These findings suggest that ELF can effectively differentiate between weak and strong vdW interactions, providing a reliable quantitative metric for evaluating interaction strengths. The results indicate that ELF can be used as method to determine the strength of intermolecular interactions, with potential applications in materials science. Especially as a method for analyzing and predicting molecular interaction strengths within molecular materials and supramolecular synthons. This work opens up the possibility to derive all directional physical binding energies of molecular materials within the unit cell directly from the ELF, which has the potential to simplify practical calculations. Furthermore, the study revealed a possible systematic error for current xc-functionals in describing systems with two neighboring O-H⋯O hydrogen bonds between interacting molecules.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 20","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143998228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}