Journal of Physics: Condensed Matter最新文献

{"title":"Exploring the correlation between chemical bonding and structural distortions in TbCu_0.33Te₂.","authors":"Leander Weinelt, Simon Steinberg","doi":"10.1088/1361-648X/ada411","DOIUrl":"https://doi.org/10.1088/1361-648X/ada411","url":null,"abstract":"<p><p>The design of solid-state materials requests a thorough understanding of the structural preferences among plausible structure models. Since the bond energy contributes to the formation energy of a given structure model, it also is decisive to determine the nature of chemical bonding for a given material. In this context, we were motivated to explore the correlation between chemical bonding and structural distortions within the low-dimensional tellurium fragments in TbCu_0.33Te₂. The ternary telluride was obtained from high-temperature solid-state reactions, while structure determinations based on x-ray diffraction experiments did not point to the presence of any structural distortion above 100 K. However, the results of first-principles-based computations indicate that a potential structural distortion within the low-dimensional tellurium fragments also correlates to an optimization of overall bonding.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 11","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007274","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":"Reinvestigating atomic ordering inK0.5Na0.5NbO3and its impact on ferroelectric properties.","authors":"Anuvrat Tripathi, Saurabh Tripathi","doi":"10.1088/1361-648X/ada65d","DOIUrl":"https://doi.org/10.1088/1361-648X/ada65d","url":null,"abstract":"<p><p>In the present work, we reinvestigate the atomic ordering of a Pb-free morphotropic phase boundary (MPB) compositionviz.,K0.5Na0.5NbO3(KNN50) and its vicinity at various length scales using high-resolution x-ray diffraction and pair distribution function data. We have observed a monoclinic phase (Space Group: Pm) at long/short ranges differing from a very recent report by Saha<i>et al</i>2024<i>J. Phys.: Condens. Matter</i><b>36</b>425703. Moreover, the ferroelectric (polarization) dominance of short-range ordering (SRO) over long-range ordering (LRO) has been observed and quantified for the very first time using the amplitude of the ferroelectric frozen phonon mode (Γ4-) (corresponding to the high symmetry cubic phase), thereby structure is linked with ferroelectric (or polarization) property for a widely studied MPB systemviz.,KxNa(1-x)NbO3(KNN<i>x</i>for<i>x</i>= 0.40, 0.50, and 0.60). Two uniquely identified monoclinic phases has been observed for SRO (MSRO) and LRO (MLRO) for all the compositions. The amplitude of ferroelectric frozen phonon mode (Γ4-) corresponding toMSROis significantly higher (≈150%-180%) thanMLRO. A peak is observed in the amplitude ofΓ4-and intensity of prominent Raman peaks (<i>ν</i>₁and<i>ν</i>₅) for<i>x</i>= 0.50, which is held responsible for high physical propertiesviz.,dielectric permittivity, piezoelectric coefficient, remnant polarization, electromechanical coupling coefficient, and many more widely reported in literature for KNN50.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 11","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007279","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":"Spectral heat flux redistribution upon interfacial transmission.","authors":"Haoran Cui, Theodore Maranets, Tengfei Ma, Yan Wang","doi":"10.1088/1361-648X/ada660","DOIUrl":"https://doi.org/10.1088/1361-648X/ada660","url":null,"abstract":"<p><p>In nonmetallic crystals, heat is transported by phonons of different frequencies, each contributing differently to the overall heat flux spectrum. In this study, we demonstrate a significant redistribution of heat flux among phonon frequencies when phonons transmit across the interface between dissimilar solids. This redistribution arises from the natural tendency of phononic heat to re-establish the bulk distribution characteristic of the material through which it propagates. Remarkably, while the heat flux spectra of dissimilar solids are typically distinct in their bulk forms, they can become nearly identical in superlattices or sandwich structures where the layer thicknesses are smaller than the phonon mean free paths. This phenomenon reflects that the redistribution of heat among phonon frequencies to the bulk distribution does not occur instantaneously at the interface, rather it develops over a distance on the order of phonon mean-free-paths.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 11","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007281","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":"Collective modes in terahertz field response of disordered superconductors.","authors":"Yantao Li, Maxim Dzero","doi":"10.1088/1361-648X/ada65e","DOIUrl":"https://doi.org/10.1088/1361-648X/ada65e","url":null,"abstract":"<p><p>We consider a problem of nonlinear response to an external electromagnetic radiation in conventional disordered superconductors which contain a small amount of weak magnetic impurities. We focus on the diffusive limit and use Usadel equation to analyze the excitation energy and dispersion relation of the collective modes. We determine the resonant frequency and dispersion of both amplitude (Schmidt-Higgs) and phase (Carlson-Goldman) modes for moderate strength of magnetic scattering. We find that the minimum energy required for the excitation of the both of these modes decreases with an increase in spin-flip scattering. Surprisingly we also find that as a result the Carlson-Goldman mode becomes gapless and as a consequence can only be excited at some finite value of the threshold momentum. We thus discover yet another physical realization of a state with gapped momentum dispersion of one of its collective modes. The value of the threshold momentum is determined by the distance between the two consecutive spin-flip scattering events which, in turn, is proportional to the scattering time between two consecutive scattering events. The amplitude mode is diffusive and becomes strongly suppressed with the increase in spin-flip scattering. Possible ways to experimentally verify our results are also discussed.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 11","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007271","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":"Beyond the random phase approximation for calculating Curie temperatures in ferromagnets: application to Fe, Ni, Co and monolayer CrI₃.","authors":"Varun Rajeev Pavizhakumari, Thorbjørn Skovhus, Thomas Olsen","doi":"10.1088/1361-648X/ada65c","DOIUrl":"https://doi.org/10.1088/1361-648X/ada65c","url":null,"abstract":"<p><p>The magnetic properties of solids are typically analyzed in terms of Heisenberg models where the electronic structure is approximated by interacting localized spins. However, even in such models the evaluation of thermodynamic properties constitutes a major challenge and is usually handled by a mean field decoupling scheme. The random phase approximation (RPA) comprises a common approach and is often applied to evaluate critical temperatures although it is well known that the method is only accurate well<i>below</i>the critical temperature. In the present work we compare the performance of the RPA with a different decoupling scheme proposed by Callen as well as the mean field decoupling of interacting Holstein-Primakoff (HP) magnons. We consider three-dimensional (3D) as well as two-dimensional (2D) model systems where the Curie temperature is governed by anisotropy. In 3D, the Callen method is the most accurate in the classical limit, and we show that the Callen decoupling (CD) produces the best agreement with experiments for bcc Fe, fcc Ni and fcc Co with exchange interactions obtained from first principles. In contrast, for low spin systems where a quantum mechanical treatment is pertinent, the HP and RPA methods are superior to the CD. In 2D systems with magnetic order driven by single-ion anisotropy, it is shown that HP fails rather dramatically and both RPA and Callen approaches severely overestimates Curie temperatures. The most accurate approach is then constructed by combining RPA with the CD of single-ion anisotropy, which yields the correct lack of order forS=1/2. We exemplify this by the case of monolayer CrI₃using exchange constant extracted from experiments.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 11","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007270","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":"Intriguing magnetic and electronic behaviors in La and Ru doped Sr₂IrO₄.","authors":"B Dundi Sri Chandana, Jeetendra Kumar Tiwari, K Saranya, Arpita Rana, G Senthil Murugan, Namasivayam Dhenadhayalan, Kwang-Yong Choi, K C Sekhar, P D Babu, Raman Sankar, I Panneer Muthuselvam","doi":"10.1088/1361-648X/ada47a","DOIUrl":"10.1088/1361-648X/ada47a","url":null,"abstract":"<p><p>We report a detailed experimental study of the structural, magnetic and electrical properties of La and Ru doped (Sr_1-<i>x</i>La<i>_x</i>)₂Ir_1-<i>x</i>Ru<i>_x</i>O₄(<i>x</i>= 0.05, 0.15). X-ray diffraction analysis reveals that both samples crystallize in a tetragonal structure with a space group<i>I</i>4₁/<i>acd</i>without impurities. Substitution with La and Ru leads to an increase in the lattice parameter<i>a</i>and a decrease in<i>c</i>. With increasing doping concentration, the Ir-O-Ir bond angle increases while the Ir-O bond length decreases. X-ray photoelectron spectroscopy (XPS) shows that Ir has Ir³⁺(5<i>d</i>⁶) and Ir⁴⁺(5<i>d</i>⁵) charge states, where the Ir⁴⁺charge state decreases with an increase in doping concentration. The<i>dc</i>magnetic susceptibility<i>χ</i>(<i>T</i>) of<i>x</i>= 0.05 reveals a transition from paramagnetic to weak ferromagnetic (wFM) at<i>T</i>_C∼ 229 K, arising from the canted antiferromagnetic (AFM) spin arrangement. The magnetic ordering temperature<i>T</i>_Cremains unaltered for higher doping, whereas the magnetic moment is significantly reduced. The analysis of real and imaginary components of<i>ac</i>susceptibility data, based on conventional critical slow model, frequency shift per decade and Vogel-Fulcher law, unanimously evidences the existence of reentrant spin-glass behavior (RSG), i.e. the coexistence of weak ferromagnetism and spin glass phases for the lowest doping of<i>x</i>= 0.05. On the other hand, for higher doping (<i>x</i>= 0.15) of hole and electron, the RSG phase vanishes, leaving only the wFM phase at the same temperature as observed in<i>x</i>= 0.05. This suggests the higher doping of La and Ru does not affect the magnetic order, but removes the disorder between FM and AFM phases. The electrical resistivity (<i>ρ</i>) measurement analysis reveals that both the samples show semiconducting/insulating behavior across the temperature range. The<i>ρ</i>of the<i>x</i>= 0.05 sample is lower than that of pure sample Sr₂IrO₄(Bhatti<i>et al 2015 J. Phys.:Condens. Matter</i><b>27</b>016005), while<i>ρ</i>of<i>x</i>= 0.15 shows two orders of magnitude larger than the<i>x</i>= 0.05 sample at low temperatures. The conduction mechanism of both samples is described by the 2D Mott's variable-range hopping model. Our results demonstrate that co-doping of two cation sites generates intriguing, competing hopping and magnetic processes.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142908866","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":"The spin-wave energy spectrum and transition temperature of the two-dimensional VSe₂-like: a retarded Green's function method study.","authors":"Da-Cheng Ma, Xiao-Dan Chi, Sheng Gao, Chu-Xiao Sun, Ling-Yi Cui, An Du","doi":"10.1088/1361-648X/ada678","DOIUrl":"https://doi.org/10.1088/1361-648X/ada678","url":null,"abstract":"<p><p>Based on the recent discovery of intrinsic magnetism in monolayer films VSe₂, we have constructed a two-dimensional (2D) Heisenberg model incorporating the 1<i>T</i>and 2<i>H</i>structures. These configurations consist of three layers: the upper and lower surface layers and a middle layer. Using the retarded Green's function method, we investigate the spin-wave energy spectrum, spin-wave density of states, and transition temperature of the system. It is found that in the 2<i>H</i>structure, the spin-wave energy spectrum of the system exhibits three direct energy gaps, with one branch being independent of the wave vector. Further analysis shows that at this constant energy, a particular surface state emerges in the 2<i>H</i>structure. In contrast, the spin-wave energy spectrum in the 1<i>T</i>structure features only two energy gaps-one direct energy gap1 and one indirect energy gap3-without forming a unique surface state. Single-ion anisotropy and interlayer interactions between the upper and lower surface layers influence the energy gaps in the spin-wave energy spectrum and the system's transition temperature. This theoretical work sheds light on forming particular surface states in monolayer 2<i>H</i>structure magnetic materials. It provides crucial theoretical support for designing and fabricating next-generation low-dimensional magnetic random-access memory.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 11","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007285","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":"2D biphenylene: exciting properties, synthesis & applications.","authors":"Vinod Kumar, Surender Pratap, Brahmananda Chakraborty","doi":"10.1088/1361-648X/ada70f","DOIUrl":"10.1088/1361-648X/ada70f","url":null,"abstract":"<p><p>In the current era of nanotechnology, the isolation of graphene has acted as a catalyst for the study and creation of many innovative two-dimensional (2D) materials with distinctive functions. The recent synthesis of biphenylene (BPN), a porous 2D carbon allotrope, has ignited significant research interest due to its unique and tunable properties, making it a promising candidate for diverse applications in hydrogen storage, batteries, sensing, electrocatalysis, and beyond. Although a considerable amount of research has been carried out on BPN, there is hardly any review article on this fascinating material. Therefore, this comprehensive review article focuses on the fascinating properties of the advanced graphene family and 2D BPN. Additionally, there has been an in-depth discussion on 2D BPN, covering its synthesis process, recent advancements, and its applications in various fields. Moreover, this review will be useful to professionals and researchers in materials science, physics, chemistry, chemical engineering, and related subjects since it provides detailed information on the characteristics, synthesis, and applications of 2D BPN.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142950577","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":"Potential magnetic structure in Eu₃InAs₃revealed by magnetization and thermodynamic study.","authors":"Ming Liu, Shuai Zhang, Ke Jia, Zhaotong Zhuang, Xinyang Liu, Yaqiang Ma, Junsen Xiang, Youguo Shi, Peijie Sun","doi":"10.1088/1361-648X/ada661","DOIUrl":"https://doi.org/10.1088/1361-648X/ada661","url":null,"abstract":"<p><p>We systematically investigate the magnetization and thermodynamic responses associated with the antiferromagnetic (AFM) transitions in magnetic semiconductor Eu₃InAs₃. The linear thermal expansion measurements reveal that<i>a</i>axis expands whereas<i>b</i>and<i>c</i>axes contract with the onset of the two AFM transitions atTN1andTN2. Using a simplified mean-field model incorporating AFM exchange interactions, easy-axis anisotropy, and Zeeman coupling, we analyze the potential magnetic structure change associated with the spin-flop and spin-flip transitions in field. The agreement between experimental and calculated magnetization data suggests that the1/3plateau along<i>b</i>axis results from a partial spin-flip transition in a multiple-easy-axis magnetic structure, where Eu₂-Eu₃and Eu₁sublattices order antiferromagnetically along the<i>b</i>and<i>a</i>axes atTN1andTN2, respectively. Consistently, field dependence of magnetic entropy determined using low-<i>T</i>adiabatic magnetocaloric effect indicates that the number of the ordered Eu²⁺moments atTN1is nearly twice that atTN2. Our results demonstrate that the magnetic structure in materials with strong spin-lattice coupling can be simply approached by a combined magnetization and thermodynamic study.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":"37 11","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143007278","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":"Anomalous and large topological Hall effects in<i>β</i>-Mn chiral compound Co_6.5Ru_1.5Zn₈Mn₄: electron electron interaction facilitated quantum interference effect.","authors":"Afsar Ahmed, Arnab Bhattacharya, I Das","doi":"10.1088/1361-648X/ada59f","DOIUrl":"10.1088/1361-648X/ada59f","url":null,"abstract":"<p><p><i>β</i>-Mn-type chiral cubic Co_<i>x</i>Zn_<i>y</i>Mn_<i>z</i>(<i>x</i>+<i>y</i>+<i>z</i>= 20) alloys present a intriguing platform for exploring topological magnetic orderings with promising spintronic potential. This study examines the magnetotransport properties of Co_6.5Ru_1.5Zn₈Mn₄, a skyrmion-hosting<i>β</i>-Mn-type chiral compound. The longitudinal resistivity (<i>ρ</i>_<i>xx</i>) exhibits field-insensitive low-temperature minima due to quantum interference effects, driven byT1/2-dependent electron-electron interactions. We observe a substantial intrinsic anomalous Hall conductivity, unaffected by quantum interference. Additionally, a pronounced topological Hall effect is observed at the metastable skyrmionic state, persisting up toTCand achieving notable magnitudes for stoichiometric compounds. These results position the Co_<i>x</i>Zn_<i>y</i>Mn_<i>z</i>family favourably to leverage the rich pallete of emergent magnetotransport properties for spintronic applications.</p>","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142927400","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}