Journal of Physics Communications最新文献_第4页

Application of Jacobi stability analysis to a first-order dynamical system: relation between nonlinearizability of one-dimensional differential equation and Jacobi stable region 雅可比稳定性分析在一阶动力系统中的应用：一维微分方程的非线性化与雅可比稳定区域之间的关系

IF 1.2

Journal of Physics Communications Pub Date : 2024-03-05 DOI: 10.1088/2399-6528/ad2b8c

Yuma Hirakui, Takahiro Yajima

{"title":"Application of Jacobi stability analysis to a first-order dynamical system: relation between nonlinearizability of one-dimensional differential equation and Jacobi stable region","authors":"Yuma Hirakui, Takahiro Yajima","doi":"10.1088/2399-6528/ad2b8c","DOIUrl":"https://doi.org/10.1088/2399-6528/ad2b8c","url":null,"abstract":"In this study, we discuss Jacobi stability in equilibrium and nonequilibrium regions for a first-order one-dimensional system using deviation curvatures. The deviation curvature is calculated using the Kosambi-Cartan-Chern theory, which is applied to second-order differential equations. The deviation curvatures of the first-order one-dimensional differential equations are calculated using two methods as follows. Method 1 is only differentiating both sides of the equation. Additionally, Method 2 is differentiating both sides of the equation and then substituting the original equation into the second-order system. From the general form of the deviation curvatures calculated using each method, the analytical results are obtained as (A), (B), and (C). (A) Equilibrium points are Jacobi unstable for both methods; however, the type of equilibrium points is different. In Method 1, the equilibrium point is a nonisolated fixed point. Conversely, the equilibrium point is a saddle point in Method 2. (B) When there is a Jacobi stable region, the size of the Jacobi stable region in the Method 1 is different from that in Method 2. Especially, the Jacobi stable region in Method 1 is always larger than that in Method 2. (C) When there are multiple equilibrium points, the Jacobi stable region always exists in the nonequilibrium region located between the equilibrium points. These results are confirmed numerically using specific dynamical systems, which are given by the logistic equation and its evolution equation with the Hill function. From the results of (A) and (B), differences in types of equilibrium points affect the size of the Jacobi stable region. From (C), the Jacobi stable regions appear as nonequilibrium regions where the equations cannot be linearized.","PeriodicalId":47089,"journal":{"name":"Journal of Physics Communications","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140312030","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: 0

Ab initio study of p- and n-type doping of two-dimensional MoO2: investigation of a pn-homojunction 二维 MoO2 的 p 型和 n 型掺杂的 Ab initio 研究：pn-homojunction 的研究

IF 1.2

Journal of Physics Communications Pub Date : 2024-02-16 DOI: 10.1088/2399-6528/ad2a41

Kevin Ndang Amassa, A. J. Etindele, D. H. Douma, S. Kenmoe, Chetty Nithaya

{"title":"Ab initio study of p- and n-type doping of two-dimensional MoO2: investigation of a pn-homojunction","authors":"Kevin Ndang Amassa, A. J. Etindele, D. H. Douma, S. Kenmoe, Chetty Nithaya","doi":"10.1088/2399-6528/ad2a41","DOIUrl":"https://doi.org/10.1088/2399-6528/ad2a41","url":null,"abstract":"\u0000 Based on density functional theory, we studied the effect of p- and n-type doping on the structural and electronic properties of MoO2 monolayers and bilayers. We used niobium (Nb) and nitrogen (N) as p-type dopants, and technetium (Tc) and fluorine (F) as n-type dopants through atomic substitutions. Our study shows that the presence of a substituent in the 4 × 4 supercell of MoO2 leads to a slight distortion and negligible modification of the lattice parameter. Both p- and n-type doped monolayers exhibit a metallic character. The bilayers obtained by vertically stacking n-p doped monolayers all exhibit a metallic character, as their band diagrams do not show a band gap. The study of their charge difference highlights a physisorption phenomenon. This type of material, which features a nucleophilic site in the p-doped region and an electrophilic site in the n-doped region, is a promising candidate for catalysis. When n-type and p-type doped monolayers are horizontally joined, the resulting stack exhibits a semi- conductor behavior.The special feature of this stacking is that we obtain a true pn junction, that is a space charge zone associated with a potential jump. For its application in infrared junction diodes, we have demonstrated both quantitatively and qualitatively the existence of a potential jump at the junction.","PeriodicalId":47089,"journal":{"name":"Journal of Physics Communications","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139960341","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: 0

Inkjet-printed quantum dots on paper as concept towards high-density long-term data storage 纸张上的喷墨打印量子点是实现高密度长期数据存储的概念

IF 1.2

Journal of Physics Communications Pub Date : 2024-02-12 DOI: 10.1088/2399-6528/ad246d

Nils Mengel, Marius Welzel, Woldemar Niedenthal, Markus Stein, Dominik Heider, Sangam Chatterjee

{"title":"Inkjet-printed quantum dots on paper as concept towards high-density long-term data storage","authors":"Nils Mengel, Marius Welzel, Woldemar Niedenthal, Markus Stein, Dominik Heider, Sangam Chatterjee","doi":"10.1088/2399-6528/ad246d","DOIUrl":"https://doi.org/10.1088/2399-6528/ad246d","url":null,"abstract":"Handling and storing the immense amounts of data native to the information age is a major challenge in terms of technological sustainability and energy demand. To date, tape storage remains the most widespread method for data archiving, while DNA data storage appears to offer the best data density and long-term stability in the future. However, DNA data storage is still in its infancy primarily due to economic and accessibility challenges. This emphasizes the need for more practical and readily available alternatives. We present a method for data storage utilizing inkjet printable quantum dots on paper with photoluminescence (PL) readout. Our proof of principle study showcases the ability to print and stack multiple bits of data on a single spot by exploiting the unique PL properties of quantum dots. This approach utilizes easily accessible resources, including a consumer-grade printer and paper as the substrate. Additionally, we perform initial stability tests, investigate scalability by controlling emission intensity, and evaluate the potential data density achievable by our approach.","PeriodicalId":47089,"journal":{"name":"Journal of Physics Communications","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139767864","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: 0

Electron density analysis of two-electron systems confined by prolate spheroids with hard walls 由硬壁增大球体限制的双电子系统的电子密度分析

IF 1.2

Journal of Physics Communications Pub Date : 2024-02-12 DOI: 10.1088/2399-6528/ad246e

Heichi Yanajara-Parra, Adalberto Corella-Madueño, F Adrián Duarte-Alcaraz, Rubicelia Vargas, Jorge Garza

{"title":"Electron density analysis of two-electron systems confined by prolate spheroids with hard walls","authors":"Heichi Yanajara-Parra, Adalberto Corella-Madueño, F Adrián Duarte-Alcaraz, Rubicelia Vargas, Jorge Garza","doi":"10.1088/2399-6528/ad246e","DOIUrl":"https://doi.org/10.1088/2399-6528/ad246e","url":null,"abstract":"The electron density of two-electron systems, He and H<sub>2</sub>, was analyzed when prolate spheroids with hard walls confine these systems. For this purpose, Hartree–Fock equations were solved using Roothaan's approach with a basis set defined in prolate spheroidal coordinates imposing Dirichlet boundary conditions. Total energy, its components, and orbital energies were analyzed for several confinements, and some of these results were compared with those reported by other authors to test the performance of the proposed approach. For both systems, the electron density exhibits a maximum value out of the nuclear region for extreme confinements. The chemical bond for H<sub>2</sub> was analyzed through the concepts of the quantum theory of atoms in molecules, concluding that the chemical bond of this molecule disappears under extreme conditions. For this system, estimations of the correlation energy indicate that this is a small contribution to the total energy, and the Hartree–Fock method contains the necessary elements to describe the chemical bond for strong confinements.","PeriodicalId":47089,"journal":{"name":"Journal of Physics Communications","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139767882","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: 0

An autoencoder for heterotic orbifolds with arbitrary geometry 具有任意几何形状的异质轨道折叠的自动编码器

IF 1.2

Journal of Physics Communications Pub Date : 2024-02-09 DOI: 10.1088/2399-6528/ad246f

Enrique Escalante–Notario, Ignacio Portillo–Castillo, Saúl Ramos–Sánchez

引用次数: 0

Nanocomposite materials as observed by mass-selective neutron spectroscopy 通过质量选择性中子能谱观测纳米复合材料

IF 1.2

Journal of Physics Communications Pub Date : 2024-02-09 DOI: 10.1088/2399-6528/ad27e0

M. Krzystyniak, Giovanni Romanelli, Beata Grabowska, Felix Fernandez-Alonso

{"title":"Nanocomposite materials as observed by mass-selective neutron spectroscopy","authors":"M. Krzystyniak, Giovanni Romanelli, Beata Grabowska, Felix Fernandez-Alonso","doi":"10.1088/2399-6528/ad27e0","DOIUrl":"https://doi.org/10.1088/2399-6528/ad27e0","url":null,"abstract":"\u0000 This work provides a current, critical view of the application of MAss- selective Neutron SpEctroscopy (MANSE) to nanocomposite materials. MANSE is a unique technique made possible owing to the existence of the pulsed neutron sources. At present, the only operating MANSE spectrometer in the world, VESUVIO, is located at the ISIS Neutron and Muon Source in the UK. We start by providing a brief description of the neutron Compton scattering, the anatomy of a mass-selective neutron spectrometer, and the experimental data treatment. We continue by brieﬂy outlining the main quantum mechanical concepts, models and approximations relevant both to the ab initio prediction and experimental measurement of main MANSE observables. Next, we present several recent exemplars chosen to highlight the use of MANSE in the ﬁeld of nanocomposites. Our examples include, in chronological order, encapsulated nanoparticles in amorphous silica gel, bioactive glass-ionomer cement, Cu-Ti-C composites, and sodium carboxymethyl starch-based binders in the presence of a mineral matrix. We close by providing our view of the ongoing and future challenges and opportunities in the mass-selective neutron investigation of NQEs in nanocomposite materials.","PeriodicalId":47089,"journal":{"name":"Journal of Physics Communications","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139788111","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: 0

Nanocomposite materials as observed by mass-selective neutron spectroscopy 通过质量选择性中子能谱观测纳米复合材料

IF 1.2

Journal of Physics Communications Pub Date : 2024-02-09 DOI: 10.1088/2399-6528/ad27e0

M. Krzystyniak, Giovanni Romanelli, Beata Grabowska, Felix Fernandez-Alonso

{"title":"Nanocomposite materials as observed by mass-selective neutron spectroscopy","authors":"M. Krzystyniak, Giovanni Romanelli, Beata Grabowska, Felix Fernandez-Alonso","doi":"10.1088/2399-6528/ad27e0","DOIUrl":"https://doi.org/10.1088/2399-6528/ad27e0","url":null,"abstract":"\u0000 This work provides a current, critical view of the application of MAss- selective Neutron SpEctroscopy (MANSE) to nanocomposite materials. MANSE is a unique technique made possible owing to the existence of the pulsed neutron sources. At present, the only operating MANSE spectrometer in the world, VESUVIO, is located at the ISIS Neutron and Muon Source in the UK. We start by providing a brief description of the neutron Compton scattering, the anatomy of a mass-selective neutron spectrometer, and the experimental data treatment. We continue by brieﬂy outlining the main quantum mechanical concepts, models and approximations relevant both to the ab initio prediction and experimental measurement of main MANSE observables. Next, we present several recent exemplars chosen to highlight the use of MANSE in the ﬁeld of nanocomposites. Our examples include, in chronological order, encapsulated nanoparticles in amorphous silica gel, bioactive glass-ionomer cement, Cu-Ti-C composites, and sodium carboxymethyl starch-based binders in the presence of a mineral matrix. We close by providing our view of the ongoing and future challenges and opportunities in the mass-selective neutron investigation of NQEs in nanocomposite materials.","PeriodicalId":47089,"journal":{"name":"Journal of Physics Communications","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139848158","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: 0

Optimal control of large quantum systems: assessing memory and runtime performance of GRAPE 大型量子系统的优化控制：评估 GRAPE 的内存和运行性能

IF 1.2

Journal of Physics Communications Pub Date : 2024-02-08 DOI: 10.1088/2399-6528/ad22e5

Yunwei Lu, Sandeep Joshi, Vinh San Dinh, Jens Koch

引用次数: 0

Information bottleneck in peptide conformation determination by x-ray absorption spectroscopy 利用 X 射线吸收光谱确定肽构象的信息瓶颈

IF 1.2

Journal of Physics Communications Pub Date : 2024-02-07 DOI: 10.1088/2399-6528/ad1f73

Eemeli A Eronen, Anton Vladyka, Florent Gerbon, Christoph J Sahle, Johannes Niskanen

{"title":"Information bottleneck in peptide conformation determination by x-ray absorption spectroscopy","authors":"Eemeli A Eronen, Anton Vladyka, Florent Gerbon, Christoph J Sahle, Johannes Niskanen","doi":"10.1088/2399-6528/ad1f73","DOIUrl":"https://doi.org/10.1088/2399-6528/ad1f73","url":null,"abstract":"We apply a recently developed technique utilizing machine learning for statistical analysis of computational nitrogen K-edge spectra of aqueous triglycine. This method, the emulator-based component analysis, identifies spectrally relevant structural degrees of freedom from a data set filtering irrelevant ones out. Thus tremendous reduction in the dimensionality of the ill-posed nonlinear inverse problem of spectrum interpretation is achieved. Structural and spectral variation across the sampled phase space is notable. Using these data, we train a neural network to predict the intensities of spectral regions of interest from the structure. These regions are defined by the temperature-difference profile of the simulated spectra, and the analysis yields a structural interpretation for their behavior. Even though the utilized local many-body tensor representation implicitly encodes the secondary structure of the peptide, our approach proves that this information is irrecoverable from the spectra. A hard x-ray Raman scattering experiment confirms the overall sensibility of the simulated spectra, but the predicted temperature-dependent effects therein remain beyond the achieved statistical confidence level.","PeriodicalId":47089,"journal":{"name":"Journal of Physics Communications","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139767619","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: 0

Mathematical diversity of parts for a continuous distribution 连续分布的部件数学多样性

IF 1.2

Journal of Physics Communications Pub Date : 2024-02-02 DOI: 10.1088/2399-6528/ad2560

R. Rajaram, N. Ritchey, Brian C. Castellani

{"title":"Mathematical diversity of parts for a continuous distribution","authors":"R. Rajaram, N. Ritchey, Brian C. Castellani","doi":"10.1088/2399-6528/ad2560","DOIUrl":"https://doi.org/10.1088/2399-6528/ad2560","url":null,"abstract":"\u0000 The current paper is part of a series exploring how to link diversity measures (e.g., Gini-Simpson index, Shannon entropy, Hill numbers) to a distribution's original shape and to compare parts of a distribution, in terms of diversity, with the whole. This linkage is crucial to understanding the exact relationship between the density of an original probability distribution, denoted by $p(x)$, and the diversity $D$ in non-uniform distributions, both within parts of a distribution and the whole. This linkage is empirically useful because most real-world systems have unequal distributions and consist of multiple diversity types with unknown and changing frequencies at different levels of scale (e.g., income diversity, economic complexity indices, rankings). To date, we have proven our results for discrete distributions. Our focus here is continuous distributions. In both instances, we do so by linking case-based entropy, a diversity approach we developed, to a probability distribution’s shape for continuous distributions. This allows us to demonstrate that the original probability distribution $g_1$, the case-based entropy curve $g_2$, and the slope of diversity $g_3$ ($c_{(a,x)}$ versus the $c_{(a,x)}* ln A_{(a,x)}$ curve) are one-to-one (or injective). In other words, a different probability distribution $g_1$, results in different curves for $g_2$, and $g_3$. Therefore, a different permutation of the original probability distribution (resulting in a different shape) will uniquely determine the graphs $g_2$ and $g_3$. By proving our approach’s injective nature for continuous distributions, we establish a unique method to measure the degree of uniformity as measured by $D/c$ and show a unique way to compute $D/c$ for various shapes of the original continuous distribution to compare different distributions and their parts.","PeriodicalId":47089,"journal":{"name":"Journal of Physics Communications","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139683444","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: 0