The European Physical Journal D最新文献

{"title":"Impact on polymeric surface of PMMA and PVC using argon atmospheric pressure plasma jet","authors":"Rasmil Asharaf,&nbsp;Vikas M. Shelar,&nbsp;Sanket Patil,&nbsp;R. S. Bharath","doi":"10.1140/epjd/s10053-026-01241-9","DOIUrl":"10.1140/epjd/s10053-026-01241-9","url":null,"abstract":"<div><p>Plasma treatment is a potent technique for altering surface properties of polymer without changing its bulk characteristics. In this study, polyvinyl chloride (PVC) and poly(methyl methacrylate) (PMMA) are treated using argon gas-based APPJ. The effect of plasma exposure times on the surface morphology and optical behavior was examined. Surface texture and roughness was measured by atomic force microscope (AFM), indicating the nanoetching effect and restructuring of surface using plasma. Surface degradation in both polymers is significantly evident from UV–Vis spectra. These findings were further verified by FT-IR analysis. Water contact angle measurements indicate a shift toward increased wettability of the surface as a function of surface plasma exposure time.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":"80 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148751461","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":"Correction: High-harmonic generation simulations as a classical barrier-traversal diagnostic in strong-field ionization","authors":"Amol R. Holkundkar","doi":"10.1140/epjd/s10053-026-01228-6","DOIUrl":"10.1140/epjd/s10053-026-01228-6","url":null,"abstract":"","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":"80 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148751268","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":"Terahertz optics of a few-electron gas in a strongly prolate ellipsoidal quantum dot: implementation of the Calogero model","authors":"I. Safaryan,&nbsp;M. Mkrtchyan,&nbsp;T. Hakobyan,&nbsp;H. Sarkisyan","doi":"10.1140/epjd/s10053-026-01214-y","DOIUrl":"10.1140/epjd/s10053-026-01214-y","url":null,"abstract":"<div><p>This article analytically investigates long-wavelength transitions in a highly prolate ellipsoidal quantum dot containing a pair-interacting electron gas. Given the quantum dot’s specific geometry, the problem is initially considered within the adiabatic approximation. The interaction between electrons is assumed to be pairwise and one-dimensional (in axial direction). It is shown that for the slow subsystem describing the gas states along the elongated semiaxis of the ellipsoid, the multiparticle Schrödinger equation contains, on the one side, a parabolic constraint potential for each electron and, on the other side, a term describing the pairwise interaction energy between electrons. The interparticle interaction operator is considered within the framework of the exactly solvable Calogero model, which allows one to separate the center-of-mass motion from the relative motion, thereby demonstrating the realization of the generalized Kohn theorem under the action of long-wavelength radiation.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":"80 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148751269","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":"Effect of semi-infinite confinement on forbidden radiative transitions in an oscillator-shaped quantum well","authors":"E. B. Al,&nbsp;E. I. Jafarov,&nbsp;A. M. Jafarova,&nbsp;F. Ungan","doi":"10.1140/epjd/s10053-026-01230-y","DOIUrl":"10.1140/epjd/s10053-026-01230-y","url":null,"abstract":"<p>We study the influence of a semi-infinite confinement, attached to an oscillator-shaped quantum well on its dipole and quadrupole radiation properties. The effect of semi-infinite confinement is achieved thanks to the use of the position-dependent mass formalism. The time-independent Schrödinger equation describing the system is exactly solvable in the configuration representation, and the corresponding wave functions are expressed in terms of Laguerre polynomials. A remarkable property of the model is that its discrete energy spectrum coincides exactly with the linear spectrum of the non-relativistic harmonic oscillator. Additionally, such a confined quantum system preserves its exact solvability even in the presence of an applied homogeneous external field. This allows both dipole and quadrupole radiation characteristics to be calculated analytically despite the simultaneous presence of the modified confinement profile and the external perturbation. Analytical expressions for the dipole and quadrupole moment matrix elements are obtained in terms of the confinement parameter and the external field strength. We analyze the dependence of these matrix elements and the corresponding radiation intensities on both parameters. In particular, although the discrete energy spectrum remains unchanged, the confinement effect transforms transitions that are forbidden in the harmonic oscillator – namely <span>(Delta n=pm 1)</span> and <span>(Delta n=0)</span> in dipole radiation and <span>(Delta n= pm 2)</span> in quadrupole radiation–into allowed ones. In the presence of the external homogeneous field, the confinement effect further modifies these transitions by introducing an explicit dependence on the field strength. Finally, we derive limiting relations showing that the model reduces to the standard non-relativistic harmonic oscillator when the confinement parameter tends to infinity and the external homogeneous field vanishes.\u0000</p>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":"80 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148751267","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":"Plasmonic layer induced enhanced photoluminescence in reactively sputtered copper (I) oxide thin films for potential optoelectronic application","authors":"Chinmoy Rajak,&nbsp;Subhamay Pramanik,&nbsp;Sandip Das,&nbsp;Gopinath Roy,&nbsp;Rajib Nath,&nbsp;Probodh K. Kuiri","doi":"10.1140/epjd/s10053-026-01229-5","DOIUrl":"10.1140/epjd/s10053-026-01229-5","url":null,"abstract":"<div><p>Metal-semiconductor hybrid nano-heterostructures have been under extensive study owing to their potential applications in optoelectronic devices, biosensing etc. In this study, glass/Ag/Cu₂O layered thin film heterostructures with varying thickness of the top Cu₂O layer were fabricated by reactive magnetron sputtering technique. While X-ray diffraction and Raman spectroscopy establish the formation of the aforesaid structure, detailed analysis of the surface morphology was performed by statistical analysis of atomic force microscopy images. The UV–visible absorption spectra of the samples reveal systematic increment in the absorbance with increasing thickness of the Cu₂O layer. A significant enhancement in photoluminescence (PL) intensity of up to 400% in the near UV region and about 300% in the violet–blue region of the electromagnetic spectrum was observed in the sample containing the thinnest Cu₂O layer, compared to the bare Cu₂O reference sample, for 300 nm and 350 nm excitation wavelengths. We attribute this enhancement to surface plasmon induced interfacial charge transfer between the Ag and Cu₂O layers. For samples with thicker Cu₂O layer, however, no such PL enhancement is observed due to the evanescent nature of the surface plasmon resonance effect. The observed enhancement in photoluminescence (PL) is of significant importance for modern electronic applications as it provides a promising pathway for the development and optimization of advanced optoelectronic devices.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div><div><p>Plasmonic Ag layer induced photoluminescence enhancement in glass/Ag/Cu_₂O nano-heterostructures</p></div></div></figure></div></div>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":"80 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148750969","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":"Focused electron beam-induced deposition from Ru(CO)₄(fumaronitrile): incomplete carbonyl loss and nitrogen retention","authors":"Chinmai Sai Jureddy,&nbsp;Atul Chaudhary,&nbsp;Rashmi Singh,&nbsp;Lisa McElwee-White,&nbsp;Ivo Utke","doi":"10.1140/epjd/s10053-026-01225-9","DOIUrl":"10.1140/epjd/s10053-026-01225-9","url":null,"abstract":"<div><p>The additive manufacturing of metal nanostructures using direct-write focused electron beam-induced deposition (FEBID) requires exploration and development of new metal-coordinated precursor complexes. In this study, we introduce (<i>η</i>²-fumaronitrile)(tetracarbonyl)ruthenium(0), a novel FEBID precursor designed using a mechanism-based approach in which the ligand set consists of neutral two-electron donor ligands weakly bound to the metal centre atom. Nanostructures were fabricated using this precursor via FEBID, and their elemental composition was determined through energy-dispersive X-ray spectroscopy. The resulting deposits consistently exhibited a metal content in the range of 8–12 at.%, highlighting the need for a deeper understanding of the role of competing mechanisms preventing detached neutral ligands from desorption during the FEBID process.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div><div><p>Fate of (<i>η</i>²-fumaronitrile)(tetracarbonyl)ruthenium in the focused electron-beam induced deposits</p></div></div></figure></div></div>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":"80 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13437608/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148681373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of bending parameters on crystalline undulator radiation peak stability for 530 MeV positron channelling","authors":"Matthew D. Dickers,&nbsp;Felipe Fantuzzi,&nbsp;Nigel J. Mason,&nbsp;Andrei V. Korol,&nbsp;Andrey V. Solov’yov","doi":"10.1140/epjd/s10053-026-01227-7","DOIUrl":"10.1140/epjd/s10053-026-01227-7","url":null,"abstract":"<p>We investigate the stability of crystalline undulator radiation (CUR) peaks emitted by 530 MeV positron channelling in periodically bent C(110) crystals with varying bending amplitudes and bending periods. Relativistic molecular dynamics simulations were performed to quantify how these parameters affect the intensity and position of the CUR peak. The continuous potential approximation was used to identify isolines of constant peak energy, providing a reference for regions of spectral stability. MD results show that increasing the bending amplitude shifts the CUR peak to lower photon energies, while decreasing the period shifts it to higher energies, with both trends accompanied by enhanced dechannelling. For crystal parameters similar to recent experiments conducted at the Mainz Mikrotron (MAMI), the simulated CUR peak appears near 0.515 MeV. These results demonstrate that the CUR peak remains stable across a broad range of bending amplitudes and periods, providing quantitative estimates of the sensitivity of the emitted radiation to variations in the crystal bending parameters.</p><p>Spectral distributions of crystalline undulator radiation for 530 MeV positrons for different bending profiles. The top row corresponds to the emission cone <span>(theta _0={133.8,mathrm{upmu text {rad}}}approx 0.139/gamma )</span>, and the bottom row <span>(5/gamma approx {4821,mathrm{upmu text {rad}}})</span>. The left column corresponds to a bending period of <span>(lambda ={8.0},upmu {textrm{m}})</span>, the middle column <span>({6.5},upmu {textrm{m}})</span>, and the right column <span>({5.0},upmu {textrm{m}})</span>. All cases show the same range of bending amplitudes a.</p>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":"80 8","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjd/s10053-026-01227-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148628711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plasma conditions for high-intensity (He^{2+}) beams: a semi-empirical modeling approach","authors":"G. Castro,&nbsp;L. Celona,&nbsp;C. Camonita,&nbsp;O. Leonardi,&nbsp;S. Gammino","doi":"10.1140/epjd/s10053-026-01224-w","DOIUrl":"10.1140/epjd/s10053-026-01224-w","url":null,"abstract":"<div><h3>Semi-empirical modeling of He2+ production in an ECR ion source shows that the extracted He2+ current is mainly governed by electron temperature, electron density and ion confinement time, with optimal performance obtained for high-density plasmas, electron temperatures above 100 eV, and intermediate confinement times (200 - 400 <span>(mu )</span>s)</h3><p>There is a growing interest in high-current <span>(He^{2+})</span> ion beams due to their potential applications in advanced medical treatments and frontier research. Meeting the requirements of such beams calls for a quantitative understanding of how plasma parameters affect charge-state production and extracted current, providing useful guidance for the design of next-generation helium ion sources. This study introduces a semi-empirical model to evaluate the plasma conditions required for efficient <span>(He^{2+})</span> production in an electron cyclotron resonance ion source. The model is based on the solution of a nonlinear set of helium particle balance equations, including the most relevant ionization and recombination processes, and allows the extracted <span>(He^{2+})</span> current to be estimated as a function of the main plasma parameters. The analysis shows that intense <span>({He}^{2+})</span> beam production requires electron temperatures above approximately 100 <i>eV</i> together with plasma densities of at least <span>(2-3cdot 10^{12}~{cm^{-3}})</span>. Confinement times of about <span>(200-400~mu {s})</span> are found to provide a favorable compromise between charge-state enhancement and extracted current. Overall, the proposed framework identifies the plasma regimes that favor intense <span>(He^{2+})</span> extraction and provides a practical tool to support the optimization of ion-source performance for medical and fundamental-science applications.</p><h3>Graphical abstract</h3><p>Semi-empirical modeling of <span>(He^{2+})</span> production in an ECR ion source shows that the extracted <span>(He^{2+})</span> current is mainly governed by electron temperature, electron density and ion confinement time, with optimal performance obtained for high-density plasmas, electron temperatures above 100 <i>eV</i>, and intermediate confinement times (<span>(200-400 mu {s})</span>).</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":"80 7","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148614519","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":"Classification of coined quantum walks on the line and comparison to correlated classical random walks","authors":"Lukas Hantzko,&nbsp;Lennart Binkowski","doi":"10.1140/epjd/s10053-026-01217-9","DOIUrl":"10.1140/epjd/s10053-026-01217-9","url":null,"abstract":"<p>We present a comprehensive classification of one-dimensional coined quantum walks on the infinite line, focusing on the spatial probability distributions they induce. Building on prior results, we identify all initial coin states that lead to symmetric quantum walks for arbitrary coins and provide a bijective parametrisation of all symmetric quantum walks modulo distributional equivalence. Extending beyond the symmetric case, we also give a surjective parametrisation of all coined quantum walks under the same equivalence relation, as well as a bijective parametrisation modulo equivalence of their limiting distributions. Furthermore, we derive corrected closed-form expressions for the walk amplitudes, resolving inaccuracies in previous literature, and generalise the approach to the correlated classical random walk. This unified framework enables a direct comparison between quantum and classical dynamics. Additionally, we discuss the asymptotic scaling of variances for both models, identifying quadratic spreading as a hallmark of non-trivial quantum walks and contrasting it with the linear behaviour of classical walks, except at the extremal points of maximal correlation. Finally, we compare the limiting distributions arising from quantum walks with those of the classical case.</p><p>- compact classification results for symmetric and general quantum walks, as well as classically correlated random walks - quantum walks spread ballistically while classically correlated random walks approach Gaussian limiting distribution - quantum coin parameter directly influence limiting distribution’s skewness</p>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":"80 7","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjd/s10053-026-01217-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148613671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A four-body calculation of the radiative dissociation of excited positronium molecules","authors":"Naoki Kamiya,&nbsp;Takuma Yamashita,&nbsp;Yasushi Kino","doi":"10.1140/epjd/s10053-026-01206-y","DOIUrl":"10.1140/epjd/s10053-026-01206-y","url":null,"abstract":"<p>This study reports a four-body calculation of the radiative dissociation of positronium molecules (<span>(mathrm {Ps_2})</span>) in an excited state. The excited state of <span>(mathrm {Ps_2})</span> lies between the Ps (<span>(n=1)</span>) + Ps (<span>(n=1)</span>) and Ps (<span>(n=1)</span>) + Ps (<span>(n=2)</span>) thresholds and spontaneously dissociates into Ps (<span>(n=1)</span>) + Ps (<span>(n=1)</span>) through an electric dipole transition accompanied by photon emission. The energy spectrum and dissociation rates are calculated using a complex coordinate rotation method within the dipole approximation. The total radiative dissociation rate is <span>(0.044 mathrm {ns^{-1}})</span>, which is one order of magnitude smaller than that of the electric dipole transition to the ground state of <span>(mathrm {Ps_2})</span>. The branching ratio of the radiative dissociation among the all spontaneous decay modes, including annihilation, has been determined to be 1.5%.</p>","PeriodicalId":789,"journal":{"name":"The European Physical Journal D","volume":"80 7","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjd/s10053-026-01206-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148613903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}