Structural Dynamics-Us最新文献

Discovery of a new zinc oxide semiconductor: 21R polytype. 一种新型氧化锌半导体的发现：21R多型。

IF 2.3 2区物理与天体物理

Structural Dynamics-Us Pub Date : 2025-03-27 eCollection Date: 2025-03-01 DOI: 10.1063/4.0000296

Matej Fonović, Jelena Zagorac, Maria Čebela, Dragana Jordanov, Dejan Zagorac

{"title":"Discovery of a new zinc oxide semiconductor: 21R polytype.","authors":"Matej Fonović, Jelena Zagorac, Maria Čebela, Dragana Jordanov, Dejan Zagorac","doi":"10.1063/4.0000296","DOIUrl":"10.1063/4.0000296","url":null,"abstract":"Zinc oxide (ZnO) is a notable semiconductor with a range of interesting electronic and optical properties. Polytypic behavior of crystal structures can strongly affect the properties of materials, especially in ZnO. We report the first prediction of a new 21R polytype in zinc oxide with advanced properties. Ab initio calculations were carried out using two-hybrid functionals: HSE06 and PBE0. Structural properties of different ZnO polytypes were investigated, and theoretical data concurred with experimental results. This can be further exploited for various applications based on their unique properties. Electronic properties were studied using band structures and density of states (DOS). Present DFT calculations agree very well with previous calculations and measurements of known ZnO polytypes, and the new 21R polytype is found as a direct band gap semiconductor. The size of the band gap in the case of the hybrid HSE06 functional is calculated to be 2.79 eV and with PBE0 is 3.42 eV. Understanding the structure-property relationship helps in tailoring ZnO for specific applications and optimizing its performance in various technological contexts, especially as an advanced semiconductor material, with possible applications such as 0D, 1D, 2D, and 3D materials.","PeriodicalId":48683,"journal":{"name":"Structural Dynamics-Us","volume":"12 2","pages":"024101"},"PeriodicalIF":2.3,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11952831/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143755285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Probing optically driven K₃C₆₀ thin films with an ultrafast voltmeter. 利用超快电压计探测光驱动 K3C60 薄膜。

IF 2.3 2区物理与天体物理

Structural Dynamics-Us Pub Date : 2025-03-26 eCollection Date: 2025-03-01 DOI: 10.1063/4.0000295

J D Adelinia, E Wang, M Chavez-Cervantes, T Matsuyama, M Fechner, M Buzzi, G Meier, A Cavalleri

{"title":"Probing optically driven K3C60 thin films with an ultrafast voltmeter.","authors":"J D Adelinia, E Wang, M Chavez-Cervantes, T Matsuyama, M Fechner, M Buzzi, G Meier, A Cavalleri","doi":"10.1063/4.0000295","DOIUrl":"10.1063/4.0000295","url":null,"abstract":"Optically enhanced superconductivity in K3C60 is supported by transient optical spectra, by pressure responses, and by ultrafast nonlinear transport measurements. However, the underlying physics and in fact the similarity or dissimilarity to most properties of equilibrium superconductivity are not clear. In this paper, we study the ultrafast voltage response of optically driven K3C60 thin films. Photo-conductive switches are used to measure changes in voltage as a function of time after irradiation, both below and above Tc. These measurements can be understood if one considers the role of granularity in the photo-induced transport response. They reveal fast voltage changes associated with the kinetic inductance of the in-grain carriers and a slower response that may be attributed to Josephson dynamics at the weak links. Fits to the data yield estimates of the in-grain photo-induced superfluid density after the drive and the dynamics of phase slips at the weak links. This work underscores the increasing ability to make electrical measurements at ultrafast speeds in optically driven quantum materials and demonstrates a striking new platform for optoelectronic device applications.","PeriodicalId":48683,"journal":{"name":"Structural Dynamics-Us","volume":"12 2","pages":"024503"},"PeriodicalIF":2.3,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11949515/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143732695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Magnetization dynamics: From the Landau-Lifschitz equation to spintronics. 磁化动力学：从朗道-利夫希茨方程到自旋电子学。

IF 2.3 2区物理与天体物理

Structural Dynamics-Us Pub Date : 2025-03-25 eCollection Date: 2025-03-01 DOI: 10.1063/4.0000290

Yves Acremann

引用次数: 0

Simultaneous mapping of the ultrafast time and fluence dependence of the laser-induced insulator-to-metal transition in magnetite. 磁铁矿中激光诱导绝缘体到金属跃迁的超快时间和通量依赖关系的同步映射。

IF 2.3 2区物理与天体物理

Structural Dynamics-Us Pub Date : 2025-03-20 eCollection Date: 2025-03-01 DOI: 10.1063/4.0000288

J O Schunck, P S Miedema, R Y Engel, S Dziarzhytski, G Brenner, N Ekanayake, C-F Chang, P Bougiatioti, F Döring, B Rösner, C David, C Schüßler-Langeheine, M Beye

{"title":"Simultaneous mapping of the ultrafast time and fluence dependence of the laser-induced insulator-to-metal transition in magnetite.","authors":"J O Schunck, P S Miedema, R Y Engel, S Dziarzhytski, G Brenner, N Ekanayake, C-F Chang, P Bougiatioti, F Döring, B Rösner, C David, C Schüßler-Langeheine, M Beye","doi":"10.1063/4.0000288","DOIUrl":"10.1063/4.0000288","url":null,"abstract":"Pump-probe methods are a ubiquitous tool in the field of ultrafast dynamic measurements. In recent years, x-ray free-electron laser experiments have gained importance due to their ability to probe with high chemical selectivity and at atomic length scales. Measurements are typically repeated many thousands of times to collect sufficient statistics and vary parameters like delay or fluence, necessitating that initial conditions are restored each time. An alternative is presented by experiments which measure the relevant parameters in a single shot. Here, we present a time-to-space mapping imaging scheme that enables us to record a range of delays and laser fluences in any single shot of the x-ray probe. We demonstrate the use of this scheme by mapping the ultrafast dynamics of the optically induced insulator-to-metal Verwey transition in a magnetite thin film, probed by soft x-ray resonant diffraction. By extrapolating our results toward the conditions found at x-ray free-electron lasers with higher photon energy, we demonstrate that the presented data could be recorded in a single shot.","PeriodicalId":48683,"journal":{"name":"Structural Dynamics-Us","volume":"12 2","pages":"024302"},"PeriodicalIF":2.3,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11928099/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143694127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Ultrafast-induced coherent acoustic phonons in the two-dimensional magnet CrSBr. 二维磁体 CrSBr 中的超快诱导相干声子。

IF 2.3 2区物理与天体物理

Structural Dynamics-Us Pub Date : 2025-03-20 eCollection Date: 2025-03-01 DOI: 10.1063/4.0000266

Jayajeewana N Ranhili, Sumit Khadka, Junjie Li, John Cenker, Alberto M Ruiz, Andrei Shumilin, José J Baldoví, Ka Shen, Mikhail Fedurin, Mark Palmer, Daniel G Chica, Paul Byaruhanga, Shuo Chen, Xiaodong Xu, Xavier Roy, Byron Freelon

{"title":"Ultrafast-induced coherent acoustic phonons in the two-dimensional magnet CrSBr.","authors":"Jayajeewana N Ranhili, Sumit Khadka, Junjie Li, John Cenker, Alberto M Ruiz, Andrei Shumilin, José J Baldoví, Ka Shen, Mikhail Fedurin, Mark Palmer, Daniel G Chica, Paul Byaruhanga, Shuo Chen, Xiaodong Xu, Xavier Roy, Byron Freelon","doi":"10.1063/4.0000266","DOIUrl":"10.1063/4.0000266","url":null,"abstract":"Magnetism in two-dimensional (2D) van der Waals (vdW) crystals offers promising new directions for low-dimensional physics and devices. In this work, mega-electron volt (MeV) ultrafast electron diffraction was employed to investigate the ultrafast atomic dynamics of a novel, 2D vdW magnetic single-crystal CrSBr. Femtosecond (fs) optical pump pulses excited non-equilibrium atomic displacements shown to be coherent acoustic phonons (CAPs). Phonon frequencies were extracted by analyzing oscillations of different Bragg peak (BP) intensities and were determined to be GHz acoustic disturbances that propagated as strain waves. Phonon modes exhibit anisotropy with respect to the a and b crystal axes. Subharmonic phonon frequencies were also observed, and this provided a signature of nonlinear oscillatory coupling between the laser-induced pumping phonon frequency and secondary phonon frequencies. Thus, CrSBr was found to serve as a nonlinear phononic frequency converter. The ultrafast time dependence of the Bragg intensity was simulated by incorporating an oscillating deviation parameter ansatz into expressions for the dynamical scattering intensity yielded excellent modeling of the ultrafast structural dynamics of the photo-excited 2D crystal. Our work provides a foundation for exploring how fs light pulses can influence phonon dynamics in materials with strong spin-lattice coupling. These results suggest that CAPs can match the magnon frequencies and show the promise of CrSBr for use in optical-to-microwave transducers and phononic devices.","PeriodicalId":48683,"journal":{"name":"Structural Dynamics-Us","volume":"12 2","pages":"024501"},"PeriodicalIF":2.3,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11928097/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143694050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Implementation and performance of a fiber-coupled CMOS camera in an ultrafast reflective high-energy electron diffraction experiment. 光纤耦合CMOS相机在超快反射高能电子衍射实验中的实现与性能。

IF 2.3 2区物理与天体物理

Structural Dynamics-Us Pub Date : 2025-03-06 eCollection Date: 2025-03-01 DOI: 10.1063/4.0000284

Jonas D Fortmann, Alexander Kaßen, Christian Brand, Thomas Duden, Michael Horn-von Hoegen

{"title":"Implementation and performance of a fiber-coupled CMOS camera in an ultrafast reflective high-energy electron diffraction experiment.","authors":"Jonas D Fortmann, Alexander Kaßen, Christian Brand, Thomas Duden, Michael Horn-von Hoegen","doi":"10.1063/4.0000284","DOIUrl":"10.1063/4.0000284","url":null,"abstract":"The implementation of a monolithic fiber-optically coupled CMOS-based TemCam-XF416 camera into our ultra-high vacuum (UHV) ultrafast reflection high-energy electron diffraction setup is reported. A combination of a pumpable gate valve and a self-built cooling collar allows UHV conditions to be reached without the need to remove the heat-sensitive device. The water-cooled collar is mounted to the camera housing and prevents heating of the camera upon bakeout of the UHV chamber. The TemCam possesses an one order of magnitude higher spatial resolution, which provides 30% higher resolution in reciprocal space than the previously used microchannel plate detector. The low background intensity and the four times larger dynamic range enable analysis of the diffuse intensity of the diffraction pattern like Kikuchi lines and bands. A key advantage over the previous MCP detector is the complete absence of the blooming effect, which enables the quantitative spot profile analysis of the diffraction spots. The inherent light sensitivity in an optical pump experiment can be overcome by subtracting a pump image without a probe, using photons with <math><mrow><mi>h</mi> <mi>ν</mi> <mo><</mo> <mn>1.12</mn></mrow> </math> eV (indirect bandgap of silicon), or shielding any stray light.","PeriodicalId":48683,"journal":{"name":"Structural Dynamics-Us","volume":"12 2","pages":"024301"},"PeriodicalIF":2.3,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11888785/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143587659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Sharing our excitement for structural science through mentorship. 通过指导分享我们对结构科学的兴奋。

IF 2.3 2区物理与天体物理

Structural Dynamics-Us Pub Date : 2025-02-10 eCollection Date: 2025-01-01 DOI: 10.1063/4.0000285

Gerald F Audette

引用次数: 0

Time-resolved x-ray absorption spectroscopy probe in ultrafast surface chemistry. 超快表面化学中时间分辨x射线吸收光谱探针。

IF 2.3 2区物理与天体物理

Structural Dynamics-Us Pub Date : 2025-02-05 eCollection Date: 2025-01-01 DOI: 10.1063/4.0000289

Anders Nilsson

引用次数: 0

Whither the protein landscape? 蛋白质的前景在哪里？

IF 2.3 2区物理与天体物理

Structural Dynamics-Us Pub Date : 2025-02-05 eCollection Date: 2025-01-01 DOI: 10.1063/4.0000291

Charles W Carter, George N Phillips

引用次数: 0

Non-equilibrium states and interactions in the topological insulator and topological crystalline insulator phases of NaCd₄As₃. NaCd4As3拓扑绝缘体和拓扑晶体绝缘体相的非平衡态及其相互作用。

IF 2.3 2区物理与天体物理

Structural Dynamics-Us Pub Date : 2025-02-05 eCollection Date: 2025-01-01 DOI: 10.1063/4.0000273

Tika R Kafle, Yingchao Zhang, Yi-Yan Wang, Xun Shi, Na Li, Richa Sapkota, Jeremy Thurston, Wenjing You, Shunye Gao, Qingxin Dong, Kai Rossnagel, Gen-Fu Chen, James Freericks, Henry C Kapteyn, Margaret M Murnane

{"title":"Non-equilibrium states and interactions in the topological insulator and topological crystalline insulator phases of NaCd4As3.","authors":"Tika R Kafle, Yingchao Zhang, Yi-Yan Wang, Xun Shi, Na Li, Richa Sapkota, Jeremy Thurston, Wenjing You, Shunye Gao, Qingxin Dong, Kai Rossnagel, Gen-Fu Chen, James Freericks, Henry C Kapteyn, Margaret M Murnane","doi":"10.1063/4.0000273","DOIUrl":"10.1063/4.0000273","url":null,"abstract":"Topological materials are of great interest because they can support metallic edge or surface states that are robust against perturbations, with the potential for technological applications. Here, we experimentally explore the light-induced non-equilibrium properties of two distinct topological phases in NaCd4As3: a topological crystalline insulator (TCI) phase and a topological insulator (TI) phase. This material has surface states that are protected by mirror symmetry in the TCI phase at room temperature, while it undergoes a structural phase transition to a TI phase below 200 K. After exciting the TI phase by an ultrafast laser pulse, we observe a leading band edge shift of >150 meV that slowly builds up and reaches a maximum after ∼0.6 ps and that persists for ∼8 ps. The slow rise time of the excited electron population and electron temperature suggests that the electronic and structural orders are strongly coupled in this TI phase. It also suggests that the directly excited electronic states and the probed electronic states are weakly coupled. Both couplings are likely due to a partial relaxation of the lattice distortion, which is known to be associated with the TI phase. In contrast, no distinct excited state is observed in the TCI phase immediately or after photoexcitation, which we attribute to the low density of states and phase space available near the Fermi level. Our results show how ultrafast laser excitation can reveal the distinct excited states and interactions in phase-rich topological materials.","PeriodicalId":48683,"journal":{"name":"Structural Dynamics-Us","volume":"12 1","pages":"014501"},"PeriodicalIF":2.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11811906/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143400393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0