Journal of Physics B: Atomic, Molecular and Optical Physics最新文献_第6页

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-03-18 DOI: 10.1088/1361-6455/ad2e2f

Nilakantha Meher

引用次数: 0

Charge exchange of slow highly charged ions from an electron beam ion trap with surfaces and 2D materials 来自电子束离子阱的慢速高电荷离子与表面和二维材料的电荷交换

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-03-18 DOI: 10.1088/1361-6455/ad2e2a

A Niggas, M Werl, F Aumayr, R A Wilhelm

引用次数: 0

Using ‘designer’ coherences to control electron transfer in a model bis(hydrazine) radical cation: can we still distinguish between direct and superexchange mechanisms? 利用 "设计者 "相干性控制双（肼）自由基阳离子模型中的电子转移：我们还能区分直接交换机制和超交换机制吗？

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-03-14 DOI: 10.1088/1361-6455/ad2e31

Mercè Deumal, Jordi Ribas-Ariño, Michael A Robb

{"title":"Using ‘designer’ coherences to control electron transfer in a model bis(hydrazine) radical cation: can we still distinguish between direct and superexchange mechanisms?","authors":"Mercè Deumal, Jordi Ribas-Ariño, Michael A Robb","doi":"10.1088/1361-6455/ad2e31","DOIUrl":"https://doi.org/10.1088/1361-6455/ad2e31","url":null,"abstract":"We have simulated two mechanisms, direct and superexchange, for the electron transfer in a <italic toggle=\"yes\">model Bis(hydrazine) Radical Cation</italic>, which consists of two hydrazine moieties coupled by a benzene ring. The computations, that are inspired by the attochemistry approach, focus on the electron dynamics arising from a coherent superposition of four cationic states. The electron dynamics, originating from a solution of the time dependent Schrödinger equation within the Ehrenfest method, is coupled to the relaxation of the nuclei. Both direct (<italic toggle=\"yes\">ca</italic>. 15 fs dynamics) and superexchange (<italic toggle=\"yes\">ca.</italic> 2 fs dynamics) mechanisms are observed and turn out to lie on a continuum depending on the strength of the coupling of the benzene bridge electron dynamics with the hydrazine chromophore dynamics. This contrasts with the chemical pathway approach where the direct mechanism is completely non-adiabatic via a conical intersection, while the superexchange mechanism involves an intermediate radical with the unpaired electron localized on the benzene ring. Thus, with the attochemistry-inspired electron dynamics approach, one can distinguish direct from superexchange mechanisms depending on the strength of the coupling of two types of electron dynamics: the slow hydrazine dynamics (<italic toggle=\"yes\">ca</italic>. 15 fs) and the fast benzene linker dynamics (<italic toggle=\"yes\">ca.</italic> 2 fs). In this model bis(hydrazine) radical cation, only when the intermediate coupler is in an anti-quinoid state, does one see the coupling of the bridge and hydrazine chromophore dynamics.","PeriodicalId":16826,"journal":{"name":"Journal of Physics B: Atomic, Molecular and Optical Physics","volume":"37 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140316089","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}

引用次数: 0

Both experimental and molecular dynamics approaches highlight the central role of interfacial water for radical production by irradiated gold nanoparticles 实验和分子动力学方法都强调了界面水在辐照金纳米粒子产生自由基过程中的核心作用

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-03-13 DOI: 10.1088/1361-6455/ad2e28

Emilie Brun, Rika Tandiana, Manon Gilles, Yannis Cheref, Nguyen-Thi Van-Oanh, Carine Clavaguera, Cécile Sicard-Roselli

{"title":"Both experimental and molecular dynamics approaches highlight the central role of interfacial water for radical production by irradiated gold nanoparticles","authors":"Emilie Brun, Rika Tandiana, Manon Gilles, Yannis Cheref, Nguyen-Thi Van-Oanh, Carine Clavaguera, Cécile Sicard-Roselli","doi":"10.1088/1361-6455/ad2e28","DOIUrl":"https://doi.org/10.1088/1361-6455/ad2e28","url":null,"abstract":"Nanoparticles devoted to improve radiotherapy treatments are an efficient tool if they can induce the formation of deleterious species in the tumor. Their interaction with radiation is responsible for radical production but in spite of the numerous studies mostly with cells, no consensus has been reached about radical formation mechanism. In order to gain knowledge in the physico-chemical step of this phenomenon, we applied a very sensitive test to quantify hydroxyl radicals and electrons produced when gold atoms, organized as nanoparticles or as a salt in solution, are irradiated by keV and MeV photons (x- and <italic toggle=\"yes\">γ</italic>- rays). The crucial role of interfacial water is suggested to explain the high quantity of radicals measured for nanoparticles. These experimental data were supplemented by classical molecular dynamics simulations, revealing a specific organization of the water hydrogen bonding network at the nanoparticle surface which could be a key component in the mechanism of radical production by irradiated colloidal suspensions.","PeriodicalId":16826,"journal":{"name":"Journal of Physics B: Atomic, Molecular and Optical Physics","volume":"37 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140316246","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}

引用次数: 0

Production and protection of entanglement via vacuum induced coherences 通过真空诱导相干产生和保护纠缠

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-03-13 DOI: 10.1088/1361-6455/ad2d5d

Anjali N Nair, R Arun

引用次数: 0

High harmonic generation in monolayer indium nitride 单层氮化铟中的高次谐波生成

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-03-12 DOI: 10.1088/1361-6455/ad2e2e

Xiaoyu Liu, Zhiqiang Ji, Chenglong Wu, Shasha Li, Hong Wu, Feng Li, Yong Pu

引用次数: 0

Controllable single-photon transport mediated by a time-modulated Jaynes–Cummings model 由时间调制杰尼斯-康明斯模型介导的可控单光子传输

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-03-12 DOI: 10.1088/1361-6455/ad2e2b

Haozhen Li, Yang Lan, Ran Zeng, Miao Hu, Mengmeng Xu, Xiuwen Xia, Jingping Xu, Yaping Yang

{"title":"Controllable single-photon transport mediated by a time-modulated Jaynes–Cummings model","authors":"Haozhen Li, Yang Lan, Ran Zeng, Miao Hu, Mengmeng Xu, Xiuwen Xia, Jingping Xu, Yaping Yang","doi":"10.1088/1361-6455/ad2e2b","DOIUrl":"https://doi.org/10.1088/1361-6455/ad2e2b","url":null,"abstract":"Controllable single-photon scattering in a one-dimensional waveguide coupled to a Jaynes–Cummings structure containing a time-modulated two-level atom interacting with a single-mode cavity is investigated. The photon transmission and reflection amplitudes are calculated by using an effective Floquet Hamiltonian in real space. The results show that the coupling between the atom and the cavity mode can dynamically be tuned via periodically modulating the atomic transition frequency. As a consequence, the scattering behaviors of the waveguide photons can be actively manipulated, and a controllable single-photon switch with high on-off ratio could be realized. More interestingly, the switch works well within a wide frequency region, i.e., the transmission of both resonant and off-resonant waveguide photons can be effectively switched on or off with appropriate system parameters. Furthermore, the proposed dynamically tunable switching scheme is robust against atomic dissipation associated with the help of atom-cavity coupling mismatch. Such single-photon device can be used as an elementary unit for various quantum information processing.","PeriodicalId":16826,"journal":{"name":"Journal of Physics B: Atomic, Molecular and Optical Physics","volume":"15 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140316090","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}

引用次数: 0

Vector gap solitons of spin-orbit-coupled Bose-Einstein condensate in square optical lattice 方形光晶格中自旋轨道耦合玻色-爱因斯坦凝聚态的矢量间隙孤子

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-03-12 DOI: 10.1088/1361-6455/ad2e2c

Qingqing Wang, Pu Tu, Jinping Ma, Kaihua Shao, Xi Zhao, Baolong Xi, Yan Song, Yuren Shi

引用次数: 0

Convolutional neural network for retrieval of the time-dependent bond length in a molecule from photoelectron momentum distributions 从光电子动量分布检索分子中随时间变化的键长的卷积神经网络

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-03-06 DOI: 10.1088/1361-6455/ad2e30

N I Shvetsov-Shilovski, M Lein

引用次数: 0

Targeted optimization in small-scale atomic structure calculations: application to Au I 小尺度原子结构计算中的目标优化：金 I 的应用

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-03-04 DOI: 10.1088/1361-6455/ad2b71

Sema Caliskan, Jon Grumer, Anish M Amarsi

{"title":"Targeted optimization in small-scale atomic structure calculations: application to Au I","authors":"Sema Caliskan, Jon Grumer, Anish M Amarsi","doi":"10.1088/1361-6455/ad2b71","DOIUrl":"https://doi.org/10.1088/1361-6455/ad2b71","url":null,"abstract":"The lack of reliable atomic data can be a severe limitation in astrophysical modelling, in particular of events such as kilonovae that require information on all neutron-capture elements across a wide range of ionization stages. Notably, the presence of non-orthonormalities between electron orbitals representing configurations that are close in energy can introduce significant inaccuracies in computed energies and transition probabilities. Here, we propose an explicit targeted optimization (TO) method that can effectively circumvent this concern while retaining an orthonormal orbital basis set. We illustrate this method within the framework of small-scale atomic structure models of Au I, using the <sc>Grasp2018</sc> multiconfigurational Dirac–Hartree–Fock atomic structure code. By comparing to conventional optimization schemes we show how a TO approach improves the energy level positioning and ordering. TO also leads to better agreement with experimental data for the strongest E1 transitions. This illustrates how small-scale models can be significantly improved with minor computational costs if orbital non-orthonormalities are considered carefully. These results should prove useful to multi-element atomic structure calculations in, for example, astrophysical opacity applications involving neutron-capture elements.","PeriodicalId":16826,"journal":{"name":"Journal of Physics B: Atomic, Molecular and Optical Physics","volume":"216 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140316232","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}

引用次数: 0