Journal of Physics B: Atomic, Molecular and Optical Physics最新文献_第3页

Simulation of deflection and photon emission of ultra-relativistic electrons and positrons in a quasi-mosaic bent silicon crystal 模拟准马赛克弯曲硅晶体中超相对论电子和正电子的偏转与光子发射

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-08-13 DOI: 10.1088/1361-6455/ad6b65

Paulo E Ibañez-Almaguer, Germán Rojas-Lorenzo, Maykel Márquez-Mijares, Jesús Rubayo-Soneira, Gennady B Sushko, Andrei V Korol, Andrey V Solov’yov

{"title":"Simulation of deflection and photon emission of ultra-relativistic electrons and positrons in a quasi-mosaic bent silicon crystal","authors":"Paulo E Ibañez-Almaguer, Germán Rojas-Lorenzo, Maykel Márquez-Mijares, Jesús Rubayo-Soneira, Gennady B Sushko, Andrei V Korol, Andrey V Solov’yov","doi":"10.1088/1361-6455/ad6b65","DOIUrl":"https://doi.org/10.1088/1361-6455/ad6b65","url":null,"abstract":"A comprehensive numerical investigation has been conducted on the angular distribution and spectrum of radiation emitted by 855 MeV electron and positron beams while traversing a ‘quasi-mosaic’ bent silicon (111) crystal. This interaction of charged particles with a bent crystal gives rise to various phenomena such as channeling, dechanneling, volume reflection, and volume capture. The crystal’s geometry, emittance of the collimated particle beams, as well as their alignment with respect to the crystal, have been taken into account as they are essential for an accurate quantitative description of the processes. The simulations have been performed using a specialized relativistic molecular dynamics module implemented in the MBN Explorer package. The angular distribution of the particles after traversing the crystal has been calculated for beams of different emittances as well as for different anticlastic curvatures of the bent crystals. For the electron beam, the angular distributions of the deflected particles and the spectrum of radiation obtained in the simulations are compared with the experimental data collected at the Mainz Microtron facility. For the positron beam such calculations have been performed for the first time. We predict significant differences in the angular distributions and the radiation spectra for positrons versus electrons.","PeriodicalId":16826,"journal":{"name":"Journal of Physics B: Atomic, Molecular and Optical Physics","volume":"3 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142190843","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}

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A comparative study of transition oscillator strengths and static polarizabilities of the hydrogen atom confined in Gaussian potential 限制在高斯势中的氢原子的过渡振荡器强度和静态极化率的比较研究

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-08-13 DOI: 10.1088/1361-6455/ad6b66

Junbo Liu, Xiangjun Lai, Xiao Hu Ji, Aihua Liu, Henry E Montgomery Jr, Yew Kam Ho, Li Guang Jiao

{"title":"A comparative study of transition oscillator strengths and static polarizabilities of the hydrogen atom confined in Gaussian potential","authors":"Junbo Liu, Xiangjun Lai, Xiao Hu Ji, Aihua Liu, Henry E Montgomery Jr, Yew Kam Ho, Li Guang Jiao","doi":"10.1088/1361-6455/ad6b66","DOIUrl":"https://doi.org/10.1088/1361-6455/ad6b66","url":null,"abstract":"The multipole (dipole, quadrupole, and octopole) photon-absorption transition oscillator strengths for the ground state of hydrogen atom confined in Gaussian potential are investigated for a great variety of potential depths and confining radii. It is interestingly found that at fixed potential depth the gradual increase of confining radius shows first destructive and then constructive effect on the multipole oscillator strengths. Such an effect can be understood from the overlap between the initial and final states. Multipole polarizabilities of the system are obtained through the sum-over-states formalism where the contributions from both the bound and continuum spectra of the system are included. Although the separate bound and continuum contributions can not be determined accurately, due to the long-range nature of the Coulomb potential introduced by the nucleus, their summations can be obtained to reasonably good accuracy, leading to fast convergence of numerical calculations of multipole polarizabilities. The present results are compared with previous calculations available in the literature. Although good agreement is observed for the dipole polarizability, significant differences exist in the quadrupole polarizability and orders-of-magnitude differences appear in the octopole polarizability. The possible reason for such large differences is analyzed by comparing the sum rule of corresponding oscillator strengths.","PeriodicalId":16826,"journal":{"name":"Journal of Physics B: Atomic, Molecular and Optical Physics","volume":"78 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142190848","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

Perspective: towards real-time extreme ultraviolet to x-ray imaging and spectroscopy of laser-driven materials 视角：实现激光驱动材料的实时极紫外至 X 射线成像和光谱分析

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-08-13 DOI: 10.1088/1361-6455/ad5fd4

Daria Popova-Gorelova

引用次数: 0

Indirect measurement of atomic magneto-optical rotation via Hilbert transform 通过希尔伯特变换间接测量原子磁光旋转

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-08-06 DOI: 10.1088/1361-6455/ad5e24

Jack D Briscoe, Danielle Pizzey, Steven A Wrathmall and Ifan G Hughes

{"title":"Indirect measurement of atomic magneto-optical rotation via Hilbert transform","authors":"Jack D Briscoe, Danielle Pizzey, Steven A Wrathmall and Ifan G Hughes","doi":"10.1088/1361-6455/ad5e24","DOIUrl":"https://doi.org/10.1088/1361-6455/ad5e24","url":null,"abstract":"The Kramers–Kronig relations are a pivotal foundation of linear optics and atomic physics, embedding a physical connection between the real and imaginary components of any causal response function. A mathematically equivalent, but simpler, approach instead utilises the Hilbert transform. In a previous study, the Hilbert transform was applied to absorption spectra in order to infer the sole refractive index of an atomic medium in the absence of an external magnetic field. The presence of a magnetic field causes the medium to become birefringent and dichroic, and therefore it is instead characterised by two refractive indices. In this study, we apply the same Hilbert transform technique to independently measure both refractive indices of a birefringent atomic medium, leading to an indirect measurement of atomic magneto-optical rotation. Key to this measurement is the insight that inputting specific light polarisations into an atomic medium induces absorption associated with only one of the refractive indices. We show this is true in two configurations, commonly referred to in literature as the Faraday and Voigt geometries, which differ by the magnetic field orientation with respect to the light wavevector. For both cases, we measure the two refractive indices independently for a Rb thermal vapour in a magnetic field, finding excellent agreement with theory. This study further emphasises the application of the Hilbert transform to the field of quantum and atomic optics in the linear regime.","PeriodicalId":16826,"journal":{"name":"Journal of Physics B: Atomic, Molecular and Optical Physics","volume":"46 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141937009","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

Doppler sensitivity and resonant tuning of Rydberg atom-based antennas 基于雷德贝格原子的天线的多普勒灵敏度和谐振调谐

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-07-24 DOI: 10.1088/1361-6455/ad6385

Peter B Weichman

{"title":"Doppler sensitivity and resonant tuning of Rydberg atom-based antennas","authors":"Peter B Weichman","doi":"10.1088/1361-6455/ad6385","DOIUrl":"https://doi.org/10.1088/1361-6455/ad6385","url":null,"abstract":"Radio frequency antennas based on Rydberg atom vapor cells can in principle reach sensitivities beyond those of any conventional wire antenna, especially at lower frequencies where very long wires are needed to accommodate the increasing wavelength. They also have other desirable features such as consisting of nonmetallic, hence lower profile, elements. This paper presents a detailed theoretical investigation of Rydberg antenna sensitivity, elucidating parameter regimes that could cumulatively lead to a sensitivity increase 2–3 orders of magnitude beyond that of currently tested configurations. The key insight is to optimally combine the advantages of two well-studied approaches: (i) three laser ‘2D star configuration’ setups that, when enhanced with increased laser power, to some degree compensate for atom motion-induced Doppler broadening, and (ii) resonant coupling between a pair of near-degenerate Rydberg levels, tuned via a local oscillator to the incident signal of interest. The advantage of the star setup is subtle because it only restores the overall sensitivity to the expected Doppler-limited value, compensating for additional significant off-resonance reductions where differently moving atom sub-populations destructively interfere with each other in the net signal. An additional unique advantage of local oscillator tuning is that it leads to vastly narrower line widths, as low as ∼10 kHz set by the intrinsic Rydberg state lifetimes, rather than the typical ∼10 MHz scale set by the core state lifetimes. Intuitively, with this setup the two Rydberg states may be tuned to act as an independent high-q cavity, a point of view supported by a study of the frequency-dependence of the antenna resonant response. There are a number of practical experimental advances, especially larger ∼1 cm laser beam widths, required to suppress various extrinsic line broadening effects and to fully exploit this ‘Rydberg superheterodyne’ response.","PeriodicalId":16826,"journal":{"name":"Journal of Physics B: Atomic, Molecular and Optical Physics","volume":"2 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141782045","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

Dissociative recombination of NS+ in collision with slow electrons NS+ 与慢速电子碰撞时的分解重组

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-07-17 DOI: 10.1088/1361-6455/ad5e20

R Hassaine, F Gauchet, F Iacob, J Zs Mezei, E Roueff, J Tennyson and I F Schneider

引用次数: 0

Exploring the origin of stronger survival of polarized vortex beams through scattering media 探索极化涡流束在散射介质中生存能力更强的原因

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-07-11 DOI: 10.1088/1361-6455/ad5e22

Atharva Paranjape, Shyamal Guchhait, Athira B S and Nirmalya Ghosh

{"title":"Exploring the origin of stronger survival of polarized vortex beams through scattering media","authors":"Atharva Paranjape, Shyamal Guchhait, Athira B S and Nirmalya Ghosh","doi":"10.1088/1361-6455/ad5e22","DOIUrl":"https://doi.org/10.1088/1361-6455/ad5e22","url":null,"abstract":"Laguerre–Gaussian (LG) beams carrying orbital angular momentum (OAM) have shown promise in deep tissue imaging, medical diagnostics, and optical communication due to their robust propagation properties through scattering media. The insight on the mechanism for stronger survival of OAM carrying beam in tissue-like turbid media is expected to contribute towards a better understanding of light transport in the presence of scattering, as well as guide optimization of the intensity, phase, and polarization structure of light for use in biomedical applications like in tissue imaging. We examine the scattering properties by studying the propagation of polarized vortex beams transmitted through tissue-like turbid scattering media. We demonstrate that the intensity profile has a much more profound effect on depolarization than the phase profile for LG beams. Our results indicate that the observed stronger propagation for the higher-order LG beams is due to a higher anisotropy factor g, as seen by the incident beam. We have performed the degree of polarization measurements for the forward scattered light in the case of both LG beams and perfect vortex beams with varying topological charges. A comparison between the observed depolarization trends for the two classes of OAM-carrying beams suggests that the robust scattering properties of the LG beams originate from the intensity profile while the phase profile does not seem to play a major role in the stronger survival of OAM-carrying beam in turbid media.","PeriodicalId":16826,"journal":{"name":"Journal of Physics B: Atomic, Molecular and Optical Physics","volume":"31 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141608489","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

The electron affinity of rubidium: a state selective measurement 铷的电子亲和力：状态选择性测量

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-07-11 DOI: 10.1088/1361-6455/ad5e25

Annie Ringvall-Moberg, Miranda Nichols, José E Navarro Navarrete, Uldis Bērziņš, Viola C D’mello, Julia Karls, Di Lu, Yazareth Peña Rodríguez, Rachel Poulose, Andrea Morales Rodríguez, Keerthana Ravi, Meera Ramachandran, Vitali Zhaunerchyk, Dag Hanstorp and David Leimbach

{"title":"The electron affinity of rubidium: a state selective measurement","authors":"Annie Ringvall-Moberg, Miranda Nichols, José E Navarro Navarrete, Uldis Bērziņš, Viola C D’mello, Julia Karls, Di Lu, Yazareth Peña Rodríguez, Rachel Poulose, Andrea Morales Rodríguez, Keerthana Ravi, Meera Ramachandran, Vitali Zhaunerchyk, Dag Hanstorp and David Leimbach","doi":"10.1088/1361-6455/ad5e25","DOIUrl":"https://doi.org/10.1088/1361-6455/ad5e25","url":null,"abstract":"Negative ions, which are formed when an electron is attached to a neutral system, are unique quantum systems. The lack of a long-range Coulomb force causes the inter-electronic interactions to become relatively more important. As a consequence, the independent particle model, which adequately describes atomic structure under normal conditions, breaks down. The alkali negative ions, with a closed valence s-shell, are among the simplest anionic systems. Hence, they can favorably be used to benchmark atomic theory. In this work, we have determined the electron affinity of 85Rb by measuring the relative partial photodetachment cross section of the negative ion, leaving the residual atom in the 5p excited state. Resonance ionization spectroscopy allows for state selectivity and the ability to measure the Wigner s-wave threshold onset of the photodetachment process. The electron affinity of 85Rb was determined to be 485.887(6) meV.","PeriodicalId":16826,"journal":{"name":"Journal of Physics B: Atomic, Molecular and Optical Physics","volume":"20 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141608491","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

Evolution of level population in Ar interacting with XFEL pulses: impact of resonant absorptions 与 XFEL 脉冲相互作用的氩气中电平群的演变：共振吸收的影响

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-07-10 DOI: 10.1088/1361-6455/ad5ee5

Jie Yan, Guanpeng Yan, Fengtao Jin, Yongjun Li, Cheng Gao, Jiaolong Zeng and Jianmin Yuan

{"title":"Evolution of level population in Ar interacting with XFEL pulses: impact of resonant absorptions","authors":"Jie Yan, Guanpeng Yan, Fengtao Jin, Yongjun Li, Cheng Gao, Jiaolong Zeng and Jianmin Yuan","doi":"10.1088/1361-6455/ad5ee5","DOIUrl":"https://doi.org/10.1088/1361-6455/ad5ee5","url":null,"abstract":"Theoretical exploration of the population dynamics at fine-structure levels of Ar atoms interacting with ultrafast ultraintense x-ray free electron laser (XFEL) pulses is conducted. A time-dependent rate equation based on a detailed-level accounting approach is applied for tracking population levels, encompassing microscopic atomic processes such as photoexcitation, radiative decay, photoionization and Auger decay. A Monte Carlo algorithm is implemented to solve large-scale rate equations efficiently. The primary investigation centers on generating Ar17+ through resonant absorption by the second-harmonic radiation of the x-ray pulse. The calculated population ratios of Ar17+ to Ar16+ align well with the experimental measurements (LaForge et al 2021 Phys. Rev. Lett.127 213202). In comparison to the transition energy of the strongest line, of Ar16+, there is a distinct ∼25 eV red shift in the peak ratio, which is attributed to the presence of intricate resonant channels in the lower ionization stages. The results demonstrate the sensitivity of the population ratio Ar17+/Ar16+ to the laser pulse parameters such as x-ray pulse duration, bandwidth and the contribution of second-harmonic radiation, indicating their potential as diagnostic tools in future experiments.","PeriodicalId":16826,"journal":{"name":"Journal of Physics B: Atomic, Molecular and Optical Physics","volume":"21 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141585122","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

Influence of orbital angular momentum of light on random spin-split modes in disordered anisotropic optical media 光的轨道角动量对无序各向异性光学介质中随机自旋分裂模式的影响

IF 1.6 4区物理与天体物理

Journal of Physics B: Atomic, Molecular and Optical Physics Pub Date : 2024-07-09 DOI: 10.1088/1361-6455/ad5e21

Anwesha Panda, Sneha Dey, Yogishree Arabinda Panda, Aditya Anurag Dash, Aloke Jana and Nirmalya Ghosh

{"title":"Influence of orbital angular momentum of light on random spin-split modes in disordered anisotropic optical media","authors":"Anwesha Panda, Sneha Dey, Yogishree Arabinda Panda, Aditya Anurag Dash, Aloke Jana and Nirmalya Ghosh","doi":"10.1088/1361-6455/ad5e21","DOIUrl":"https://doi.org/10.1088/1361-6455/ad5e21","url":null,"abstract":"Spin–orbit interaction of light in a disordered anisotropic medium is known to yield spin split modes in the momentum domain because of the random spatial gradient of the geometric phase of light. Here, we have studied the statistics of such spin-split modes for beams carrying intrinsic orbital angular momentum through the quantification of momentum domain entropy and investigated its dependence on various beam parameters. The influence of the spatial structure of the beam and the phase vortex on the statistics of the spin split modes were separately investigated using input Laguerre–Gaussian and Perfect Vortex beams passing through a disordered anisotropic medium with controlled input disorder parameter, which was realized by modulating the pixels of a liquid crystal-based spatial light modulator. The results of systematic investigations on the impact of beam waist, spot size and topological charge of the vortex beam show that the influence of the spot size on the emergence of the random spin split modes is much more significant as compared to the other beam parameters.","PeriodicalId":16826,"journal":{"name":"Journal of Physics B: Atomic, Molecular and Optical Physics","volume":"7 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141570056","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