Journal of Physics B最新文献

{"title":"Partial Identification of visible lines from W24+ ions in an electron-beam ion trap","authors":"Bingli Li, Fanhu Qu, Ning Fu, Yiming Xie, Xin Liu, Yang Yang, Baoren Wei, Yaming Zou, Jun Xiao","doi":"10.1088/1361-6455/acfbce","DOIUrl":"https://doi.org/10.1088/1361-6455/acfbce","url":null,"abstract":"Abstract To better understand the structure of the open <?CDATA $4{text{f}}$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:mn>4</mml:mn> <mml:mrow> <mml:mtext>f</mml:mtext> </mml:mrow> </mml:math> shell, the spectroscopic data in the 420–600 nm range of the highly charged ions of W 24+ obtained with an electron beam ion trap are presented. Detailed collisional-radiative (CR) modeling has been used to simulate the spectrum. The atomic structure data for the CR modeling were calculated using the relativistic many-body perturbation theory (RMBPT) and the large-scale relativistic configuration interaction (RCI) method implemented in the flexible atomic code. The two set theoretical calculation wavelengths for six observed lines are in reasonable agreement with the experimental observations, with average deviations of 0.61% for RMBPT and 1.75% for RCI. The relative intensities of the identified lines have also been investigated, revealing a strong correlation to electron density from <?CDATA ${n_e}$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:mrow> <mml:msub> <mml:mi>n</mml:mi> <mml:mi>e</mml:mi> </mml:msub> </mml:mrow> </mml:math> = 10 9 to 10 11 cm −3 .","PeriodicalId":16799,"journal":{"name":"Journal of Physics B","volume":"17 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135823141","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}

{"title":"Winding real and order-parameter spaces via lump solitons of spinor BEC on sphere","authors":"Yan He, Chih-Chun Chien","doi":"10.1088/1361-6455/ad013b","DOIUrl":"https://doi.org/10.1088/1361-6455/ad013b","url":null,"abstract":"Abstract The three condensate wavefunctions of a F = 1 spinor Bose–Einstein condensate on a spherical shell can map the real space to the order-parameter space that also has a spherical geometry, giving rise to topological excitations called lump solitons. The homotopy of the mapping endows the lump solitons with quantized winding numbers counting the wrapping between the two spaces. We present several lump-soliton solutions to the nonlinear coupled equations minimizing the energy functional. The energies of the lump solitons with different winding numbers indicate coexistence of lumps with different winding numbers and a lack of advantage to break a higher-winding lump soliton into multiple lower-winding ones. Possible implications are discussed since the predictions are testable in cold-atom experiments.","PeriodicalId":16799,"journal":{"name":"Journal of Physics B","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135823175","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}

{"title":"Simultaneous observation of noble gases and highly charged ions in an electron beam ion trap for accurate wavelength calibration of optical transitions","authors":"Naoki Kimura, Nobuyuki Nakamura","doi":"10.1088/1361-6455/ad0400","DOIUrl":"https://doi.org/10.1088/1361-6455/ad0400","url":null,"abstract":"Abstract Spectral lines of buffer noble gases injected into an electron beam ion trap have recently been used as a reference to aid accurate determination of the wavelengths of optical transitions of highly charged ions. Simultaneous observation of emission lines of highly charged ions along with those of neutral atoms or singly charged ions represents a reliable method for wavelength calibration that suppresses systematic uncertainties. Here, we present visible and infrared emission spectra of buffer Ne and Ar gases in an electron beam ion trap and briefly review the buffer gas calibration method. The experimental conditions required for implementing the calibration method are discussed by investigating the dependence of the emission spectra of mixtures of highly charged ions and noble gases on electron beam’s parameters and gas pressure.","PeriodicalId":16799,"journal":{"name":"Journal of Physics B","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135944204","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}

{"title":"Absorption of hybrid fibre modes by Cs atoms inquadrupole transitions","authors":"Smail Bougouffa, Mohamed Babiker","doi":"10.1088/1361-6455/acfd71","DOIUrl":"https://doi.org/10.1088/1361-6455/acfd71","url":null,"abstract":"Abstract We evaluate the rate of the absorption of an optical nanofibre mode by a Cs atom in an electric quadrupole transition. With the Cs atom localised near the outer surface of the optical nano-fibre, an interaction occurs between the atomic quadrupole tensor components and the gradients of the vector components of the electric field of a hybrid fibre mode. The absorption rate is evaluated as a function of the radial position of the atom from the fibre axis, assuming a specific value of the laser power and we use experimentally accessible parameters. We find that the absorption of the hybrid modes by the Cs atom decreases as the atom recedes away from the fibre axis and it formally vanishes at sufficiently large radial distances. Close to the fibre, however, the absorption rate for the input power chosen can be two orders of magnitude larger than the quadrupole de-excitation rate despite the moderate power used.","PeriodicalId":16799,"journal":{"name":"Journal of Physics B","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135945118","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}

{"title":"Bogoliubov spectrum and the dynamic structure factor in a quasi-two-dimensional spin-orbit coupled BEC","authors":"Inderpreet Kaur, Sankalpa Ghosh","doi":"10.1088/1361-6455/acfd70","DOIUrl":"https://doi.org/10.1088/1361-6455/acfd70","url":null,"abstract":"Abstract We compute the Bogoliubov–de Gennes excitation spectrum in a trapped two-component spin-orbit-coupled (SOC) Bose–Einstein condensate (BEC) in quasi-two-dimensions as a function of linear and angular momentum and analyze them. The excitation spectrum exhibits a minima-like feature at finite momentum for the immiscible SOC-BEC configuration, which implies dynamical instability. We augment these results by computing the dynamic structure factor in the density and pseudo-spin sector, and discuss its interesting features that can be experimentally measured through Bragg spectroscopy of such ultracold condensates.","PeriodicalId":16799,"journal":{"name":"Journal of Physics B","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135923431","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}

{"title":"Hyperfine transition induced by atomic motion above a paraffin-coated magnetic film","authors":"Naota Sekiguchi, Hiroaki Usui, Atsushi Hatakeyama","doi":"10.1088/1361-6455/acfde5","DOIUrl":"https://doi.org/10.1088/1361-6455/acfde5","url":null,"abstract":"Abstract We measured transitions between the hyperfine levels of the electronic ground state of potassium-39 atoms (transition frequency: 460 MHz) as the atoms moved through a periodic magneto-static field produced above the magnetic-stripe domains of a magnetic film. The period length of the magnetic field was 3.8 µ m. The atoms were incident to the field as an impinging beam with the most probable velocity of 550 m s −1 and experienced a peak oscillating field of 20 mT. Unwanted spin relaxation caused by the collisions of the atoms with the film surface was suppressed by the paraffin coating on the film. We observed increasing hyperfine transition probabilities as the frequency of the field oscillations experienced by the atoms increased from 0 to 140 MHz for the atomic velocity of 550 m s −1 , by changing the incident angle of the atomic beam with respect to the stripe domains. Numerical calculation of the time evolution of the hyperfine states revealed that the oscillating magnetic field experienced by the atoms induced the hyperfine transitions, and the main process was not a single-quantum transition but rather multi-quanta transitions.","PeriodicalId":16799,"journal":{"name":"Journal of Physics B","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136254310","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}

{"title":"Non-ideal classical plasma: laser pulse effects and dynamic dipole polarizabilities","authors":"Shalini Lumb Talwar, Sonia Lumb, Kalidas Sen, Vinod Prasad","doi":"10.1088/1361-6455/ad018d","DOIUrl":"https://doi.org/10.1088/1361-6455/ad018d","url":null,"abstract":"Abstract The properties of a hydrogen atom inside a non-ideal classical plasma, in terms of its behaviour in the presence of an applied laser pulse, are explored. The strength of the pulse is chosen such that it mantains near sphericity of the system. The pulse parameters have a strong bearing on the final state attained by the system after its interaction with the pulse. Dynamic dipole polarizability is calculated and the poles are observed to be red shifted with increase in non-ideality as well as increase in temperature of plasma. These polarizabilities for frequencies of the field below the frequency corresponding to the first pole are found to be greater for larger values of field frequencies, plasma non-ideality and electron plasma temperatures.","PeriodicalId":16799,"journal":{"name":"Journal of Physics B","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135044605","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}

{"title":"Numerical modeling of the multi-stage Stern–Gerlach experiment by Frisch and Segrè using co-quantum dynamics via the Bloch equation","authors":"Kelvin Titimbo, David C Garrett, S Süleyman Kahraman, Zhe He, Lihong V Wang","doi":"10.1088/1361-6455/acf971","DOIUrl":"https://doi.org/10.1088/1361-6455/acf971","url":null,"abstract":"Abstract We numerically study the spin flip in the Frisch–Segrè experiment, the first multi-stage Stern–Gerlach experiment, within the context of the novel co-quantum dynamics (CQD) theory. We model the middle stage responsible for spin rotation by sampling the atoms with the Monte Carlo method and solving the dynamics of the electron and nuclear magnetic moments numerically according to the Bloch equation. The simulation shows that CQD closely reproduces, without using any fitting parameters, the experimental observations reported by Frisch and Segrè in 1933, which have so far lacked theoretical predictions.","PeriodicalId":16799,"journal":{"name":"Journal of Physics B","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134960265","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}

{"title":"Bursts of polarised single photons from atom-cavity sources","authors":"Jan Ole Ernst, Juan-Rafael Alvarez, Thomas D Barrett, Axel Kuhn","doi":"10.1088/1361-6455/acf9d2","DOIUrl":"https://doi.org/10.1088/1361-6455/acf9d2","url":null,"abstract":"Abstract Photonic qubits play an instrumental role in the development of advanced quantum technologies, including quantum networking, boson sampling and measurement based quantum computing. A promising framework for the deterministic production of indistinguishable single photons is an atomic emitter coupled to a single mode of a high finesse optical cavity. Polarisation control is an important cornerstone, particularly when the polarisation defines the state of a quantum bit. Here, we propose a scheme for producing bursts of polarised single photons by coupling a generalised atomic emitter to an optical cavity, exploiting a particular choice of quantisation axis. In connection with two re-preparation methods, simulations predict ten-photon bursts coincidence count rates on the order of 1 kHz with single <?CDATA $^{87}mathrm{Rb}$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:msup> <mml:mi /> <mml:mrow> <mml:mn>87</mml:mn> </mml:mrow> </mml:msup> <mml:mrow> <mml:mi mathvariant=\"normal\">R</mml:mi> <mml:mi mathvariant=\"normal\">b</mml:mi> </mml:mrow> </mml:math> atoms trapped in a state of the art optical cavity. This paves the way for novel n -photon experiments with atom-cavity sources.","PeriodicalId":16799,"journal":{"name":"Journal of Physics B","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135769289","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}

{"title":"Study of the velocity-selection satellites present in the 5P_3/2 → 6P_J (J = 1/2, 3/2) electric quadrupole transitions in atomic rubidium.","authors":"Francisco Sebastian Ponciano Ojeda, Cristian Adrián Moijca-Casique, Lina M Hoyos-Campo, Fernando Ramirez-Martinez, Jesus Flores Mijangos, Jose Jimenez-Mier","doi":"10.1088/1361-6455/acf821","DOIUrl":"https://doi.org/10.1088/1361-6455/acf821","url":null,"abstract":"Abstract This article presents detailed experimental and theoretical studies of the satellite fluorescence lines observed when the <?CDATA $5P_{3/2} to 6P_J $?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:mn>5</mml:mn> <mml:msub> <mml:mi>P</mml:mi> <mml:mrow> <mml:mn>3</mml:mn> <mml:mrow> <mml:mo>/</mml:mo> </mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msub> <mml:mo stretchy=\"false\">→</mml:mo> <mml:mn>6</mml:mn> <mml:msub> <mml:mi>P</mml:mi> <mml:mi>J</mml:mi> </mml:msub> </mml:math> , ( <?CDATA $J = 1/2 $?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:mi>J</mml:mi> <mml:mo>=</mml:mo> <mml:mn>1</mml:mn> <mml:mrow> <mml:mo>/</mml:mo> </mml:mrow> <mml:mn>2</mml:mn> </mml:math> , <?CDATA $3/2$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:mn>3</mml:mn> <mml:mrow> <mml:mo>/</mml:mo> </mml:mrow> <mml:mn>2</mml:mn> </mml:math> ) electric quadrupole transition (E2) is excited in a room temperature vapor of rubidium atoms. The initial state of this E2 transition is prepared by a narrow linewidth (9 MHz) laser locked to one of the dominant <?CDATA $5S_{1/2} to 5P_{3/2} $?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:mn>5</mml:mn> <mml:msub> <mml:mi>S</mml:mi> <mml:mrow> <mml:mn>1</mml:mn> <mml:mrow> <mml:mo>/</mml:mo> </mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msub> <mml:mo stretchy=\"false\">→</mml:mo> <mml:mn>5</mml:mn> <mml:msub> <mml:mi>P</mml:mi> <mml:mrow> <mml:mn>3</mml:mn> <mml:mrow> <mml:mo>/</mml:mo> </mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msub> </mml:math> D2 hyperfine excitations for zero-velocity atoms. Effects due to the selection of different atomic velocity classes in this preparation step are responsible for the presence of several satellite lines that can be found in the fluorescence decay spectra of both 85 Rb and 87 Rb. Compared to the main lines, these satellites do not show a strong dependence on the relative linear polarization directions of the lasers used in the preparation and the electric quadrupole steps. The relative intensities of the satellites decrease as the intensity of the preparation laser increases. Results of a rate equation calculation that explicitly includes selection-of-velocity effects indicate that optical pumping plays a central role in determining the relative intensities and the polarization dependence of the satellite lines. When the preparation laser is locked to the <?CDATA $5S_{1/2} F_1 = 1 to 5P_{3/2} F_2 = 0$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:mn>5</mml:mn> <mml:msub> <mml:mi>S</mml:mi> <mml:mrow> <mml:mn>1</mml:mn> <mml:mrow> <mml:mo>/</mml:mo> </mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msub> <mml:mtext> </mml:mtext> <mml:msub> <mml:mi>F</mml:mi> <mml:mn>1</mml:mn> </mml:msub> <mml:mo>=</mml:mo> <mml:mn>1</mml:mn> <mml:mo stretchy=\"false\">→</mml:mo> <mml:mn>5</mml:mn> <mml:msub> <mml:mi>","PeriodicalId":16799,"journal":{"name":"Journal of Physics B","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136129915","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}