1
|
Filinov AV, Ara J, Tkachenko IM. Dynamic properties and the roton mode attenuation in liquid 3He: ab initio study within the self-consistent method of moments. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2023; 381:20220324. [PMID: 37393939 DOI: 10.1098/rsta.2022.0324] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 02/25/2023] [Indexed: 07/04/2023]
Abstract
The dynamic structure factor and the eigenmodes of density fluctuations in liquid 3He are studied using a novel non-perturbative approach. This new version of the self-consistent method of moments invokes up to nine sum rules and other exact relations, the two-parameter Shannon information entropy maximization procedure, and the ab initio path integral Monte Carlo simulations which provide necessary reliable input information on the system static properties. Detailed analysis is performed of the collective excitations dispersion relations, the modes' decrements and the static structure factor of 3He at the saturated vapour pressure. The results are compared to available experimental data by Albergamo et al. (Albergamo et al. 2007 Phys. Rev. Lett. 99, 205301. (doi:10.1103/PhysRevLett.99.205301)) and Fåk et al. (Fåk et al. 1994 J. Low Temp. Phys. 97, 445-487. (doi:10.1007/BF00754303)). The theory reveals a clear signature of the roton-like feature in the particle-hole segment of the excitation spectrum with a significant reduction of the roton decrement in the wavenumber range [Formula: see text]. The observed roton mode remains a well-defined collective mode even in the particle-hole band, where it is strongly damped. The existence of the roton-like mode in the bulk liquid 3He is confirmed like in other quantum fluids. The phonon branch of the spectrum is in a reasonable agreement with the same experimental data. This article is part of the theme issue 'Dynamic and transient processes in warm dense matter'.
Collapse
Affiliation(s)
- A V Filinov
- Institut für Theoretische Physik und Astrophysik, Christian-Albrechts-Universität zu Kiel, Kiel, Germany
| | - J Ara
- Instituto de Tecnología Química, Universitat Politècnica de València, Valencia, Spain
| | - I M Tkachenko
- Departament de Matemàtica Aplicada, Universitat Poliècnica de València, Valencia, Spain
- Al-Farabi Kazakh National University, Almaty, Kazakhstan
| |
Collapse
|
2
|
Arkhipov YV, Ashikbayeva A, Askaruly A, Davletov AE, Dubovtsev DY, Santybayev KS, Syzganbayeva SA, Conde L, Tkachenko IM. Dynamic characteristics of three-dimensional strongly coupled plasmas. Phys Rev E 2020; 102:053215. [PMID: 33327172 DOI: 10.1103/physreve.102.053215] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 10/26/2020] [Indexed: 11/07/2022]
Abstract
The dynamic structure factor and other dynamic characteristics of strongly coupled one-component plasmas have been studied [Yu. V. Arkhipov et al., Phys. Rev. Lett. 119, 045001 (2017)PRLTAO0031-900710.1103/PhysRevLett.119.045001] using the self-consistent version of the method of moments. Within any version of the latter, the system dielectric function satisfies all involved sum rules and other exact relations automatically, and the advantage of this version is that, in addition, the dynamic characteristics (the dynamic structure factor, the dispersion, and decay parameters of the collective modes) are all expressed in terms of the static ones (the static structure factor) without any adjustment to the simulation data. The approach outlined in the aforementioned Letter is justified in detail and applied mainly to the classical Coulomb systems achieving satisfactory agreement with new numerical simulation data. It is shown how the realm of applicability of the method can be extended to partly degenerate and multicomponent systems, even to simple liquids. Some additional theoretical results are presented in the Supplemental Material.
Collapse
Affiliation(s)
- Yu V Arkhipov
- Department of Physics and Technology, IETP, Al-Farabi Kazakh National University, al-Farabi 71, 050040 Almaty, Kazakhstan
| | - A Ashikbayeva
- Department of Physics and Technology, IETP, Al-Farabi Kazakh National University, al-Farabi 71, 050040 Almaty, Kazakhstan
| | - A Askaruly
- Department of Physics and Technology, IETP, Al-Farabi Kazakh National University, al-Farabi 71, 050040 Almaty, Kazakhstan
| | - A E Davletov
- Department of Physics and Technology, IETP, Al-Farabi Kazakh National University, al-Farabi 71, 050040 Almaty, Kazakhstan
| | - D Yu Dubovtsev
- Department of Physics and Technology, IETP, Al-Farabi Kazakh National University, al-Farabi 71, 050040 Almaty, Kazakhstan
| | - Kh S Santybayev
- Department of Physics and Technology, IETP, Al-Farabi Kazakh National University, al-Farabi 71, 050040 Almaty, Kazakhstan
| | - S A Syzganbayeva
- Department of Physics and Technology, IETP, Al-Farabi Kazakh National University, al-Farabi 71, 050040 Almaty, Kazakhstan
| | - L Conde
- Departamento de Física Aplicada a la Ingeniería Aeronáutica, ETSIAE, Universidad Politécnica de Madrid, Plaza del Cardenal Cisneros 3, 28040 Madrid, Spain
| | - I M Tkachenko
- Departament de Matemàtica Aplicada, Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
| |
Collapse
|
3
|
Arkhipov YV, Ashikbayeva AB, Askaruly A, Davletov AE, Tkachenko IM. Dielectric function of dense plasmas, their stopping power, and sum rules. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:053102. [PMID: 25493892 DOI: 10.1103/physreve.90.053102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Indexed: 06/04/2023]
Abstract
Mathematical, particularly, asymptotic properties of the random-phase approximation, Mermin approximation, and extended Mermin-type approximation of the coupled plasma dielectric function are analyzed within the method of moments. These models are generalized for two-component plasmas. Some drawbacks and advantages of the above models are pointed out. The two-component plasma stopping power is shown to be enhanced with respect to that of the electron fluid.
Collapse
Affiliation(s)
- Yu V Arkhipov
- Department of Physics and Technology, IETP, al-Farabi Kazakh National University, al-Farabi 71, 050040 Almaty, Kazakhstan
| | - A B Ashikbayeva
- Department of Physics and Technology, IETP, al-Farabi Kazakh National University, al-Farabi 71, 050040 Almaty, Kazakhstan
| | - A Askaruly
- Department of Physics and Technology, IETP, al-Farabi Kazakh National University, al-Farabi 71, 050040 Almaty, Kazakhstan
| | - A E Davletov
- Department of Physics and Technology, IETP, al-Farabi Kazakh National University, al-Farabi 71, 050040 Almaty, Kazakhstan
| | - I M Tkachenko
- Instituto de Matemática Pura y Aplicada, Universidad Politécnica de Valencia, Camino de Vera s/n, 46022 Valencia, Spain
| |
Collapse
|