2017 Fiscal Year Annual Research Report
Controlling vortex rings in Bose--Einstein condensates
Project/Area Number |
17J01488
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Research Institution | Okinawa Institute of Science and Technology Graduate University |
Principal Investigator |
SCHLOSS James Ryan 沖縄科学技術大学院大学, 科学技術研究科, 特別研究員(DC1)
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Project Period (FY) |
2017-04-26 – 2020-03-31
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Keywords | Computing / BEC / Turbulence / Quantum Systems / Vortex Dynamics |
Outline of Annual Research Achievements |
For the 2017 fiscal year, I have developed a robust GPU codebase, GPUE, to solve the Gross-Pitaevskii equation in 3D and determine what types of vortex structures and dynamics can be found when coupling the light from an optical nanofiber to a toroidally trapped Bose--Einstein Condensate (BEC). With this system, we confirmed that it was possible to create and control vortex rings and have also shown that by using linearly-polarized light and higher-order modes, we can create more complex vortex structures. This is the first experimentally realistic system that can provide this level of control over vortex structures and dynamics and will allow researchers to create a stable vortex state to study vortex turbulence and other, more complicated applications of quantum turbulence. These results are currently being written into a paper to be submitted to the Physics of Fluids journal.
In addition, the codebase has been sufficiently developed for a broad range of applications and can be used for any arbitrary single-component BEC system. It has been benchmarked and consistently out-performs other codebases. For this reason, we are also submitting the code to the Journal of Open Source Software and will be continuing to develop it further for our own applications and applications of other researchers around the world. For example, we have used the GPUE codebase to study quantum turbulence in 2D BEC systems for a low and high number of vortices.
Overall, the progress in the 2017 fiscal year adequately set the foundation for future work and will be published soon.
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Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
In this year, research progressed as expected. As mentioned in the summary, we have explored the capabilities of this system to create and control vortex rings and other, more complicated vortex structures. In doing this, we have also developed a robust codebase to perform our calculations and this codebase is currently being used in a number of different applications related to vortex turbulence and vortex dynamics. The results are currently being written into a publication to be submitted to Physics of Fluids and the code will be submitted to the Journal of Open Source Software. We have also further explored the physical system and determined the limit of the vortex structures that can be created by coupling the evanescent field of an optical nanofiber to a toroidally trapped BEC. This progress is precisely what we expected; however, we expected the publications, themselves, to be published in the 2017 fiscal year. Instead, they will be published early in the 2018 fiscal year. Because of this, we used the funds from 2017 to purchase the computing equipment we were expecting to purchase in 2018 and will shift the publication funds to 2018. This is ultimately a small change to the research plan and will not change the timeline significantly.
These results have adequately laid the foundation for future research and will certainly be used in 2018 and beyond. In addition, we will develop the codebase to simulate a larger number of systems so more researchers can use it around the world. The intent is to create a stable codebase for general use for similar situations.
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Strategy for Future Research Activity |
Because the research done in 2017 was precisely what we expected, we intend to continue along the path paved by our initial proposal. As described previously, 2018 will be used primarily to develop the scientific software necessary for future applications. We will first publish the code and initial results and then continue developing the codebase and polishing the numerical techniques by trying different numerical methods never before attempted on massively parallel, psuedo-spectral GPU code. The algorithms we develop will hopefully allow researchers of several different areas to increase the performance of any codebase that uses spectral or pseudo-spectral methods. In addition, we have begun development of a novel vortex-tracking method that will be completed soon. This should help researchers studying quantum turbulence and will hopefully be used for a wide array of physical simulations.
We will also attempt to continue developing experimentally realistic techniques to create and control more complicated vortex structures, which may involve studying other systems beyond the optical nanofiber system we have been using until this point. Afterward, we will study the evolution of vortices and determine which structures are topologically possible. Ideally, this research will pave the way for the future of research in quantum turbulence, and should also create new algorithms and methods with a much broader application.
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Research Products
(1 results)