Development of a Platform for Modifying, Controlling, and Measuring Quantum Properties of Solid Materials Using Microwaves
Professor Jo Gil-young, POSTECH
[Asia Economy Reporter Sunmi Park] A research team led by Professors Gilho Lee and Gilyoung Cho from the Department of Physics at POSTECH, supported by the Samsung Future Technology Development Program, has succeeded in developing a platform that can control and measure the quantum properties of solid materials in various ways using light. Samsung Electronics announced on the 22nd that the related paper has been published in the top international journal 'Nature'.
In the scientific community, it has been hypothesized since the mid-1900s that for very small solid materials, in addition to conventional methods (heat, pressure, chemical additives, etc.), shining light on them can change their quantum properties to a 'Floquet state'. If Floquet research continues to yield results, it is expected that by irradiating light, 'topological materials' (next-generation quantum materials that can overcome the limitations of conventional semiconductor-based information devices) can be realized, making it highly useful in new materials and quantum technology fields, which is why related research is active worldwide.
However, until now, the realized Floquet states have lasted only for an extremely short moment on the order of 250 femtoseconds (1 femtosecond is one quadrillionth of a second). This is because the energy applied to quantum solid materials to realize the Floquet state is very large, generating strong heat.
Gilho Lee, Professor at POSTECH
Professor Gilho Lee's research team succeeded in implementing the Floquet state for a long time by gradually irradiating microwaves instead of conventional infrared light on a 'graphene-Josephson junction device.' The intensity of the light was reduced to one trillionth of the previous level, significantly reducing heat generation, and the Floquet state lasted for more than 25 hours.
Additionally, the research team succeeded in quantitatively confirming the characteristics of the Floquet state, which vary depending on the intensity and wavelength of light applied to the 'graphene-Josephson junction device,' through an optimized 'superconducting tunneling' analysis method.
Professors Gilho Lee and Gilyoung Cho said, "This research is meaningful in that it created a platform where the Floquet state can be continuously maintained, allowing detailed study of the Floquet state," and added, "We plan to conduct research to clarify the correlation between the properties of light, such as polarization, and the Floquet state in the future."
The research team’s study has been supported for five years since being selected as a project under the Samsung Future Technology Development Program in June 2017.
Meanwhile, the Samsung Future Technology Development Program received over 720 applications for this year’s open call research projects in the fields of basic science, materials, and ICT, and conducted document and presentation reviews. The final list of supported projects will be announced soon. If selected, projects can receive research funding of up to several billion won over a maximum of five years. Last year, the total research funding provided reached 95.68 billion won, including 49 open call projects with 80.47 billion won and 12 designated theme projects with 15.21 billion won.
The Samsung Future Technology Development Program is a public research support initiative launched in 2013 with an endowment of 1.5 trillion won to foster science and technology that will lead Korea’s future. To date, a total of 706 research projects have received 923.7 billion won in funding, supporting approximately 14,000 researchers. So far, 2,600 papers have been published in international journals, including 450 papers in top-tier journals such as Science (9 papers), Nature (8 papers), and Cell (1 paper).
© The Asia Business Daily(www.asiae.co.kr). All rights reserved.
