From Collaborator to Master of Major Scientific Equipment: Prof. Dr. Le Hong Khiem and Vietnam’s Mark in Dubna
Prof. Dr. Le Hong Khiem at JINR, Dubna (Russian Federation)
Vietnam became an official member of JINR in 1956, making it one of the organization’s longest-standing members. Over more than six decades of cooperation, numerous Vietnamese research institutes and universities have sent scientists to work at JINR, including VAST, the Vietnam Atomic Energy Institute (under the Ministry of Science and Technology), Hanoi University of Science and Technology, the University of Science - Vietnam National University, Hanoi, Vietnam National University, Ho Chi Minh City, Dalat University, and others.
VAST plays a core role in coordinating and promoting scientific cooperation with JINR, with the Institute of Physics serving as the main focal point. The Institute is responsible for organizing cooperation programs, selecting personnel to participate in research projects, and guiding the development of Vietnamese research groups. With a highly qualified scientific workforce and strengths in basic research, VAST has been - and continues to be - the strategic leader in Vietnam–JINR collaboration in fields such as nuclear physics, new materials, chemistry, biology, energy technology, and applied sciences.
Prof. Dr. Le Hong Khiem has played a pivotal role in advancing research cooperation between Vietnam and JINR. He is one of the few Vietnamese scientists to have successfully defended a doctoral thesis at JINR in 2011 and also served as the Plenipotentiary Representative of the Government of Vietnam to JINR from 2013 to 2022 - a strategic position that connected and fostered numerous bilateral cooperation programs.
Prof. Dr. Le Hong Khiem and Dr. Dmitry Kamanin, Director of JINR’s Postgraduate Training Center, at the JINR Information Center located at the Institute of Physics
Prof. Dr. Le Hong Khiem is currently a member of JINR’s Scientific Council - a group of distinguished scientists tasked with defining the institute’s research directions and scientific policies. In this capacity, he actively contributes to the development of strategic research programs in atomic nuclear physics and radiation applications, while promoting the alignment of JINR’s scientific objectives with Vietnam’s needs for scientific advancement and high-tech human resource training.
At present, Prof. Khiem continues to spend the majority of his time—between six and nine months each year - working directly at JINR to build and lead independent Vietnamese research groups, pursuing research directions that require the use of JINR’s most advanced facilities. This is a strategic step aimed at transforming the cooperation model from passive participation in international teams to proactively establishing and developing research groups led by Vietnamese scientists, thereby enhancing both the scientific standing and the substantive research capacity of Vietnam’s scientific community.
Prof. Dr. Le Hong Khiem stated: Only when we have independent research groups, capable of mastering research topics and proactively collaborating, can we truly harness the full potential of JINR to serve the practical and sustainable development of national science and technology. For this reason, he has worked diligently to establish and develop Vietnam’s first independent research group at JINR. This multidisciplinary group brings together talented young scientists from the Institute of Physics (VAST), the Vietnam Atomic Energy Institute, Dalat University, Vietnam National University - Ho Chi Minh City, Duy Tan University, and others. In his group, international experts participate only in the role of collaborators and technical supporters, while the Vietnamese team takes full initiative in designing research directions and controlling the experimental process. The use and operation of major facilities such as the IBR-2 nuclear reactor, the LINAC-800 accelerator, and the IREN high-intensity pulsed neutron source have enabled the group to carry out numerous projects aligned with Vietnam’s needs and strengths - from nuclear reactions and new materials development to environmental research.
At JINR, Prof. Dr. Le Hong Khiem’s group has pursued multiple research directions, three of which are currently the main focus. The first is the assessment of air pollution in provinces and cities across Vietnam using Barbula indica moss as a bioindicator, combined with modern analytical methods - particularly neutron activation analysis (NAA) at JINR’s IBR-2 nuclear reactor. This research direction was featured in the article “Prof. Dr. Le Hong Khiem uses moss as a bioindicator to study air pollution” (Science and Technology Bulletin No. 116 - August 2024). It represents an interdisciplinary approach, integrating nuclear physics, environmental science, and molecular biology to monitor and quantify trace element pollution in the air with high accuracy and long-term sustainability.
Moss Sample Preparation Process for NAA Analysis
The bioindicator moss method has been applied by the research group in various representative regions across Vietnam, including Hanoi, Hung Yen, Dong Nai, Hai Phong, Dalat, the Red River Delta, the central region, and the south-central coastal areas. In addition to sampling and elemental analysis using neutron activation, the group has integrated other modern techniques such as PIXE (Proton Induced X-ray Emission), TXRF (Total Reflection X-ray Fluorescence), and multivariate statistical analysis to identify sources of air pollutant emissions.
Bags containing samples of Barbula indica moss
Moss bags hung outdoors – bioindicators absorbing air pollutants
To date, the research group has published 11 papers in prestigious SCIE-listed international journals such as the Asia-Pacific Journal of Atmospheric Sciences, Journal of Radioanalytical and Nuclear Chemistry, Environmental Engineering and Management Journal, and Sains Malaysiana within this research direction. These works have accurately reflected the levels of heavy metal pollution in urban air, providing an important scientific basis for government agencies in formulating air pollution control policies.
MBR-1618R-BE X-ray irradiation system and beam geometry
The second research direction is the study of the structure and properties of new materials using neutron diffraction at the IBR-2 nuclear reactor. This advanced method is capable of analyzing crystal structures as well as the magnetic and electrical properties of materials at the atomic level - a critical condition for designing and optimizing functional materials in modern technology.
This direction focuses on investigating multifunctional materials such as ferroelectrics, multiferroics, manganites, magnetoelectric materials, and high-pressure materials. These material systems play an essential role in the development of electronic components, sensors, energy storage systems, and spintronic materials. In particular, neutron diffraction at IBR-2 has enabled the group to gain deep insights into phase transition mechanisms, magnetoelectric interactions, and microstructural features under extreme conditions such as high pressure, low temperature, or strong magnetic fields.
To date, this research direction has produced 19 SCIE-listed international publications in leading journals in materials science and solid-state physics, such as Journal of Alloys and Compounds, Journal of Electronic Materials, Ceramics International, Chemical Physics, Physical Review Materials, Physical Review B, and Journal of Physics and Chemistry of Solids. Notable works include a 2014 study on structural polymorphism in BiMnO₃ under high temperature and pressure, and a 2022 discovery of enhanced magneto-structural interactions in Mn₃O₄ under pressure.
Illustration of the crystal structure and magnetic spin orientation of Mn₃O₄ (orthorhombic Pbcm phase) under 20 GPa pressure, with antiferromagnetic chains in a zigzag pattern
A distinctive feature of this research direction is its continuity and depth, reflected in a series of closely connected studies linking changes in chemical composition, material processing conditions (such as doping, pressure, and temperature), and variations in physical properties. This approach clarifies the relationship between structure, properties, and applications. The group has also actively collaborated with domestic and international laboratories to expand the foundation of materials science, while simultaneously training high-level research personnel. These outcomes have opened up potential applications in the design of new materials for the electronics and energy industries.
The group’s third research direction at JINR, launched in 2024, focuses on studying nuclear reactions using the IREN high-intensity resonance neutron source - one of the few large neutron sources in the world. With its capability to generate neutron beams in resonance energy ranges at extremely high intensity, IREN enables advanced studies in fundamental nuclear physics, nuclear data research, and important applications for Vietnam’s nuclear energy development and radiation technologies. Prof. Dr. Le Hong Khiem emphasized that IREN is an essential facility for training highly qualified experts in nuclear energy - specialized human resources crucial for the development of nuclear power plants.
General schematic of IREN
From the very early stages of its deployment in 2024, the group designed and conducted numerous experiments using the IREN facility, publishing six scientific papers on new findings in the field of nuclear physics. Through experiments with IREN, young Vietnamese scientists have had the opportunity to participate directly in research from design and measurement to data analysis and the completion of scientific publications.
Although newly initiated, this research direction is opening up significant prospects not only for fundamental nuclear physics but also for potential applications in other areas such as nuclear technology, radiation safety, medical physics, and environmental studies. The effective utilization of IREN also demonstrates the group’s independent and proactive research capacity.
In 2025, Prof. Dr. Le Hong Khiem will spend nine months working at JINR to directly lead the Vietnamese team in designing dedicated research channels on the 800 MeV electron accelerator at the Laboratory of Nuclear Problems. This is a large-scale, state-of-the-art facility that is about to be commissioned. The Vietnamese team will be the first international research group to utilize this equipment. From the high-energy electron beams produced by the accelerator, the team will generate secondary radiation beams such as neutrons and gamma rays. These radiation sources will be used for nuclear physics research and radiation applications at Vietnamese institutes and universities. In the near future, this new direction is expected to make a practical contribution to training human resources for the nuclear energy development and application program promoted by the Government of Vietnam.
Prof. Dr. Le Hong Khiem at the control area of the 800 MeV electron accelerator, Laboratory of Nuclear Problems, JINR
Prof. Dr. Le Hong Khiem stated that the proposal from the Vietnamese team had received strong support and high appreciation from the leadership of the Laboratory of Nuclear Problems as well as from the JINR Directorate. At present, a series of nuclear physics and radiation application experiments are being designed to utilize Vietnam’s new research channels on this accelerator.
In addition to his research work, Prof. Dr. Le Hong Khiem actively participates in teaching and has supervised numerous doctoral candidates who have successfully defended their theses. A dedicated mentor, he has always been committed to building a team of young researchers with high professional competence and an international outlook. Under his guidance, many outstanding young researchers and doctoral students from universities and research institutes in Vietnam have had the opportunity to gain experience in JINR’s advanced scientific environment through key projects.
The research group model at JINR initiated by Prof. Dr. Le Hong Khiem has significantly helped to address the shortage of large-scale research equipment in Vietnam. This model not only enables Vietnamese scientists to proactively pursue practical research directions but also fosters sustainable connections with international partners. With strategic vision and persistent effort, Prof. Dr. Le Hong Khiem has contributed to affirming Vietnam’s genuine scientific capacity in large-scale international research programs, thereby enhancing the nation’s scientific standing.
Translated by Phuong Ha
Link to Vietnamese version
