Researchers at Shanghai Jiao Tong University have made significant strides in neutron source technology, potentially revolutionizing applications in nuclear physics and energy sectors. Led by Zhiyu Lei from the Key Laboratory for Laser Plasmas and School of Physics and Astronomy, the team has proposed a novel method for generating quasi-monoenergetic high-flux neutron sources with remarkably short durations, on the order of femtoseconds.
The innovative approach utilizes an optical trap formed by two counter-propagating laser pulses, creating a density grating in a near-critical-density plasma. At an intensity of approximately 10^16 W/cm², deuteron ions are pre-accelerated to tens of keV. Following this, additional laser pulses, reaching intensities around 10^20 W/cm², boost these ions to the MeV energy level, facilitating efficient fusion reactions. This method is distinct from traditional pitcher-catcher configurations, allowing for effective collisions across the entire target volume, which enhances neutron production.
The research indicates that this technique can yield neutron pulses with energies ranging from 2 to 8 MeV, generating between 10^18 and 10^19 neutrons per second. The total neutron count can reach between 10^6 and 10^7 in a mere 400 femtoseconds, making it a powerful tool for various applications. “Such microsize femtosecond neutron pulses may find many applications, such as high-resolution fast neutron imaging and nuclear physics research,” Lei stated, emphasizing the broad potential of this advancement.
The unique angular distribution of the emitted neutrons, primarily aligned with the axis of the energy-boosting lasers, offers exciting opportunities for precision in imaging and experimental research. As the energy sector increasingly seeks efficient and compact neutron sources for a variety of applications, this development could lead to enhanced capabilities in energy production, safety assessments, and advanced materials research.
The findings were published in “Matter and Radiation at Extremes,” an academic journal focused on the intersection of materials science and radiation phenomena. For further details on the research team, you can visit their official page at Key Laboratory for Laser Plasmas and School of Physics and Astronomy, Shanghai Jiao Tong University.
