Records for conversion of laser energy to nuclear energy in exploding nanostructures

Significance Statement

Top-table nuclear fusion reactions in the chemical physics laboratory have been driven by high-energy dynamics of Coulomb exploding deuterium containing nanostructures produced through femtosecond, near-infrared ultra-intense laser pulses. The need for nuclear fusion initiated by surface chemical reactions is accelerated by several experimental as well as conceptual failures.

Failed attempts recorded previously have been because there is no evidence to support any practical mechanism of nuclear fusion in the energy domain of chemical reactions. However, there has emerged compelling theoretical as well as experimental evidence for table-top nuclear fusion driven by Coulomb explosion of nanostructured assemblies, for instance, nano-droplets and clusters that are driven by ultra-intense femtosecond lasers. The ultra-intense laser pulses for producing sufficient Coulomb explosion for these nanostructures have been characterized by high intensities of more than 1021 Wcm-2, which can be generated from the available Terawatt and Petawatt lasers.

The interaction of nanometer-sized components with the ultra-intense near-infrared lasers leads to outer and inner ionization of nanostructures, which is then followed by Coulomb explosion that generates high-energy ions in the domain of nuclear physics.

Professor Joshua Jortner and Professor Isidore Last at Tel Aviv University investigated the conditions favoring the attainment of high efficiencies for table-top conversion of laser energy to nuclear energy mediated by Coulomb explosion dynamics for molecular droplets. Their computational and theoretical analysis for fusion of deuterium with 7Li, 6Li, and deuterium atoms within the source-target design led to the highest efficiencies for table-top nuclear fusion achieved to date. Their research work is published in Chemical Physics Letters.

In the source-target reaction design, the source was composed of deuterons generated by Coulomb explosion of deuterium nano-droplets, impinging on a hollow target with 7Li, 6Li and deuterium atoms. Jortner and Last considered fusion reactions with the highest cross-sections in the required energy domain. The cylindrical target entailed 7Li or 6Li for deuterium reaction with lithium isotopes, and deuterium film or deuterated polyethylene polymer.

The authors demonstrated the improvement of 4-6 order of magnitude of the conversion efficiency of laser energy to nuclear energy for the proposed source-target design within a source of deuterium nano-droplets compared to low experimental values within the nanoplasma produced by Coulomb explosion of deuterium.

Their theoretical and computational analysis posted the achievement of high fusion efficiencies in the range of 10J-1, as well as energy conversion coefficient in the range of 10-2-10-3, for the fusion reaction of deuterium with 7Li, 6Li and deuterium atoms within the source-target reaction design. These values constitute the highest table-top fusion reaction yields and efficiencies recorded to date. The source-target design with an exploding nano-droplets source initiated by a superintense laser and a hollow cylinder target, offered the most efficient device for the table-top conversion of laser energy to nuclear energy.

The results obtained in their study will motivate a future comparison between the theoretical-computational outcomes recorded by the authors and experimental reality.

About The Author

Professor Joshua Jortner received his Ph.D. from the Hebrew University of Jerusalem in 1960.  From 1973-2003 he served as the Heinemann Professor of Chemistry at the School of Chemistry of Tel Aviv University in Israel.  He has held visiting Professorships at the University of Chicago, the University of Copenhagen, and the University of California, Berkeley.  He was the Christensen Visiting Fellow at  Oxford University, served in the International Research Chair “Blaise Pascal”, France, and as a Humboldt Fellow at the Humboldt University, Berlin.

Jortner holds honorary doctorates from seven Universities in Israel, France and Germany.  Among his awards are the International Academy of Quantum Science Award, the Israel Prize in Exact Sciences, the Wolf Prize in Chemistry, the Honorary J. Heyrovsky‎‎ Medal, the von Hofmann Medal, the Robert S. Mulliken Medal, the Joseph O. Hirschfelder Prize, the Maria Sklodowsky-Curie Medal, and the Lise Meitner Research Award of the Alexander von Humboldt Foundation.

A member of the Israeli Academy of Sciences and Humanities, Jortner is a foreign honorary member of the Academies of Sciences of Denmark, Poland, Romania, Russia, India, the Netherlands, the Czech Republic, the Leopoldina National Academy of Germany, the Italian Accademia Nazionale dei Lincei, the International Academy of Quantum Molecular Sciences, the American Philosophical Society, the American Academy of Arts and Sciences and the National Academy of Sciences of the USA.  He held many honorary lectureships in Europe, Asia, the United States and Israel.

Jortner served as President of the Israel Academy of Sciences and Humanities (1986-1995), and as the Founding President of the Israel Science Foundation. He served as the President of the International Union of Pure and Applied Chemistry (1998-2000).

His research centers on the exploration of the phenomena of energy acquisition, storage and disposal in isolated molecules, clusters, nanostructures, condensed phases and biophysical systems.

Reference

Joshua Jortner and Isidore Last. Records for conversion of laser energy to nuclear energy in exploding nanostructures. Chemical Physics Letters, volume 683 (2017), pages 281–285.

Go To Chemical Physics Letters