TDHF and LENR

TDHF and a Macroscopic Aspect of Low-Energy Nuclear Reactions

Kouhei Washiyama1, Kazuyuki Sekizawa2,3

1Research Center for Superheavy Elements, Kyushu University, Fukuoka, Japan

2Center for Transdisciplinary Research, Institute for Research Promotion, Niigata University, Niigata, Japan

3Division of Nuclear Physics, Center for Computational Sciences, University of Tsukuba, Ibaraki, Japan

Abstract

Time-dependent Hartree--Fock (TDHF) method has been applied to various low-energy nuclear reactions, such as fusion, fission, and multinucleon transfer reactions. In this Mini Review, we summarize recent attempts to bridge a microscopic nuclear reaction theory, TDHF, and a macroscopic aspect of nuclear reactions through nucleus--nucleus potentials and energy dissipation from macroscopic degrees of freedom to microscopic ones obtained from TDHF in various colliding systems from light to heavy mass regions.

11 pages, 2 figures; accepted for publication in Research Topic "Advances in Time-Dependent Methods for Nuclear Structure and Dynamics" in Frontiers in Physics

Subjects: Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)

DOI: 10.3389/fphy.2020.00093

Frontiers in Physics

TDHF and a Macroscopic Aspect of Low-Energy Nuclear Reactions

Time-dependent Hartree–Fock (TDHF) method has been applied to various low-energy nuclear reactions, such as fusion, fission, and multinucleon transfer…

www.frontiersin.org

I cannot find a reference to this at https://lenr-canr.org/ or a thread discussing it here. The authors are well established in their respective fields. I'm interested to know of any CMNS researchers working with these theorists.

Also

Quote

Time-dependent Hartree--Fock (TDHF) method has been applied to various low-energy nuclear reactions, such as fusion, fission, and multinucleon transfer reactions.- end quote

I'd like to learn more about TDHF...

It's use both in and outside the field of CMNS/LENR. The Google/DoE and GEC/DoD patents technologies include various low-energy nuclear reactions, such as fusion, fission, and multinucleon transfer reactions; similar concepts found in this paper.

Posted on this thread because both are old news. Not related at all. Just thing to catch up on and see if I learn anything new.

THz tech is new... The field has matured quickly and well worth keeping up with.

Yes, perhaps another useful - tool Nano THz sensors and emitters.

Source

Lawrence Livermore National Laboratory

Report 2016

Spin-Based Broadband Terahertz Radiation from Topological Insulators

Dongxia Qu (15-LW-018)

Abstract

Terahertz radiation falls in between infrared and microwave radiation in the electromagnetic spectrum. Like microwave radiation, terahertz radiation can penetrate a wide variety of nonconducting materials. The terahertz (THz) region, referred to as the wavelengths from 15 μm to 1 mm, remains one of the least-developed spectral regions, although proof-of-principle experiments have advanced its potential in a wide variety of application areas including homeland security, nondestructive evaluation, detection of explosives and noxious gases, medical imaging, material characterization, and broadband wireless communications. The three existing techniques for generation of broadband terahertz waves are: surface-field emission from semiconductors, photoconductive antennas, and optical rectification of ultrafast laser pulses. However, the bandwidth of terahertz emission generated by these techniques is typically limited to below 5 THz. The search for broader-band terahertz sources calls for new materials and mechanisms. Our objective was to develop a new mechanism of broadband terahertz radiation for national defense applications by taking advantage of the chiral spin texture of a new quantum state-of-matter topological insulator. A topological insulator is a material that behaves as an insulator in its interior, but whose surface contains conducting states, meaning that electrons can only move along the surface of the material. We used a photo-excited topological insulator heterostructure to generate a spin current, whose temporal evolution is dramatically faster than that of charge currents in conventional terahertz emitters. The resulting transient spin current can be converted into a broadband terahertz pulse via the inverse spin Hall effect. We demonstrated this spin–charge conversion mechanism in a proof-of-concept topological insulator with a gallium-arsenide heterostructure (a structure in which two semiconductor materials are grown into a "sandwich"). We discovered that the photo-induced spins can be driven from a topological insulator into an adjacent nonmagnetic semiconductor at room temperature. The interface spin transport leads to an inverse spin Hall photocurrent with a magnitude that is much larger and can be greatly modulated with an external electric field. The sensitivity of photocurrent to an external gate field, together with the observation of a distinct temperature-dependent photocurrent profile, allow us to isolate the interface spin transport solely arising from surface states, which were difficult to probe in microwave spin-pumping experiments. Our results provided the first experimental evidence to unambiguously isolate surface inverse-spin Hall current from the bulk contribution. In particular, we demonstrated the possibility to realize interface spin transport by seamlessly integrating a topological insulator thin film with a normal semiconductor. This possibility is of general interest in both fundamental physics and technological applications toward broadband terahertz generation and the emerging field of “topotronics,” in which quantum mechanical degrees of freedom are employed that allow for highly conducting dissipation-free channels at the surface of materials that would otherwise be insulating in their bulk.