Historical research guide · 0552 · 2023
Focus Fusion: Overview of Progress Towards p-B11 Fusion with the Dense Plasma Focus
Eric J. Lerner · Syed M. Hassan · Ivana Karamitsos-Zivkovic · Rudolph Fritsch
In one minute
Focus Fusion pairs a dense plasma focus with hydrogen–boron-11 fuel. A capacitor bank drives a current sheath through gas; it breaks into filaments, pinches, kinks and forms a magnetically self-confined plasmoid only tens of microns across. Lerner and colleagues report FF-1 measurements including mean confined ion energy of 240 ± 20 keV, an nτT estimate of 3.4 ± 0.8 × 10²⁰ keV-s/m³ and low impurity estimates after beryllium-electrode work. The paper argues that gigagauss magnetic fields could reduce X-ray cooling through Landau quantisation, based on calculations and simulations, and proposes direct energy conversion for a 5 MW generator. Those commercial conclusions and the p-B11 ignition path are designed or what-to-watch claims, not demonstrated power production.
Connection
This is the clearest published account of the plasmoid — the self-organised, magnetically self-confined ball of plasma that chapter 9 treats as the central object — written by the people who make them on purpose and measure them shot by shot. It also gives chapter 12 a fully aneutronic fusion route with real numbers attached, and chapter 13 a working example of the site’s thesis in miniature: let the plasma’s own instabilities do the concentrating instead of fighting them.
From the source
The dense plasma focus works by exploiting a chain of natural plasma instabilities rather than suppressing them: the current sheath breaks into filaments, the filaments converge into a single pinch, the pinch kinks, and the result is a magnetically self-confined plasmoid only tens of microns across that holds a substantial fraction of the energy fed into the device.Section ‘Dense Plasma Focus (DPF)’; the 2019 International Scientific Committee on Dense Magnetized Plasmas consensus statement
FF-1 plasmoids reached a mean confined ion energy of 240 keV plus or minus 20 keV, with isotropic neutron emission and a near-Gaussian neutron arrival-time distribution ruling out both an unconfined beam origin and a cold background plasma component.Section ‘World-Record Confined Ion Energy’; Fig. 7
Combining a 40 ns confinement time, an ion density bracketed between 3 and 4 times 10 to the 19th per cubic centimetre and the measured mean ion energy gives a density-confinement-temperature product of 3.4 plus or minus 0.8 times 10 to the 20th keV-s per cubic metre — the highest reported by any privately funded fusion effort.Section ‘Highest nτT Product Among Private Fusion Efforts’
Replacing tungsten electrodes with beryllium and then hand-polishing the anode to remove its oxide layer cut plasma impurities to a level giving an effective charge per ion of 1.004, measured by two independent spectrometer methods — by a wide margin the cleanest fusion plasma reported anywhere.Section ‘World Record Fusion Plasma Purity’; Figs. 8 and 9
The quantum magnetic field effect — Landau quantisation of electron energy levels in gigagauss fields — suppresses energy transfer from ions to electrons by as much as a factor of 25, cutting X-ray cooling by up to a factor of five and, in the team’s simulations, letting fusion power exceed bremsstrahlung by a factor of two so that hydrogen-boron-11 fuel can ignite.Section ‘Quantum Magnetic Field (QMF) Effect’; Equations 5 and 6; Fig. 3
Because p-B11 releases its energy entirely in charged particles and X-rays, a Focus Fusion generator can convert output directly — ion beam into a coil, X-rays into a multilayer photoelectric stack — giving a mass-producible 5 MW unit of roughly 3 tonnes at a capital cost near ten cents per watt.Sections ‘Energy Capture, Conversion to Electricity and Other Engineering Challenges’ and ‘Cost and Transition to a Fusion Economy’; Fig. 11
The way in
https://doi.org/10.1007/s10894-023-00345-zHow to cite it
Eric J. Lerner, Syed M. Hassan, Ivana Karamitsos-Zivkovic, Rudolph Fritsch (2023) Focus Fusion: Overview of Progress Towards p-B11 Fusion with the Dense Plasma Focus doi:10.1007/s10894-023-00345-z