Historical research guide · 0842 · 2026
Stimulated Emission of Gravitational Waves via Dissimilar Superconducting Josephson Junctions
Gary V. Stephenson
In one minute
Gary Stephenson, an engineer at Seculine Consulting, sets out a buildable experiment for making gravitational waves on a laboratory bench instead of waiting for two black holes to collide. The device is a gaser — the gravitational counterpart of a laser — and Stephenson traces the idea through Halpern and Laurent in 1964, Lawrence Ford in 1982 and Giorgio Fontana in 2012. Its heart is a Josephson junction, a sandwich of two superconductors, with the two halves deliberately unlike each other: a plain s-wave superconductor such as lead joined to a d-wave cuprate such as YBCO. A pair crossing between those two symmetries has to change its orbital angular momentum by two units, and a spin-2 transition is exactly the transition that emits a graviton. One graviton is hopelessly rare, but Ford showed that coherent emitters add as the square of their number, so a wafer full of them is a different proposition. Stephenson then draws the wafer: thin films, a 24 gigahertz phased array, and the power and sensitivity budget for a first test.
Connection
Chapter 11 is the superconductor road to gravity control, and this paper is that road written as a parts list — named materials, a named frequency, a named wafer size and a named next measurement. It also gives chapter 4 something metric engineering usually lacks: a laboratory-scale source of gravitational radiation you could build in a university clean room, rather than an astrophysical event you can only wait for.
From the source
Josephson junctions built from dissimilar superconductors — an s-wave superconductor joined to a d-wave superconductor — can force spin-2 transitions and so trigger the emission of gravitational waves.Abstract; Section 4.3, Dissimilar Josephson Junctions
In the fully quantum treatment the radiated gravitational-wave power scales as the square of the number of coherent emitters, and because that number can be made arbitrarily large, quantum gravity effects can be macroscopically large rather than confined to Planck dimensions.Section 3, Equations 14 and 16 (Ford 1982)
Graviton emission in a superconducting junction is about 4.8 times ten to the minus forty-three of the photon emission probability for the same electron transition, but with a Cooper-pair density of ten to the twentieth per cubic centimetre in ten cubic centimetres of material, wavefunction coherence lifts graviton emission to the level of ordinary spontaneous photon emission in a single atom.Section 4.4, Emission Power Estimation (after Fontana 2012)
A thin-film lead and YBCO phased array driven at 24 gigahertz is estimated to emit about 121.5 milliwatts of gravitational-wave power on a 150 millimetre wafer and about 193.5 milliwatts on a 200 millimetre wafer.Section 5.3.1, Table 5
Reciprocity means the same junctions that are biased to emit high-frequency gravitational waves can be used passively to detect them; at a bandwidth of ten thousand hertz the noise equivalent power is about 600 picowatts, giving a signal-to-noise ratio better than 83 decibels for the 150 millimetre array.Section 5, opening; Section 5.3.2, Equation 18
The d-wave to s-wave conversion efficiency needed for graviton-to-photon conversion is not yet understood, so a range of doping regimes is recommended for experimental use to find the best approach; the remaining work is for the described hardware to be built and tested.Section 5.3.2, Quantum Efficiency of DJJs; Section 6, Conclusion
The way in
https://doi.org/10.4236/jhepgc.2026.121029How to cite it
Gary V. Stephenson (2026) Stimulated Emission of Gravitational Waves via Dissimilar Superconducting Josephson Junctions doi:10.4236/jhepgc.2026.121029