Ultra-dense deuterium D(−1) is expected to be both a superfluid and a superconductor as shown by recent theoretical research. Condensed D(−1) can be deposited on surfaces by a source which produces a stream of clusters. A magnetic field strongly influences the type of material formed. Very little of D(−1) and of the form D(1), which is strongly coupled to D(−1), exists on the magnet surface or within several mm from the magnet surface. Even the formation of D(−1) on the source emitter is strongly influenced by a magnetic field, with a critical field strength in the range 0.03-0.07 T. Higher excitation levels D(2) and D(3) dominate in a magnetic field. The excitation level D(2) is now observed for the first time. The removal of D(−1) and D(1) in strong magnetic fields is proposed to be due to a Meissner effect in long D(−1) clusters by large-orbit electron motion. The lifting of long D(−1) clusters above the magnet surface is slightly larger than expected, possibly due to the coupling to D(1). The previously reported oscillation between D(−1) and D(1) in an electric field is proposed to be due to destruction of D(−1).

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The thermal ionization of a thick metal surface by pulsed multimegagauss magnetic field has been examined experimentally. Thick 6061-alloy Al rods with initial radii (R0) from 1.00 to 0.25 mm, larger than the magnetic field skin depth, are pulsed to 1.0 MA peak current in 100 ns. Surface fields (Bs) rise at 30−80 MG/μs and reach 1.5 and 4 MG, respectively. For this range of parameters, plasma forms at a threshold level of Bs=2.2 MG. Novel load hardware ensures that plasma formation is thermal, by Ohmic or compression heating. Surface-plasma formation is conclusively indicated through radiometry, extreme ultraviolet spectroscopy, and gated imaging. When R0=0.50 mm rods reach peak current, Bs=3 MG, the surface temperature is 20 eV, and Al3+ and Al4+ spectra and surface instabilities are observed. In contrast, R0=1.00 mm rod surfaces [Bs(t)<2.2 MG] reach only 0.7 eV and remain extremely smooth, indicating that no plasma forms.

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The first measurement of the threshold for thermal ionization of the surface of thick metal by pulsed magnetic field (B) is reported. Thick aluminum-with depth greater than the magnetic skin layer-was pulsed with partial differential B/ partial differential t from 30-80 MG/micros. Novel loads avoided nonthermal plasma (from electron avalanche, or energetic particles or photons from arcs). Thermal plasma forms from 6061-alloy aluminum when the surface magnetic field reaches 2.2 MG, in qualitative agreement with numerical simulation results by Garanin et al. [J. Appl. Mech. Tech. Phys. 46, 153 (2005)].