Casimir vacuum energy at angstrom-scale crystal lattice gaps: a multi-oscillator Lifshitz screen of asymmetric layered materials

The Dzyaloshinskii-Lifshitz-Pitaevskii (DLP) Casimir formula is evaluated on the imagi- nary frequency axis using the Rakic 1998 Lorentz-Drude multi-oscillator dielectric func- tion for 26 metals and layered materials at their natural interplanar spacings (1. 8 to 7. 4 Å). The method is checked for consistency against one published measurement and one independent computational study. For the White et al. 2021 Cu-Cu engineered cavity at 1 µm, the computed energy density |E/A| agrees with the measured power output to within 10% under a single-rate-constant assumption. For the Moddel et al. 2021 Pd/NiO/Ni metal-insulator- metal (MIM) tunnel diode at 33 nm, the finite-plasma Drude shape ex- ponent extracted from the pipeline is α = −2. 39, consistent with a realistic dielectric (PC gives α = −3 exactly). The Casimir energy density at angstrom scale is ~4. 5×10⁸ times larger than at the White chip’s micrometer gap, after the Cu multi- oscillator di- electric suppression of 0. 4% relative to a perfect conductor is applied. An asymmetry figure of merit FOM = |E/A| × asymmetryfraction × abundancefactor is defined for en- gineered heterocavities and evaluated across 9 candidate platforms. Graphene / lithium- intercalated graphite (LiC₆) is identified as the top abundance-weighted intercalation heterocavity, with FOM = 8. 45×10⁻⁴ (eV/Ų), roughly 2. 4× the Cu-Au engineered metal heterocavity. A separate class of substitutionally doped commodity transition-metal hosts is then screened by a gap-extreme lattice- distortion model for seven heavy-element dopants (Sn, Sb, Te, Pb, Bi, Tl, Po) in two hosts (Ni and Co), yielding a new leader: Bi-doped Ni (and the degenerate Tl-doped Ni, same atomic radius) at FOM = 6. 46×10⁻³ eV/Ų, a factor of 7. 64× the graphene/LiC₆ value and produced from commodity materi- als already in industrial circulation. All computed numbers are lower bounds on the total van der Waals interaction: the DLP framework captures the retarded photon-pressure channel but is agnostic to non-retarded dispersion and short-range chemical overlap.