Technique for measuring the Cooper-pair velocity, density, and mass using Doppler splitting of the plasmon resonance in low-dimensional superconductor microstructures

The creation of a Cooper-pair mass spectroscopy is suggested. The plasmons in low-dimensional superconductor structures (layers or wires in the dielectric background) are theoretically considered for this purpose. The Cooper-pair mass ${\mathit{m}}^{\mathrm{*}}$ (the parameter ${\mathit{m}}^{\mathrm{*}}$ in London electrodynamics) can be determined by measurements of the Doppler shift of the plasmon frequency when a direct current is applied through the superconductor. The plasmons with frequency ω lower than the superconducting gap 2Δ can be detected by the same far-infrared absorption technique and grating coupling used previously for investigation of two-dimensional plasmons in semiconductor microstructures and polaritons in condensed-matter physics.