Josephsonstroom

Josephsonstroom is a term used in some theoretical discussions and popular science to denote the current that flows through a superconducting Josephson junction as described by the Josephson relations. The term blends the surname Josephson with the Dutch word stroom (current), and is not a standard, universally accepted designation in mainstream superconductivity literature.

In essence, Josephsonstroom refers to the phase-coherent current that flows without dissipation when the junction is biased below its critical current Ic, I = Ic sin(phi). Under a constant voltage V, the phase evolves as phi(t) = phi0 + (2eV/ħ) t, producing an alternating current component at frequency f = 2eV/ħ. When the bias or drive is time-dependent, the current contains harmonics and can exhibit Shapiro steps.

In mathematical terms, the current through a single Josephson junction under voltage drive is described by I(t) = Ic sin(phi(t)), with dphi/dt = (2e/ħ) V(t). For V(t) = Vdc + Vac cos(ωt), solutions lead to step-like features in the I-V curve at V = nħω/(2e).

Usage and status: The term "Josephsonstroom" is not part of the rigorous nomenclature; it appears mainly in informal writings or as a hypothetical construct in discussions of phase-coherent transport in Josephson networks. The standard terminology remains "Josephson current" or "supercurrent."

See also: Josephson effect, Josephson junction, superconductivity, Shapiro steps, quantum circuits.