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An experimental physicist whose thin-film measurements helped motivate the theory of type-II superconductors. After changing the deposition procedure on Alexander Shalnikov's advice, Zavaritskii found critical-field behavior that differed from the familiar limiting case of Ginzburg-Landau theory. Discussion with Alexei Alexeyevich Abrikosov led to examining a different material-parameter regime, connecting a troublesome experiment with a new class of superconducting behavior.^[ref]

A type-II superconductor can admit magnetic flux through quantized vortices while retaining superconductivity between their cores. Its superconducting mixed state lies between the lower critical magnetic field and upper critical magnetic field. These are equilibrium bulk distinctions; sample shape, flux pinning and preparation affect a measured magnetic response.

The motivating thin-film experiments changed an apparently minor preparation detail. Nikolay Zavaritskii evaporated metal onto glass; Alexander Shalnikov proposed cooling the substrate to helium temperatures to suppress agglomeration. The resulting critical-field behavior no longer matched the small-parameter approximation. Alexei Alexeyevich Abrikosov found a different regime within the same theory, rather than discarding its equations.^[ref]