Superconductivity: Quantum Uncertainty of the Number of Carriers and Stability of the Superconducting Phase
( Pp. 312-321)

More about authors
Rakhimov Rustam Kh. Dr. Sci. (Eng.); Head, Laboratory No. 4, Institute of Materials Science; Academy of Sciences of the Republic of Uzbekistan; Tashkent, Republic of Uzbekistan
Академия наук Республики Узбекистан
г. Ташкент, Республика Узбекистан Yermakov Vladimir P. senior research, Laboratory No. 4, Institute of Materials Science; Academy of Sciences of the Republic of Uzbekistan; Tashkent, Republic of Uzbekistan
Abstract:
The article addresses the conceptual link between quantum uncertainty in the number of charge carriers and the stability of the macroscopic superconducting phase. It is shown that a condensate of Cooper pairs characterized by a well-defined global phase is mathematically equivalent to a superposition of states with different pair numbers, so that local charge is effectively delocalized across the condensate. Building on this premise, the paper develops the notion of superconductor polarizability as a parameter governing the energetic cost of charge redistribution and, consequently, the critical characteristics of the material – critical current Ic and critical field Hc. Four classes of systems in which number-phase fluctuations are particularly pronounced are examined: thin films, granular superconductors, cuprates, and high-pressure hydrides. Experimental techniques for detecting these fluctuations (STM/STS spectroscopy, impedance spectroscopy, noise measurements) and the relevant theoretical frameworks (BCS theory, Ginzburg–Landau theory, strong-correlation models) are reviewed. The conclusion argues that superconductivity stability is governed by the balance between phase coherence and the energetic penalty for charge localization, and justifies the requirement for a comprehensive assessment of phase stiffness when evaluating claims of high-temperature superconductivity.
How to Cite:
Rakhimov R.Kh. and Yermakov V.P. Superconductivity: Quantum uncertainty of the number of carriers and stability of the superconducting phase. Computational Nanotechnology. 13, 2 (2026), 312–321. DOI: 10.33693/2313-223X-2026-13-2-312-321. EDN: XERUIY
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Keywords:
superconductivity, number-phase uncertainty relation, charge fluctuations, polarizability, critical current, super insulator, Cooper pairs, thin films.