Status of theoretical understanding

While scientists know the (1) chemical composition of the new class of superconductors, they (2) are less certain about how they work. True, a theory exists that explains low-temperature superconductivity. It is known as BCS from the initials of the authors John Bardeen and his colleagues Leon Cooper and Robert Schrieffer, who shared the 1972 Nobel Prize for physics for their effort.

In the microscopic theory of Bardeen–Cooper–Schrieffer, the presence of (3) a net attractive interaction between conduction electrons, which would normally repel each other because of their (4) like electrical charges, (5) is essential to the occurrence of super­conductivity. In conventional superconductors this (6) attraction originates in the dynamical motion of the crystal lattice which leads to unattractive "electron–photon–electron" inter­action. But the recent appearance of superconductivity in a class of materials quite different from the conventional superconductors, and with extremely high transition temperatures as well, has led physicists to explore a very wide spectrum of possible new (7) pairing mechanisms involving, for example, spin fluctuations, acoustic plasmons and excitonic processes.

The principle origin of the pairing "glue" (8) remains an open and to some extent crucial question. There is a wide range of theoretical possibilities and (9) the ultimate explanation may involve a combination of mechanisms. Indeed, some theorists (10) have discarded conventional BCS-theory and have suggested that there may not even be the traditional close relationship between (11) energy gaps and basic superconducting properties. It may take a considerable effort (12) to fully unravel the secrets of these compounds. Typical of the questions currently under active consideration are the role played by oxygen, the nature and scope of dynamical mechanisms and resulting electron pairing, whether this coupling is weak or strong, and whether the anisotropic nature of the materials is a truly important feature. The appearance of superconducting coherence lengths one or two orders of magnitude smaller than those previously encountered, the very low carrier concentrations, and the apparent importance of both copper and oxygen will probably require (14) a considerable extension of our current understanding of superconductivity. The fact that the superconducting interaction mechanism in the new materials is likely to be very different certainly (13) enhances the prospect that other high-temperature superconducting materials (HTSC) may be discovered.

1) Химический состав;

2) менее уверены;

3) суммарное взаимодействие притяжения;

4) сходные заряды;

5) существенно важно для возникновения;

6) притяжение зарождается;

7) механизм образования пар;

8) вопрос остаётся открытым и до некоторой степени критическим;

9) окончательное объяснение;

10) “развенчали” общепринятую теорию;

11) энергетические зоны;

12) полностью раскрыть секреты;

13) усиливать перспективу того, что…;

14) значительное расширение нашего современного представления