Metal–insulator transitions

NOV 01, 1978

Changes in temperature, pressure, magnetic field or alloy composition can affect the electronic band structure of substances, in some cases leading to dramatic changes in conductivity.

DOI: 10.1063/1.2994815

Sir Nevill Mott

Research on metal–insulator transitions is at the moment quite fashionable. In many materials the electrical behavior changes from metallic to nonmetallic when the pressure, temperature or magnetic field is varied or (as in alloys) when the composition is varied, and the theoretical description of these processes is quite complicated. The interest of the problem lies perhaps mainly in our imperfect understanding of the nature of a metal. In the days before quantum mechanics, when I first attended undergraduate lectures on the electron theory of solids, it was taught that in metals one or more atoms from each electron were free, whereas in nonmetals they were somehow fixed to the atoms or ions or to the chemical bonds. The long mean free paths of electrons in metals extending over hundreds or thousands of atomic spacings were not understood, and neither was the absence of any large contribution from the electrons to the specific heat.

References

1. P. W. Anderson, Phys. Rev. 109, 1492 (1950).https://doi.org/PHRVAO
2. N. F. Mott, M. Pepper, S. Pollitt, R. H. Wallis, C. J. Adkins, Proc. R. Soc. A 345, 169 (1975).https://doi.org/PRLAAZ
3. C. J. Adkins, J. Phys. C 11, 851 (1978).https://doi.org/JPSOAW
4. N. F. Mott, Phil. Mag. 35, no. 111 (1977).https://doi.org/PHMAA4
5. N. F. Mott, Phil. Mag. B 37, 377 (1978).https://doi.org/PMABDJ
6. B. T. Debney, J. Phys. C 10, 4719 (1977).https://doi.org/JPSOAW
7. E. N. Economou, P. D. Antiniou, Solid St. Comm. 21, 285 (1977).https://doi.org/SSCOA4
8. A. Zylbersztejn, N. F. Mott, Phys. Rev. B 11, 4383 (1975).https://doi.org/PLRBAQ
9. C. Schlenker, B. K. Chakraverty, R. Buder, Proceedings of Int. Conf. on the Phys. of Semiconductors, Rome (1976), (F. G. Fumi, ed.), page 334;
C. Schlenker, S. Lakkis, S. Ahmed, J. L. Hodeau, M. Mariezio, J. Phys. C 10, 6151 (1977).https://doi.org/JPSOAW
10. Proceedings of the Summer School on “Metal–Insulator Transitions in Noncrystalline Systems,” held in St. Andrews, Scotland in August 1978, will be published by the University of Edinburgh Press early in 1979.

More about the Authors

Sir Nevill Mott. Cavendish Laboratory, Cambridge, U.K..