Superconductivity of thallium-doped lead telluride. Density of states in the valence band of thallium-doped and sodium-doped PbTe

Journal Article · Thu Oct 01 04:00:00 EDT 1981 · Sov. Phys. - Solid State (Engl. Transl.); (United States)

OSTI ID:5612780

Chernik, I; Lykov, S

Measurements of the low-temperature specific heat and Hall coefficient of p-type PbTe doped with the acceptor impurities thallium and sodium were used to find the density of states g in the valence band as a function of the Hall density of holes p/sub 77/ measured at T = 77 /sup 0/K. In the range p/sub 77/>4 x 10/sup 19/ cm/sup -3/ a considerable difference in g(p/sub 77/) was discovered between PbTe:Tl and PbTe:Na. The experimental results are interpreted in terms of the idea that the dominant perturbation of the band spectrum of PbTe by Na impurities (as distinct from Tl) is a considerable increase in the energy separation of the split-off ''heavy'' extremum in the valence band. The model under discussion gives a qualitative explanation of the reasons for the existence of bulk superconductivity in PbTe:Tl, as recently found by the present authors, and for its absence in PbTe:Na. Consequences of the present experimental results are examined and they are found to be relevant to the study of the properties of heavily doped semiconductors in both normal and superconducting states.

• Research Organization: M. I. Kalinin Polytechnic Institute, Leningrad
• OSTI ID: 5612780
• Journal Information: Sov. Phys. - Solid State (Engl. Transl.); (United States), Journal Name: Sov. Phys. - Solid State (Engl. Transl.); (United States) Vol. 23:10; ISSN SPSSA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
656102 -- Solid State Physics-- Superconductivity-- Acoustic
Electronic
Magnetic
Optical
& Thermal Phenomena-- (-1987)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALI METALS
ALLOYS
CHALCOGENIDES
CRYSTAL DOPING
DATA
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
ENERGY-LEVEL DENSITY
EXPERIMENTAL DATA
HALL EFFECT
INFORMATION
LEAD COMPOUNDS
LEAD TELLURIDES
METALS
NUMERICAL DATA
PHYSICAL PROPERTIES
SODIUM
SPECIFIC HEAT
SUPERCONDUCTIVITY
TELLURIDES
TELLURIUM COMPOUNDS
THALLIUM ADDITIONS
THALLIUM ALLOYS
THERMODYNAMIC PROPERTIES
VALENCE