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High-pressure superconducting phase diagram of 6Li: isotope effects in dense lithium.

ABSTRACT: We measured the superconducting transition temperature of (6)Li between 16 and 26 GPa, and report the lightest system to exhibit superconductivity to date. The superconducting phase diagram of (6)Li is compared with that of (7)Li through simultaneous measurement in a diamond anvil cell (DAC). Below 21 GPa, Li exhibits a direct (the superconducting coefficient, ?, T(c) ?proportional M(-?), is positive), but unusually large isotope effect, whereas between 21 and 26 GPa, lithium shows an inverse superconducting isotope effect. The unusual dependence of the superconducting phase diagram of lithium on its atomic mass opens up the question of whether the lattice quantum dynamic effects dominate the low-temperature properties of dense lithium.

SUBMITTER: Schaeffer AM

PROVIDER: S-EPMC4291671 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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High-pressure superconducting phase diagram of 6Li: isotope effects in dense lithium.

Schaeffer Anne Marie AM Temple Scott R SR Bishop Jasmine K JK Deemyad Shanti S

Proceedings of the National Academy of Sciences of the United States of America 20141223 1

We measured the superconducting transition temperature of (6)Li between 16 and 26 GPa, and report the lightest system to exhibit superconductivity to date. The superconducting phase diagram of (6)Li is compared with that of (7)Li through simultaneous measurement in a diamond anvil cell (DAC). Below 21 GPa, Li exhibits a direct (the superconducting coefficient, α, T(c) proportional M(-α), is positive), but unusually large isotope effect, whereas between 21 and 26 GPa, lithium shows an inverse su ...[more]

PMID: 25538300

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