Thallium magnetic resonance in superconducting <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi mathvariant="normal">Tl</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi mathvariant="normal">Ba</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi mathvariant="normal">Ca</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi mathvariant="normal">Cu</mi></mrow><mrow><mn>3</mn></mrow></msub></mrow></math><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi mathvariant="normal">O</mi></mrow><mrow><mn>1</mn><mn>0</mn><mo>+</mo><mi mathvariant="normal">δ</mi></mrow></msub></mrow></math>

Moohee Lee; Y.-Q. Song; W. P. Halperin; Lauren M. Tonge; Tobin J. Marks; Henry O. Marcy; C. R. Kannewurf

doi:10.1103/PhysRevB.40.817

Rapid Communication

Thallium magnetic resonance in superconducting ${Tl}_{2}$ ${Ba}_{2}$ ${Ca}_{2}$ ${Cu}_{3}$ $O_{10 + δ}$

Moohee Lee, Y.-Q. Song, W. P. Halperin, Lauren M. Tonge, Tobin J. Marks, Henry O. Marcy, and C. R. Kannewurf

Phys. Rev. B 40, 817(R) – Published 1 July 1989

Abstract

Significant frequency shifts of the thallium nuclear-magnetic-resonance (NMR) spectrum have been observed in the super- conducting state of the high-temperature superconductor ${Tl}_{2}$ ${Ba}_{2}$ ${Ca}_{2}$ ${Cu}_{3}$ $O_{10 + δ}$ . Measurements at two different magnetic fields indicate that the origin of these shifts is mainly due to the field distribution associated with vortices in the mixed state. The spin-lattice relaxation measurements are consistent with an anisotropic energy gap. The NMR linewidth varies significantly with temperature and magnetic field, apparently inconsistent with the BCS theory.