Anisotropic breakdown of Fermi liquid quasiparticle excitations in overdoped La2-xSrxCuO4

• High-temperature superconductivity emerges from an un-conventional metallic state. This has stimulated strong efforts to understand exactly how Fermi liquids breakdown and evolve into an un-conventional metal. A fundamental question is how Fermi liquid quasiparticle excitations break down in momentum space. Here we show, using angle-resolved photoemission spectroscopy, that the Fermi liquid quasiparticle excitations of the overdoped superconducting cuprate La1.77Sr0.23CuO4 is highly anisotropic in momentum space. The quasiparticle scattering and residue behave differently along the Fermi surface and hence the Kadowaki-Wood's relation is not obeyed. This kind of Fermi liquid breakdown may apply to a wide range of strongly correlated metal systems where spin fluctuations are present.

Keyword

High-Temperature Superconductors

Quantum Critical-Point

Normal-State

Cuprate Superconductors

Correlated Electrons

Surface

Bi2sr2cacu2o8+Delta

Tl2ba2cuo6+Delta

Transport

Behavior

Publication and Content Type

ref (subject category)

art (subject category)