Evidence for a vestigial nematic state in the cuprate pseudogap phase
2019; National Academy of Sciences; Volume: 116; Issue: 27 Linguagem: Inglês
10.1073/pnas.1821454116
ISSN1091-6490
AutoresSourin Mukhopadhyay, Rahul Sharma, Chung Koo Kim, Stephen Edkins, Mohammad Hamidian, Hiroshi Eisaki, Shin‐ichi Uchida, Eun-Ah Kim, Michael J. Lawler, A. P. Mackenzie, J. C. Davis, Kazuhiro Fujita,
Tópico(s)Magnetic properties of thin films
ResumoThe CuO$_2$ antiferromagnetic insulator is transformed by hole-doping into an exotic quantum fluid usually referred to as the pseudogap (PG) phase. Its defining characteristic is a strong suppression of the electronic density-of-states D(E) for energies |E|<$\Delta^*$, where $\Delta^*$ is the pseudogap energy. Unanticipated broken-symmetry phases have been detected by a wide variety of techniques in the PG regime, most significantly a finite Q density-wave (DW) state and a Q=0 nematic (NE) state. Sublattice-phase-resolved imaging of electronic structure allows the doping and energy dependence of these distinct broken symmetry states to be visualized simultaneously. Using this approach, we show that, even though their reported ordering temperatures T$_{DW}$ and T$_{NE}$ are unrelated to each other, both the DW and NE states always exhibit their maximum spectral intensity at the same energy, and using independent measurements that this is the pseudogap energy $\Delta^*$. Moreover, no new energy-gap opening coincides with the appearance of the DW state (which should theoretically open an energy gap on the Fermi-surface), while the observed pseudogap opening coincides with the appearance of the NE state (which should theoretically be incapable of opening a Fermi-surface gap). We demonstrate how this perplexing phenomenology of thermal transitions and energy-gap opening at the breaking of two highly distinct symmetries can be understood as the natural consequence of a vestigial nematic state , within the pseudogap phase of Bi$_2$Sr$_2$CaCu$_2$O$_8$.
Referência(s)