Nonmonotonic pseudogap in high-T-c cuprates
Research output: Contribution to journal › Research article › Contributed › peer-review
Contributors
Abstract
The mechanism of high-temperature superconductivity has not been resolved for so long because the normal state of cuprates, which exhibits enigmatic pseudogap phenomena, is not yet understood. We performed careful temperature- and momentum-resolved photoemission experiments to show that the depletion of the spectral weight in slightly underdoped cuprate superconductor, usually called the "pseudogap," exhibits an unexpected nonmonotonic temperature dependence: decreases linearly approaching T-* at which it reveals a sharp transition but does not vanish and starts to increase gradually again at higher temperature. The low-temperature behavior of the pseudogap is remarkably similar to one of the incommensurate charge ordering gap in the transition-metal dichalcogenides, while the reopening of the gap at room temperature fits the scenario of temperature-driven metal-insulator transition. This observation suggests that two phenomena, the electronic instability to density-wave formation and the entropy-driven metal-to-insulator crossover, may coexist in the normal state of cuprates.
Details
Original language | English |
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Article number | 020504 |
Number of pages | 4 |
Journal | Physical Review B |
Volume | 79 |
Issue number | 2 |
Publication status | Published - Jan 2009 |
Peer-reviewed | Yes |
Externally published | Yes |
External IDs
Scopus | 59249091688 |
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Keywords
Keywords
- bismuth compounds, calcium compounds, entropy, high-temperature superconductors, lead compounds, metal-insulator transition, phase diagrams, photoelectron spectra, strontium compounds, superconducting energy gap, terbium compounds, STATE