Starting from the effective low-energy theory of a doped Mott insulator, obtained by exactly integrating out the high-energy scale, we show that the effective carrier density in the underdoped regime agrees with a two-fluid description. Namely, it has distinct temperature-independent and thermally activated components. We identify the thermally activated component as the bound state of a hole and a charge- 2e boson, which occurs naturally in the effective theory. The thermally activated unbinding of this state leads to the strange metal and subsequent T -linear resistivity. We find that the doping dependence of the binding energy is in excellent agreement with the experimentally determined pseudogap energy scale in cuprate superconductors.
|Original language||English (US)|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - Oct 30 2009|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics