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Operator Projection Theory for Electron Differentiation in Underdoped Cuprate Superconductors

Shigeki Onoda·Masatoshi Imada
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Abstract

Metals approaching the Mott insulator generate a new hierarchy in the electronic structure accompanied by a momentum dependent electron differentiation, beyond the Mott-Hubbard, Brinkman-Rice and Slater pictures of the Mott transition. To consider such nonlinear phenomenon, we develop an analytic nonperturbative theory based on operator projections combined with a self-consistent treatment of the low-energy excitations. This reproduces the formation of the Hubbard bands, Mott gap, spin fluctuations, mass divergence, diverging charge compressibility, and strongly renormalized flat and damped dispersion similar to angle-resolved photoemission data in high-T_c cuprates. Main structures in electronic spectra show a remarkable similarity to numerical results.

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Shigeki Onoda, Masatoshi Imada. 2001-08-27. Operator Projection Theory for Electron Differentiation in Underdoped Cuprate Superconductors. https://doi.org/10.1016/s0022-3697(02)00248-2

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