Electronic structure of underdoped cuprates

Abstract

We consider a two-dimensional Fermi liquid coupled to low-energy commensurate spin fluctuations. At small coupling, the hole Fermi surface is large and centered around $Q =(\pi,\pi)$. We show that as the coupling increases, the shape of the quasiparticle Fermi surface and the spin-fermion vertex undergo a substantial evolution. At strong couplings, $g \gg \omega_0$, where $\omega_0$ is the upper cutoff in the spin susceptibility, the hole Fermi surface consists of small pockets centered at $(\pm \pi/2, \pm \pi/2)$. Simultaneously, the full spin-fermion vertex is much smaller than the bare one, and scales nearly linearly with $|q-Q|$, where $q$ is the momentum of the susceptibility. At intermediate couplings, there exist both, a large hole Fermi surface centered at $(\pi,\pi)$, and four hole pockets, but the quasiparticle residue is small everywhere except for the pieces of the pockets which face the origin of the Brillouin zone. The relevance of these results for recent photoemission experiments in $YBCO$ and $Bi2212$ systems is discussed.Comment: 19 pages, RevTeX, 15 figures embedded in the text, submitted to Phys. Rep., ps-file is also available at http://lifshitz.physics.wisc.edu/www/morr/morr_homepage.htm

Fermi surface reconstruction in high-Tcsuperconductors

“…The simplest case to visualize is commensurate (π, π) antiferromagnetic order, which would cause the large hole-like Fermi surface of cuprates to be reconstructed into small hole and electron pockets [20], located respectively at (π/2, π/2) and (π, 0), as sketched in Fig. 1b.…”

Fermi surface reconstruction in hole-dopedt−Jmodels without long-range antiferromagnetic order

“…[7][8][9] One possible, well known route to a Fermi surface reconstruction is the onset of spin-density wave (SDW) order, which breaks a large Fermi surface into small electron-and hole-pockets centered at the magnetic Brillouin zone boundary. 10,11 In fact, many of the unresolved theoretical problems in strongly correlated electron materials, from heavy-Fermion compounds to high-T c cuprates, are related to the fate of electronic excitations close to antiferromagnetic quantum critical points. 12 It has been been argued, however, that the critical point between a metal with a large Fermi surface and an antiferromagnetic metal with small Fermi pockets may be replaced by a new intermediate phase, the so called fractionalized Fermi liquid (FL*) 13,14 , which exhibits small pockets similar to the antiferromagnetic metal, but breaks no symmetries: summaries of these arguments, and of previous theoretical work, can be found in two recent reviews.…”

Фрустрированный $J_{1}$-$J_{2}$-$J_{3}$ Квантовый Двумерный Антиферромагнетик В Сферически-Симметричном Самосогласованном Подходе

“…Аналогичная форма феноменологической спиновой восприимчивости используется в теории почти АФМ ферми-жидкости [26]- [28]. Вблизи страйп-фазы соответству-ющие разложения должны проводиться около точки X. В случае модели J 1 фурье-образ M (q, ω) определяется трехузельной неприводи-мой функцией Грина ⟨δb z q | δb z −q ⟩ ω с оператором δb z q следующего вида [17]:…”

“…В случае p = 0.28: штрих-пунктирные линии -ω p=0. 28 ac,opt (q); сплошные линии -спектры ω p=0.28 ac,opt (q), опре-деляемые по положениям пиков у χ ′′ ac,opt (q, ω) (ср. со сплошными линиями на рисунке a).…”