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Spin-charge separation: From one hole to finite doping

Z. Y. Weng·D. N. Sheng·C. S. Ting
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Abstract

In the presence of nonlocal phase shift effects, a quasiparticle can remain topologically stable even in a spin-charge separation state due to the confinement effect introduced by the phase shifts at finite doping. True deconfinement only happens in the zero-doping limit where a bare hole can lose its integrity and decay into holon and spinon elementary excitations. The Fermi surface structure is completely different in these two cases, from a large band-structure-like one to four Fermi points in one-hole case, and we argue that the so-called underdoped regime actually corresponds to a situation in between.

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Z. Y. Weng, D. N. Sheng, C. S. Ting. 2001-01-26. Spin-charge separation: From one hole to finite doping. https://arxiv.org/abs/cond-mat/0101411

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