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Induced local spin-singlet amplitude and pseudogap in high $T_{c}$ cuprates

Bumsoo Kyung
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Abstract

In this paper we show that local spin-singlet amplitude with d-wave symmetry, $<|Δ_{d}(0)|^{2}>$, can be induced by short-range spin correlations even in the absence of pairing interactions. Fluctuation theory is formulated to make connection between pseudogap temperature $T^{*}$, pseudogap size $Δ_{pg}$ and $<|Δ_{d}(0)|^{2}>$. In the present scenario for the pseudogap, the normal state pseudogap is caused by the induced local spin-singlet amplitude due to short-range spin correlations, which compete in the low energy sector with superconducting correlations to make $T_{c}$ go to zero near half-filling. Calculated $T^{*}$ falls from a high value onto the $T_{c}$ line and closely follows mean-field Néel temperature $T_{N}^{MF}$. The calculated $Δ_{pg}$ is in good agreement with experimental results. We propose an experiment in which the present scenario can be critically tested.

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Bumsoo Kyung. 2001-08-24. Induced local spin-singlet amplitude and pseudogap in high $T_{c}$ cuprates. https://doi.org/10.1103/physrevb.64.104512

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