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Pseudogap phase in the U(1) gauge theory with incoherent spinon pairs

Xi Dai·Yue Yu·Tao Xiang·Zhao-bin Su
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Abstract

The pseudogap effect of underdoped high-$T_c$ superconductors is studied in the U(1) gauge theory of the t-J model including the spinon pairing fluctuation. The gauge fluctuation breaks the long range correlation between the spinon pairs. The pairing fluctuation, however, suppresses significantly the low-lying gauge fluctuations and leads to a stable but phase incoherent spin gap phase which is responsible for the pseudogap effects. This quantum disordered spin gap phase emerges below a characteristic temperature $T^{*}$ which is determined by the effective potential for the spinon pairing gap amplitude. The resistivity is suppressed by the phase fluctuation below $% T^{*}$, consistent with experiments.

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Xi Dai, Yue Yu, Tao Xiang, Zhao-bin Su. 1999-04-09. Pseudogap phase in the U(1) gauge theory with incoherent spinon pairs. https://doi.org/10.1103/physrevb.61.8683

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