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Angle-resolved photoemission study of quasi-one-dimensional superconductor $β$-Na$_{0.33}$V$_2$O$_5$

K. Okazaki·A. Fujimori·T. Yamauchi·Y. Ueda
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Abstract

We have studied the electronic structure of $β$-Na$_{0.33}$V$_2$O$_5$, which becomes a superconductor under pressure, by angle-resolved photoemission spectroscopy. Clear band dispersions is observed only along the chain direction, indicating the quasi-one-dimensional (1D) electronic structure. The spectra of the V 3d band are dominated by a Gaussian-like broad feature at $\sim$ 1 eV below the Fermi level ($E_F$) with negligible intensity at $E_F$, which we attribute to strong electron-phonon coupling as in other 1D polaronic metals. In the momentum space, the spectra show a maximum intensity at $k \sim \pm π/4b$, where $b$ is the V-V distance along the b-axis, reflecting the band filling of the chain and/or ladder.

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K. Okazaki, A. Fujimori, T. Yamauchi, Y. Ueda. 2003-08-19. Angle-resolved photoemission study of quasi-one-dimensional superconductor $β$-Na$_{0.33}$V$_2$O$_5$. https://doi.org/10.1103/physrevb.69.140506

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