Opening a nodal gap by fluctuating spin-density-wave in lightly doped La$_{2-x}$Sr$_x$CuO$_4$

Itzik Kapon; David S. Ellis; Gil Drachuck; Galina Bazalitski; Eugen Weschke; Enrico Schierle; Jörg Strempfer; Christof Niedermayer; Amit Keren

doi:10.1103/physrevb.95.104512

arXiv · 1612.06864

Opening a nodal gap by fluctuating spin-density-wave in lightly doped La$_{2-x}$Sr$_x$CuO$_4$

Itzik Kapon·David S. Ellis·Gil Drachuck·Galina Bazalitski·Eugen Weschke·Enrico Schierle·Jörg Strempfer·Christof Niedermayer·Amit Keren

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Abstract

We investigate whether the spin or charge degrees of freedom are responsible for the nodal gap in underdoped cuprates by performing inelastic neutron scattering and x-ray diffraction measurements on La$_{2-x}$Sr$_x$CuO$_4$, which is on the edge of the antiferromagnetic phase. We found that fluctuating incommensurate spin-density-wave (SDW) with a the bottom part of an hourglass dispersion exists even in this magnetic sample. The strongest component of these fluctuations diminishes at the same temperature where the nodal gap opens. X-ray scattering measurements on the same crystal show no signature of charge-density-wave (CDW). Therefore, we suggest that the nodal gap in the electronic band of this cuprate opens due to fluctuating SDW with no contribution from CDW.

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Itzik Kapon, David S. Ellis, Gil Drachuck, Galina Bazalitski, Eugen Weschke, Enrico Schierle, Jörg Strempfer, Christof Niedermayer, Amit Keren. 2016-12-20. Opening a nodal gap by fluctuating spin-density-wave in lightly doped La$_{2-x}$Sr$_x$CuO$_4$. https://doi.org/10.1103/physrevb.95.104512

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