Abstract
While charge density wave (CDW) instabilities are ubiquitous to superconducting cuprates, the different ordering wave vectors in various cuprate families have hampered a unified description of the CDW formation mechanism. Here, we investigate the temperature dependence of the low-energy phonons in the canonical CDW-ordered cuprate La1.875Ba0.125CuO4. We discover that the phonon softening wave vector associated with CDW correlations becomes temperature dependent in the high-temperature precursor phase and changes from a wave vector of 0.238 reciprocal lattice units (r.l.u.) below the ordering transition temperature to 0.3 r.l.u. at 300 K. This high-temperature behavior shows that "214"-type cuprates can host CDW correlations at a similar wave vector to previously reported CDW correlations in non-214-type cuprates such as YBa2Cu3O6+δ. This indicates that cuprate CDWs may arise from the same underlying instability despite their apparently different low-temperature ordering wave vectors.
| Original language | English |
|---|---|
| Article number | 011008 |
| Journal | Physical Review X |
| Volume | 8 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 18 2018 |
| Externally published | Yes |
Funding
M.P.M.D. and H.M. acknowledge Philip Allen, Chris Homes, Jose Lorenzana, Claudio Mazzoli, Jurg Schmalian, and John Tranquada for insightful discussions. IXS research by H.M. and M.P.M.D. is supported by the Center for Emergent Superconductivity, an Energy Frontier Research Center funded by the U.S. Department of Energy (DOE), Office of Basic Energy Sciences. Work at Brookhaven National Laboratory was supported by the U.S. DOE, Office of Science, Office of Basic Energy Sciences, under Contract No.DE-SC00112704. The synchrotron radiation experiments were performed at BL43LXU in SPring-8 with the approval of RIKEN (Proposals No.20160097 and No.20170076).