Characterization of photoinduced normal state through charge density wave in superconducting YBa$_2$Cu$_3$O$_{6.67}$

TL;DR

This study investigates the photoinduced normal state in high-Tc cuprate YBa$_2$Cu$_3$O$_{6.67}$ using time-resolved x-ray scattering, revealing that photoexcitation induces charge density wave phenomena similar to those observed under magnetic fields.

Contribution

It demonstrates that photoinduced normal states in YBCO exhibit charge density wave characteristics akin to high magnetic field effects, providing new insights into non-equilibrium superconducting states.

Findings

Photoinduced CDW resembles magnetic field-induced phenomena.

Broken pairing states lead to nucleation of 3D CDW correlations.

Photoinduced normal state shares features with equilibrium high-field states.

Abstract

The normal state of high-Tc cuprates has been considered one of the essential topics in high-temperature superconductivity research. However, compared to the high magnetic fields study of it, understanding a photoinduced normal state remains elusive. Here, we explore a photoinduced normal state of YBa$_2$Cu$_3$O$_{6.67}$ (YBCO) through a charge density wave (CDW) with time-resolved resonant soft x-ray scattering, as well as a high-magnetic field x-ray scattering. In the non-equilibrium state in which people predict a quenched superconducting state based on the previous optical spectroscopies, we experimentally observed a similar analogy to the competition between superconductivity and CDW shown in the equilibrium state. We further observe that the broken pairing states in the superconducting CuO$_2$ plane via the optical pump lead to nucleation of three-dimensional CDW precursor correlation, revealing that the photoinduced CDW is similar to phenomena shown under magnetic fields. Ultimately, these findings provide a critical clue that the characteristics of the photoinduced normal state show a solid resemblance to those under magnetic fields in equilibrium conditions.