Magnetic-field-induced charge-stripe order in the high temperature superconductor YBa2Cu3Oy

TL;DR

This study reveals that high magnetic fields induce charge stripe order in YBa2Cu3Oy, a high-temperature superconductor, providing insight into the competition between charge order and superconductivity.

Contribution

The paper demonstrates that magnetic fields can induce charge order in YBa2Cu3Oy, showing that charge ordering is an intrinsic property of cuprate superconductors.

Findings

Magnetic fields induce charge order without spin order in YBa2Cu3Oy.

Charge order develops when superconductivity diminishes.

Charge order occurs near 1/8 hole doping, similar to stripe-ordered cuprates.

Abstract

Electronic charges introduced in copper-oxide planes generate high-transition temperature superconductivity but, under special circumstances, they can also order into filaments called stripes. Whether an underlying tendency of charges to order is present in all cuprates and whether this has any relationship with superconductivity are, however, two highly controversial issues. In order to uncover underlying electronic orders, magnetic fields strong enough to destabilise superconductivity can be used. Such experiments, including quantum oscillations in YBa2Cu3Oy (a notoriously clean cuprate where charge order is not observed) have suggested that superconductivity competes with spin, rather than charge, order. Here, using nuclear magnetic resonance, we demonstrate that high magnetic fields actually induce charge order, without spin order, in the CuO2 planes of YBa2Cu3Oy. The observed static, unidirectional, modulation of the charge density breaks translational symmetry, thus explaining quantum oscillation results, and we argue that it is most likely the same 4a-periodic modulation as in stripe-ordered cuprates. The discovery that it develops only when superconductivity fades away and near the same 1/8th hole doping as in La2-xBaxCuO4 suggests that charge order, although visibly pinned by CuO chains in YBa2Cu3Oy, is an intrinsic propensity of the superconducting planes of high Tc cuprates.