Generic phase diagram of "electron-doped" T' cuprates

TL;DR

This study reveals a revised phase diagram for electron-doped Nd2-xCexCuO4, showing a monotonic increase in Tc with decreasing doping, emphasizing the critical role of oxygen impurities in superconductivity and magnetism.

Contribution

The paper presents the first detailed phase diagram of oxygen-stoichiometric Nd2-xCexCuO4, highlighting the impact of oxygen impurities on its superconducting and magnetic properties.

Findings

Tc increases monotonically from 24 K to 29 K as x decreases from 0.15 to 0.00

Oxygen reduction treatment effectively removes interstitial Oap atoms

Results differ significantly from previous bulk phase diagrams

Abstract

We investigated the generic phase diagram of the electron doped superconductor, Nd2-xCexCuO4, using films prepared by metal organic decomposition. After careful oxygen reduction treatment to remove interstitial Oap atoms, we found that the Tc increases monotonically from 24 K to 29 K with decreasing x from 0.15 to 0.00, demonstrating a quite different phase diagram from the previous bulk one. The implication of our results is discussed on the basis of tremendous influence of Oap "impurities" on superconductivity and also magnetism in T' cuprates. Then we conclude that our result represents the generic phase diagram for oxygen-stoichiometric Nd2-xCexCuO4.