In the past years, magnetism-driven ferroelectricity and gigantic magnetoelectric effects have been reported for a number of frustrated magnets with spiral magnetic orders. Such materials are of high current interest due to their potential for spintronics and low-power magnetoelectric devices. However, their low magnetic order temperatures (typically <100K) greatly restrict their fields of application. Here we demonstrate that the stability domain of the spiral phase in the perovskite YBaCuFeO5 can be enlarged by more than 150K through a controlled manipulation of the Fe/Cu chemical disorder. Moreover we show that this novel mechanism can stabilize the magnetic spiral state of YBaCuFeO5 above the symbolic value of 25{\deg}C at zero magnetic field. Our findings demonstrate that the properties of a magnetic spiral, including its wavelength and stability range, can be engineered through the control of chemical disorder, offering a great potential for the design of materials with magnetoelectric properties beyond room temperature.
@article{arxiv.1608.03372,
title = {Tuning magnetic spirals beyond room temperature with chemical disorder},
author = {Mickaël Morin and Emmanuel Canévet and Adrien Raynaud and Marek Bartkowiak and Denis Sheptyakov and Voraksmy Ban and Michel Kenzelmann and Ekaterina Pomjakushina and Kazimierz Conder and Marisa Medarde},
journal= {arXiv preprint arXiv:1608.03372},
year = {2017}
}