Abstract
Neutron measurements show that superconducting ( ) develops antiferromagnetic spin density wave magnetic order ( ), which squares up with decreasing temperature yielding a series of higher-order magnetic Bragg peaks with odd harmonics. Below where magnetization indicates a net moment develops, even-order Bragg peaks develop which low field ( ) polarized beam measurements show are magnetic in origin. The data directly demonstrate the existence of a net magnetization with a periodicity of , confirming the microscopic coexistence of spontaneous weak ferromagnetism with superconductivity.
- Received 27 March 2001
DOI:https://doi.org/10.1103/PhysRevLett.87.107001
©2001 American Physical Society