Investigation of the magnetic structure of holmium by the muonic method

The possibility of investigating by the muonic method spin-incommensurate helicoidal structures of rare-earth magnets is examined for the example of holmium. It is shown that at temperatures 20 K precession frequency of the muon spin is observed in holmium; this is characteristic for a simple helicoidal structure. The broadening of the frequency spectrum increases sharply at temperatures T⩽20 K, possibly as a result of the appearance of spin-slip structure at these temperatures. The Fermi contact magnetic field of the conduction electrons of holmium at a muon is measured.