Magnetic order of rare-earth tritelluride CeTe3 at low temperature

Rare-earth tritelluride CeTe3, which belongs to the family of quasi-two dimensional compounds RTe3 (where R = Y, La-Sm, Gd-Tm), has highly two-dimensional crystal structure. Fermi surfaces consist of inner and outer square sheets, large regions of which are nested by a single incommensurate wave-vector. Because of the characteristic quasi-two-dimensional nature of square Fermi surfaces, the charge density wave of RTe3 is formed with an extremely large gap and extensively investigated. Despite the extensive studies on the charge density wave in recent years, remarkably little is known about magnetism and low-temperature properties of CeTe3. We have investigated the low-temperature magnetic-ordered-phases of the rare-earth tritelluride CeTe3 with single crystals. We measured specific heat, electrical resistivity and differential magnetic susceptibility using a 3He cryostat down to about 0.45 K and a 3He/4He dilution refrigerator down to 0.1 K. We have found that heavy quasi-particles form spin density wave at low temperatures, reflecting the square Fermi surfaces with the quasi-one-dimensional nature.