Two stages of Kondo effect and competition between RKKY and Kondo in Gd-based intermetallic compound

✍ Scribed by Mehdi Vaezzadeh; Ahmad Yazdani; Majid Vaezzadeh; Gissoo Daneshmand; Ali Kanzeghi

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 96 KB
• Volume: 378-380
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2006.01.546

✦ Synopsis

The magnetic behavior of Gd-based intermetallic compound (Gd 2 Al ð1ÀxÞ Au x ) in the form of the powder and needle, is investigated. All the samples are an orthorhombic crystal structure. Only the compound with x ¼ 0:4 shows the Kondo effect (other compounds have a normal behavior). Although, for the compound in the form of powder, with x ¼ 0:4, the susceptibility measurement wðTÞ shows two different stages. Moreover for ðT4T K2 Þ a fall of the value of wðTÞ is observable, which indicates a weak presence of ferromagnetic phase. About the two stages of Kondo effect, we observe at the first (T K1 ) an increase of wðTÞ and in the second stage (T K2 ) a new remarkable decrease of wðTÞ, ðT K1 4T K2 Þ. For the sample in the form of needles, the first stage is observable only under high magnetic field. This first stage could be corresponds to a narrow resonance between Kondo cloud and itinerant electron. The second stage, which is remarkably visible for the sample in the form of the powder, can be attribute to a complete polarization of Kondo cloud. Observation of these two Kondo stages could be due to the weak presence of RKKY contribution.