Electrical resistivity of the μ-Al4Mn giant-unit-cell complex metallic alloy

• Published in: Philosophical magazine (2003. Print) 2011-07, Vol.91 (19-21), p.2756-2764
• Main Authors: Wencka†, M., Jazbec, S., Jagličić, Z., Vrtnik, S., Feuerbacher, M., Heggen, M., Roitsch, S., Dolinšek, J.
• Format: Article
• Language: English
• Subjects: Al-Mn system; complex metallic alloy; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electrical and thermal conduction in crystalline metals and alloys; electrical resistivity; Electronic conduction in metals and alloys; Electronic transport in condensed matter; Exact sciences and technology; Magnetic properties and materials; magnetic susceptibility; Magnetically ordered materials: other intrinsic properties; Physics; Saturation moments and magnetic susceptibilities; spin glass
• ISSN: 1478-6435; 1478-6443
• DOI: 10.1080/14786435.2010.512578

The μ-Al 4 Mn complex intermetallic phase with 563 atoms in its giant unit cell exhibits a complicated temperature dependence of electrical resistivity that has a broad maximum at about 175 K and a minimum at 13 K. The temperature dependence of the resistivity was reproduced by employing the theory of quantum transport of slow charge carriers, which predicts a crossover from the metallic (Boltzmann-type) positive-temperature-coefficient electrical resistivity at low temperatures to the insulator-like (non-Boltzmann) negative-temperature-coefficient resistivity at elevated temperatures. The low-temperature resistivity minimum was reproduced by considering it as a magnetic effect due to increased scattering of the conduction electrons by the Mn spins on approaching the spin glass phase that develops below the spin freezing temperature T f = 2.7 K.