Thermodynamic and Transport Study of Electron- and Hole-Doped MGa3 Single Crystals (M = Fe, Co)

• Published in: Journal of electronic materials Vol. 43; no. 6; pp. 1988 - 1992
• Main Authors: Cabrera-Baez, M., Magnavita, E. Thizay, Ribeiro, Raquel A., Avila, Marcos A.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Boston Springer US 01.06.2014; Springer
• Subjects: Applied sciences; Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Electronics; Electronics and Microelectronics; Exact sciences and technology; Instrumentation; Magnetic properties and materials; Materials Science; Methods of crystal growth; physics of crystal growth; Nanoscale materials and structures: fabrication and characterization; Optical and Electronic Materials; Other ferromagnetic metals and alloys; Physics; Quantum dots; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Solid State Physics; Studies of specific magnetic materials; Theory and models of crystal growth; physics of crystal growth, crystal morphology and orientation; Thermoelectric, pyroelectric devices, etc; quantum criticality; Carrier tuning; non-fermi liquids; Crystal growth; Quantum phase transition; Ground states; Doping; Ferromagnetic materials; Optimization; Thermoelectric properties; Specific heat; Thermoelectric materials; Non Fermi liquid; Thermoelectric power; Ferromagnetism; Magnetic properties; Band structure; Charge carriers; Semiconductor materials; Magnetization; Hole density; Quantum dots; Heat capacity; Thermoelectric devices; Indium additions; Monocrystals; Electronic structure; Growth mechanism; Structure modification
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-013-2932-1

FeGa 3 and related compounds have been subjects of recent investigation for their interesting thermoelectric, electronic, and magnetic behaviors. Here, single crystals of FeGa 3− y Ge y were grown by the self-flux technique with effective y  = 0, 0.09(1), 0.11(1), and 0.17(1) in order to investigate the evolution of the diamagnetic semiconducting compound FeGa 3 into a ferromagnetic metal, which occurs through the electron doping and band structure modifications that result from substitution of Ge for Ga. Heat capacity and magnetization measurements reveal non-Fermi liquid behavior in the vicinity of the transition from a paramagnetic to ferromagnetic ground state, suggesting the presence of a ferromagnetic quantum critical point (FMQCP). We also present the first results of hole doping in this system by the growth of FeGa 3− y Zn y single crystals, and electron- and hole doping of the related compound CoGa 3 by CoGa 3− y Ge y and CoGa 3− y Zn y crystal growths, aiming to search for further routes to band structure and charge carrier tuning, thermoelectric optimization, and quantum criticality in this family of compounds. The ability to tune the charge carrier type warrants further investigation of the MGa 3 system’s thermoelectric properties above room temperature.