Magnetic order of intermetallic FeGa${}_{3-y}$Ge${}_y$ studied by $\mu$SR and ${}^{57}$Fe Mössbauer spectroscopy

Abstract

Temperature dependent magnetization, muon spin rotation and ${}^{57}$Fe Mössbauer spectroscopy experiments performed on crystals of intermetallic FeGa${}_{3-y}$Ge${}_y$ ($y=0.11,0.14,0.17,0.22,0.27$, $0.29,0.32$) are reported. Whereas at $y=0.11$ even a sensitive magnetic microprobe such as $\mu$SR does not detect magnetism, all other samples display weak ferromagnetism with a magnetic moment of up to 0.22 ${\mu }_B$ per Fe atom. As a function of doping and of temperature a crossover from short range to long range magnetic order is observed, characterized by a broadly distributed spontaneous internal field. However, the $y=0.14$ and $y=0.17$ remain in the short range ordered state down to the lowest investigated temperature. The transition from short range to long range order appears to be accompanied by a change of the character of the spin fluctuations, which exhibit spin wave excitations signature in the LRO part of the phase diagram. Mössbauer spectroscopy for $y=0.27$ and 0.32 indicates that the internal field lies in the plane perpendicular to the crystallographic $c$ axis. The field distribution and its evolution with doping suggest that the details of the Fe magnetic moment formation and the consequent magnetic state are determined not only by the dopant concentration but also by the way the replacement of the Ga atoms surrounding the Fe is accomplished.

References in corpus (11)

• Complexity in Strongly Correlated Electronic Systems
• Ferromagnetic Instability in a Doped Band-Gap Semiconductor FeGa${}_3$
• Interplay between localized and itinerant magnetism in Co substituted FeGa${}_3$
• Effect of Chemical Doping on the Thermoelectric Properties of FeGa3
• Electronic correlations in FeGa${}_3$ and the effect of hole doping on its magnetic properties
• Itinerant origin of the ferromagnetic quantum critical point in Fe(Ga,Ge)3
• Towards ferromagnetic quantum criticality in FeGa3-xGex: 71Ga NQR as a zero field microscopic probe
• Magnetic order and spin dynamics in the proximity of a ferromagnetic quantum critical point: A μSR study of YbNi4P2
• Emergence of competing magnetic interactions induced by Ge doping in the semiconductor FeGa3
• Probing the magnetic phases in the Ni-V alloy close to the disordered ferromagnetic quantum critical point with muSR
• Structural and electronic properties of Fe(AlxGa1-x)3 system

Cited by in corpus (1)

• Spin dynamics of FeGa${}_{3-x}$Ge${}_x$ studied by Electron Spin Resonance