TY - JOUR
T1 - Effect of molybdenum 4d hole substitution in BaFe 2As 2
AU - Sefat, Athena S.
AU - Marty, Karol
AU - Christianson, Andrew D.
AU - Saparov, Bayrammurad
AU - McGuire, Michael A.
AU - Lumsden, Mark D.
AU - Tian, Wei
AU - Sales, Brian C.
PY - 2012/1/3
Y1 - 2012/1/3
N2 - We investigate the thermodynamic and transport properties of molybdenum-doped BaFe 2As 2 (122) crystals, the first report of hole doping using a 4d element. The chemical substitution of Mo in place of Fe is possible up to ∼ 7%. For Ba(Fe 1-xMo x) 2As 2, the suppression rate of the magnetic transition temperature with x is the same as in 3d Cr-doped 122 and is independent of the unit cell changes. This illustrates that the temperature-composition phase diagram for hole-doped 122 can be simply parameterized by x, similar to the electron-doped 122 systems found in the literature. Compared to 122 with a coupled antiferromagnetic order (T N) and orthorhombic structural transition (T 0) at 132 K, 1.3% Mo-doped 122 (x=0.013) gives T N=T 0=125(1) K according to neutron diffraction results and features in specific heat, magnetic susceptibility, and electrical resistivity. The cell volume expands by ∼1% with maximum Mo doping and T N is reduced to 90 K. There is a T * feature that is identified for lightly Cr- or Mo-doped 122 crystals, which is x dependent. This low-temperature transition may be a trace of superconductivity.
AB - We investigate the thermodynamic and transport properties of molybdenum-doped BaFe 2As 2 (122) crystals, the first report of hole doping using a 4d element. The chemical substitution of Mo in place of Fe is possible up to ∼ 7%. For Ba(Fe 1-xMo x) 2As 2, the suppression rate of the magnetic transition temperature with x is the same as in 3d Cr-doped 122 and is independent of the unit cell changes. This illustrates that the temperature-composition phase diagram for hole-doped 122 can be simply parameterized by x, similar to the electron-doped 122 systems found in the literature. Compared to 122 with a coupled antiferromagnetic order (T N) and orthorhombic structural transition (T 0) at 132 K, 1.3% Mo-doped 122 (x=0.013) gives T N=T 0=125(1) K according to neutron diffraction results and features in specific heat, magnetic susceptibility, and electrical resistivity. The cell volume expands by ∼1% with maximum Mo doping and T N is reduced to 90 K. There is a T * feature that is identified for lightly Cr- or Mo-doped 122 crystals, which is x dependent. This low-temperature transition may be a trace of superconductivity.
UR - http://www.scopus.com/inward/record.url?scp=84856507881&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.85.024503
DO - 10.1103/PhysRevB.85.024503
M3 - Article
AN - SCOPUS:84856507881
SN - 1098-0121
VL - 85
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 2
M1 - 024503
ER -