TY - JOUR
T1 - Contrasting effect of la substitution on the magnetic moment direction in the Kondo semiconductors CeT2 Al10 (T=Ru,Os)
AU - Adroja, D. T.
AU - Hillier, A. D.
AU - Ritter, C.
AU - Bhattacharyya, A.
AU - Khalyavin, D. D.
AU - Strydom, A. M.
AU - Peratheepan, P.
AU - Fåk, B.
AU - Koza, M. M.
AU - Kawabata, J.
AU - Yamada, Y.
AU - Okada, Y.
AU - Muro, Y.
AU - Takabatake, T.
AU - Taylor, J. W.
N1 - Publisher Copyright:
© 2015 American Physical Society.
PY - 2015/9/14
Y1 - 2015/9/14
N2 - The opening of a spin gap in the orthorhombic compounds CeT2Al10 (T=RuandOs) is followed by antiferromagnetic ordering at TN=27 and 28.5 K, respectively, with a small ordered moment (0.29-0.34μB) along the c axis, which is not an easy axis of the crystal field (CEF). In order to investigate how the moment direction and the spin gap energy change with La doping in Ce1-xLaxT2Al10 (T = Ru and Os) and also to understand the microscopic nature of the magnetic ground state, we here report on magnetic, transport, and thermal properties, neutron diffraction (ND), and inelastic neutron scattering (INS) investigations on these compounds. Our INS study reveals the persistence of spin gaps of 7 and 10 meV in the 10% La-doped T = Ru and Os compounds, respectively. More interestingly our ND study shows a very small ordered moment of 0.18 μB along the b axis in Ce0.9La0.1Ru2Al10, however a moment of 0.23 μB still along the c axis in Ce0.9La0.1Os2Al10. This contrasting behavior can be explained by a different degree of hybridization in CeRu2Al10 and CeOs2Al10, being stronger in the latter than in the former. Muon spin rotation (μSR) studies on Ce1-xLaxRu2Al10 (x=0, 0.3, 0.5, and 0.7), reveal the presence of coherent frequency oscillations indicating a long-range magnetically ordered ground state for x=0 to 0.5, but an almost temperature independent Kubo-Toyabe response between 45 mK and 4 K for x=0.7. We compare the results of the present investigations with those reported on the electron and hole doping in CeT2Al10.
AB - The opening of a spin gap in the orthorhombic compounds CeT2Al10 (T=RuandOs) is followed by antiferromagnetic ordering at TN=27 and 28.5 K, respectively, with a small ordered moment (0.29-0.34μB) along the c axis, which is not an easy axis of the crystal field (CEF). In order to investigate how the moment direction and the spin gap energy change with La doping in Ce1-xLaxT2Al10 (T = Ru and Os) and also to understand the microscopic nature of the magnetic ground state, we here report on magnetic, transport, and thermal properties, neutron diffraction (ND), and inelastic neutron scattering (INS) investigations on these compounds. Our INS study reveals the persistence of spin gaps of 7 and 10 meV in the 10% La-doped T = Ru and Os compounds, respectively. More interestingly our ND study shows a very small ordered moment of 0.18 μB along the b axis in Ce0.9La0.1Ru2Al10, however a moment of 0.23 μB still along the c axis in Ce0.9La0.1Os2Al10. This contrasting behavior can be explained by a different degree of hybridization in CeRu2Al10 and CeOs2Al10, being stronger in the latter than in the former. Muon spin rotation (μSR) studies on Ce1-xLaxRu2Al10 (x=0, 0.3, 0.5, and 0.7), reveal the presence of coherent frequency oscillations indicating a long-range magnetically ordered ground state for x=0 to 0.5, but an almost temperature independent Kubo-Toyabe response between 45 mK and 4 K for x=0.7. We compare the results of the present investigations with those reported on the electron and hole doping in CeT2Al10.
UR - http://www.scopus.com/inward/record.url?scp=84942437123&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.92.094425
DO - 10.1103/PhysRevB.92.094425
M3 - Article
AN - SCOPUS:84942437123
SN - 1098-0121
VL - 92
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 9
M1 - 094425
ER -