TY - GEN
T1 - Positive magnetisation in carbon nanoclusters produced by high-repetition-rate laser ablation
AU - Rode, Andrei V.
AU - Arcon, Denis
AU - Zorko, Andrej
AU - Jaglicic, Zvonko
AU - Christy, Andrew G.
AU - Madsen, Nathan R.
AU - Luther-Davies, Barry
AU - Lau, Desmond W.M.
AU - McCulloch, Dougal G.
PY - 2007
Y1 - 2007
N2 - Carbon nanoclusters produced by high-repetition-rate laser ablation of graphite and glassy carbon in Ar exhibits para- and ferromagnetic behaviour at low temperature. The results show that the degree of remanent order is strongly dependent on the magnetic history, i.e. whether the samples were cooled under zero-field or field conditions. Such behaviour is typical for a spin glass structure where the system can exist in many different roughly equivalent spin configurations. The spin-freezing temperature is unusually high (50 - 300 K) compared with ≤ 15 K for typical spin glasses. The maximum in the zero-field magnetic susceptibility experiments and their field dependence indicate that there is competition between ferromagnetic and antiferromagnetic exchange pathways, accounting for the spin glass behavior and/or a low-dimensionality of the system.
AB - Carbon nanoclusters produced by high-repetition-rate laser ablation of graphite and glassy carbon in Ar exhibits para- and ferromagnetic behaviour at low temperature. The results show that the degree of remanent order is strongly dependent on the magnetic history, i.e. whether the samples were cooled under zero-field or field conditions. Such behaviour is typical for a spin glass structure where the system can exist in many different roughly equivalent spin configurations. The spin-freezing temperature is unusually high (50 - 300 K) compared with ≤ 15 K for typical spin glasses. The maximum in the zero-field magnetic susceptibility experiments and their field dependence indicate that there is competition between ferromagnetic and antiferromagnetic exchange pathways, accounting for the spin glass behavior and/or a low-dimensionality of the system.
UR - http://www.scopus.com/inward/record.url?scp=70349907073&partnerID=8YFLogxK
U2 - 10.1557/proc-998-j03-05
DO - 10.1557/proc-998-j03-05
M3 - Conference contribution
AN - SCOPUS:70349907073
SN - 9781605604312
T3 - Materials Research Society Symposium Proceedings
SP - 50
EP - 56
BT - Materials Research Society Symposium Proceedings - Nanoscale Magnetics and Device Applications
PB - Materials Research Society
T2 - Nanoscale Magnetics and Device Applications - 2007 MRS Spring Meeting
Y2 - 9 April 2007 through 13 April 2007
ER -