Physics – Condensed Matter – Mesoscale and Nanoscale Physics
Scientific paper
2012-03-01
Physics
Condensed Matter
Mesoscale and Nanoscale Physics
Scientific paper
We have investigated the magnetic properties of carbon powders which consist of nanodisks, nanocones and a small fraction of carbon black particles. Magnetization measurements were carried out using a supercomputing quantum interface device (SQUID) in magnetic fields $-5<\mu_{0}H<5\:\mathrm{T}$ for temperature $2\leq T<350\:\mathrm{K}$. In the temperature range $2\leq T<10\:\mathrm{K}$, magnetization $M$ versus temperature shows an abrupt transition with a different behaviour than the Curie law. At $T=2\:\mathrm{K}$, magnetization $M$ versus magnetic field $\mu_{0}H$ shows a paramagnetic free spin behavior only in the case when $\mu_{0}H/T>1$T/K which could be a signature of electron localization in high magnetic fields at low temperature. Magnetization $M$ versus $T$ and $M$ versus $\mu_{0}H$ for these carbon powders show diamagnetism with an additional ferromagnetic contribution for temperature $2\leq T<350\:\mathrm{Only about 5% of the saturation magnetization could be assigned to a low level of Fe impurities (< 100 ppm). This ferromagnetic ordering is probably an intrinsic property of the carbon powder particles due to their layered structure containing both graphitic parts and disordered phases.
Cernak Jozef
Helgesen Geir
Kovác Jozef
Skjeltorp Arne T.
Voltr Josef
No associations
LandOfFree
Magnetic properties of carbon nanodisks and nanocones powder does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Magnetic properties of carbon nanodisks and nanocones powder, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnetic properties of carbon nanodisks and nanocones powder will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-165088