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Confusing —Preceding unsigned comment added by (talk) 07:05, 27 October 2008 (UTC)

thermal fluctuations[edit]

The phrase "thermal fluctuations" is linked to a page on Temperature, which does not discuss thermal fluctuations. RockMagnetist (talk) 21:12, 26 August 2010 (UTC)

Hmm, the link could point to Boltzmann distribution or statistical mechanics or statistical fluctuations. None is quite perfect. Eventually I think thermal fluctuations deserves its own article, I would write it if I had time... --Steve (talk) 03:36, 27 August 2010 (UTC)
Interesting - I see that fluctuations is listed as a topic in statistical mechanics, but there is no link as yet. RockMagnetist (talk) 15:36, 17 September 2010 (UTC)
I decided to create the thermal fluctuations page. It's very skimpy at the moment, but it's needed.RockMagnetist (talk) 22:27, 17 September 2010 (UTC)
Good job! Now maybe there should be a link from temperature to thermal fluctuations... --Edgar.bonet (talk) 13:53, 18 September 2010 (UTC)
Thanks. Maybe a link should be added, but I'm not sure where exactly. Possibly in zeroth law of thermodynamics. --RockMagnetist (talk) 18:05, 28 September 2010 (UTC)
Not sure either. Maybe in Temperature#Overview, close to the mention of Brownian motion. Oh! You already linked Brownian motion to thermal fluctuations. Good!--Edgar.bonet (talk) 19:54, 30 September 2010 (UTC)

Interesting reference[edit]

I just found this interesting “topical review”:

Superparamagnetism, Subhankar Bedanta and Wolfgang Kleemann, J. Phys. D 42, 013001 (2009).

It’s a 28 pages long review article with 171 references and 31 citations. I still did not have time to go through it, but it looks like it may be a good reference for this Wikipedia article.
--Edgar.bonet (talk) 08:11, 20 September 2010 (UTC)

Thanks for pointing out this reference. I'll be interested to see what they say. --RockMagnetist (talk) 18:16, 28 September 2010 (UTC)

Split discussion[edit]

I suggest that the material on Neel relaxation be made into a separate article. It is the basis of so many subjects besides superparamagnetism - for example, it can be used to calculate the lower size limit for single-domain particles, and with a magnetic field it is the basis for thermoremanent magnetization. Two other choices for title would be Neel-Arrhenius relaxation or Neel-Brown relaxation, but I think the simpler choice is best. --RockMagnetist (talk) 18:30, 28 September 2010 (UTC)

I don't get the lower size limit for single-domain particles. Superparamagnetic particles are single domain. As for the thermoremanent magnetization, it looks to me as being all about the superparamagnetic/blocked transition... --Edgar.bonet (talk) 20:05, 30 September 2010 (UTC)
I often use "single-domain" to mean stable single-domain. The lower limit is then the size at which the blocking temperature is room temperature. As for thermoremanent magnetization, the SP/blocked transition is the starting point (at least for single-domain particles), but a lot of the applications would not belong on a superparamagnetism page. The stuff about time-dependent susceptibility is also, in my opinion, somewhere between stable single-domain and SP. There are many other applications of the Neel theory, magnetic viscosity being one example. --RockMagnetist (talk) 20:14, 30 September 2010 (UTC)