One of the major application of FePt nanoparticles is in the high energy exchange coupled nanocomposite magnets. Dr Hao Zeng's published his paper on enhancement of energy product by 50 % by mixing hard(FePt) and soft(Fe3O4) nanoparticles in Nature. To achieve maximum exchange coupling, the soft material should be coated on hard materials or vice versa to maintain the 100 % possibility of contact between these two. His another paper on coreshell particle inspired me to continue this work.
The biggest problem with as synthesized nanoparticles is that they are superparamagnetic. To convert them into ferromagnetic, they have to be annealed above 600 C but annealing can cause the agglomeration of these nanoparticles. Several groups tried a lot of methods to overcome this problem but no could solve this completely. Alabama group tried to decrease the fcc-fct transition temperature by doping Au, Ag and Cu while Japanese group was successful to produce monolayer of fct nanoparticles by using polymers. Some groups tried to make direct partially fct nanoparticles in synthesis by using high boiling point solvent. I am proud to say that we are the first one to produce the monodisperse fct FePt nanoparticles in world. We got the main breakthrough in our research when our work on fct nanoparticles was mentioned by Nanotech-now, physics web, nanotechweb, iran-daily, physicsnews, nanotech-now and several other medias. We successfully synthesized monodisperse fct FePt nanoparticles (without any sintering) first time ever by our salt matrix annealing and published those results in JPD.
Now we have so many things to explore. First and the most obvious thing is alignment of this smallest premanent magnets. These particles are anisotropic and can be aligned if put in the magnetic field which will increase their magnetic properties by four times. But the biggest problem we are having is to keep them seperate. Unlike fcc nanoparticles, these particles do not have any coating as all the surfactant decompose during annealing and becuase of that these tiny magnets come together due to their obvious magnetic force. Few groups coated the fcc FePt nanoparticles with SiO2 shell and them anneal them to convert them into fct while Silica shell kept them seperate. ALabama group showed a llittle alignment from their direct partially fct nanoparticles from high boiling point solvent. Even they didn't show clear alignment. So the war is going on and several groups in the world are working to achieve the alignment of FePt nanoparticles. We hope that we'll win this war also.
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Charles Lieber in Harvard.
George M. Whitesides in Harvard.
Chad Mirkin in Northwestern.
Peidong Yang in U C Berkely.
Z. L. Wang in Gatech.
Shouheng Sun in Brown.
Vinyak Dravid in Northwestern
(ex-student of my supervisor in IITB).
Brian Korgel in U T Austin.
Hong Yang in Rochester.
Y. Xia in U Washington.
David Laughlin in CMU.
Paul Alivisatos in UCB.
D J Sellmyer in U Nebraska Lincoln.
Michael S Wong in Rice.
Vicky Colvin in Rice.
Sara Majetich in CMU.
T. Hyeon in SNU, S. Korea.
Kannan M. Krishnan in U Washington.
G. M. Chow in NUS, Singapore.
Y. Qiang in U Idaho.
Stephen O Brien in Columbia. (video)
(his post doc E. V. Shevchenko)
Shan X Wang in Stanford.
Nian Sun in Northeastern.
31.85
13.53
9.16
8.44
7.21
6.9
5.67
4.3
4.1
3.83
3.32
3.29
2.72
3.17
2.25
1.64
1.03
0.84
Science
Nature Meterials
Ang. Chem. Int. Ed.
Nanoletters
PRB
JACS
Adv. Materials
APL
Chem Matl.
JPC B
Nanotechnology
Langmuir
J. Mat. Chem.
IEEE T Nano
JAP
JPD
JMMM
IEEE T Mag
one of the top research scientist of India)
M. El Sayed in Gatech.
K. S. Suslick in UIUC.
George Thompson in U Alabama.
D. E. Nikles in U Alabama.
J. W. Harrell in U Alabama.
X. Peng in U Arkansas.
Clemens Burda in Case Western.
Y. Ping Sun in Clemson. (old site)
A. Wei in Purdue.
U. Wiesner in Cornell.
Vinod Labheshwar in U Neb Med. Cent.
Michael Giersig in CAESER, Germany.
J Cheon in Yonsei University, Korea. (excellent Nano-links)
Marry P. Pileni in CNRS, France.
Do Kyung Kim in Keele Univ, UK.
Challa Kumar in CAMD, LSU.
Raymond E. Schaak in Texas A&M.
Carolina Ross in MIT.
Angela Belcher in MIT.
Murali Sastry in NCL, Pune, India.
(excellent research & publications)
Govardhan Mehta (ex director of IISc).
Peter Schiffer in PennState.
Sam Liu in Dayton.
Hong you Fan in Univ New Mexico.
Prof Ajayan in RPI
Prof Zhang at Gatech.
Some pics of University of rochester also.
Top 20 grad school (materials engineering) in USA.
Cost of living in major cities in US.
Check what CBS told about IIT.
References.
Magnetic
Materials
Brookhaven.
Argonne.
Naval Research.
Stanford.
NIST (MD)
IBM Almaden.
UCSD.
Alabama.
Nebraska Lincoln.
MRSEC at UNL.
U Houston.
Minnesota.
North Eastern.
Utah.
York, UK
Hitachi.
Arnold.
ACS,
AIP,
IOP,
RSC,
Wiley,
Springerlink,
Crossref,
Sciencedirect,
IEEE magnetics.
Webofscience.
Hard Drives bumping against physical limits.
MRAM - Universal Memory ( Still a dream )
MRAM site, Definition on wikipedia, CNET and geeks and ESM.
Introduction of quantum dots.
Lab DeMo - Synthesis of CdSe quantum dots - Simple and Clear.
Scale up of Q dots.
Nano goes into Lingo - Apple Ipod Nano
What's inside IPOD Nano
Nanofactory based on molecular nanotechnology
Some research videos from Northwestern Materials Science.
Some info on recording media.
Nice presentations on Nanotechnology.
India's first commercial Nano Venture
India think about Nanotechnology
India Needs More PhDs, here's why
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