Tag: Materials

Professor John Jaszczak (Physics), adjunct curator at the A. E. Seaman Mineral Museum, published a paper in the September/October issue of The Mineralogical Record, “Spectacular Sulfides from the Merelani Tanzanite Deposit, Manyara Region, Tanzania.” The paper’s coauthors are Simon Harrison, Mike Keim, Mike Rumsey (Natural History Museum, London) and Michael Wise (Smithsonian Institution).

Vol. 45, No. 5 September – October 2014

From Tech Today.

Fluorinated boron nitride nanotube as an ideal spin filter

Advisor: Dr. Ranjit Pati

Understanding the electronic structure and the transport property of nano scale materials is of fundamental importance, since these materials are the ultimate candidates for the future of nano technology. Several nano materials, such as quantum dots, semiconducting nano-wires, and organic molecules, have been explored both theoretically and experimentally as the components of electronic circuitry over the last two decades. Among several interesting nano materials, metal free magnetic nano materials are found to be very enticing due to the presence of magnetism in the absence of magnetic ions. Traditionally, the magnetism comes from partially occupied d and f states in the materials; however, this understanding is not always true since s and p states are found to contribute to the magnetism in the metal free magnetic materials. The main advantage of these materials is their high Curie temperature; as a result, they can be utilized in room temperature spin-electronics (spintronics). Recently, using a first-principles approach, we have demonstrated that the fluorinated boron nitride nanotube (BNNT), which is a metal-free magnetic entity, can be used as an excellent spin filter. All majority spin carriers are almost completely blocked while passing through the fluorinated BNNT channel, allowing only the minority spin carriers to pass. We have shown that the long range ferromagnetic spin ordering in fluorinated BNNTs occurs at a temperature much above room temperature.

For more information, please visit my webpage: http://www.phy.mtu.edu/~kbdhunga

By Kamal B. Dhungana

Reference:

Kamal B. Dhungana, Ranjit Pati, Fluorinated Boron Nitride Nanotube Quantum Dots: A Spin Filter. J. Am. Chem. Soc., 2014, 136, 11494–11498. 

Professor John A. Jaszczak (Physics) co-authored a paper in the journal Carbon [vol 76, Sept. 2014, but available on line now], “Plasma synthesis of hexagonal-pyramidal graphite hillocks.” First-author X. Glad and other co-authors are from Universite’ de Lorraine and CNRS (France).

http://dx.doi.org/10.1016/j.carbon.2014.04.084

From Tech Today.