SCGSR student Brian Lejeune. Posted 4/25/2018
What is your major, year, where do you go to college?
I am a 5th year Ph.D. student at Northeastern University, Boston, Mass., majoring in chemical engineering.
2. Why did you get involved in the SCGSR grant program? (Brian's fellowship runs from January to July 2018.)
My dissertation titled Composition-Lattice Interactions in Intermetallic Ferromagnetic Systems has largely focused on the study of anisotropic properties in the ferromagnetic AlFe2B2 system. To date, the coupling between the crystal structure and magnetism within the orthorhombic layered crystal structure of AlFe2B2 has only been studied indirectly. The Basic Energy Science crystal growth priority research area of the Office of Science Graduate Student Research (SCGSR) fellowship is in alignment with the single crystal growth studies needed to expand the breadth and depth of knowledge within the AlFe2B2 system. This research supports my current dissertation objectives by contributing to the understanding of lattice-magnetism interactions in the AlFe2B2 material system.
3. Why did you choose Ames Laboratory or how did you find someone at Ames Laboratory to work with?
Prior to coming to the Ames Laboratory for my SCGSR award, I was supported through a one year collaborative ARPA-e Ideas grant between our Nanomagnetism group at Northeastern University led by Cabot Professor Laura H. Lewis and the Ames Laboratory led by Dr. Matthew Kramer to identify engineering parameters of the AlT2X2 system to evaluate its full potential as a magnetocaloric material. Based on the previous relationship with the Ames Laboratory, Dr. Kramer’s prior knowledge of the AlFe2B2 material system, and the single crystal growth expertise available, the Ames Laboratory was a perfect fit.
4. What have you been doing while here? What's the title of your research? How's it been going, e.g. successes, surprises, etc.?
My SCGSR fellowship entitled, “Probing Anisotropy in AT2B2 Layered Crystals” has gotten off to a good start over the past couple of months. I have mainly been focusing on learning about phase selection criteria and gaining a deeper understanding of the Al-Fe-B phase diagram, which is needed to optimize the growth conditions for single crystal synthesis. In addition, I have expanded my knowledge of crystal structure refinement techniques, which has proved useful in determining the phase constitution of AlFe2B2 samples and lattice distortions within the AlFe2B2 phase.
5. Does your goal for your SCGSR relationship at Ames Lab look accomplishable? If so, what will it have helped you do and what will you do with that knowledge when you go back to your graduate program?
At this point, I am optimistic that it will be possible to accomplish the goals of my project in growth and characterization of AlFe2B2 single crystals. Work that I have done since arriving at the Ames Laboratory on phase selection as well as more accurately mapping out the Al-Fe-B phase diagram has been instrumental in narrowing down the starting composition and growth conditions for single crystal synthesis.
6. Any comments about the effectiveness of doing your project at Ames Laboratory?
It has been truly a pleasure to be able to interact and learn on a daily basis from researchers of such high caliber at the Ames Laboratory. Additionally, the Lab’s resources for synthesis and characterization of materials are much more extensive than what is available at Northeastern University. These two factors have really helped to accelerate the progress of my research over the past couple of months.
7. How has the SCGSR program at Ames Laboratory affected you professionally, personally?
I would highly recommend the SCGSR program to any graduate student who is dedicated and has a clearly defined aspect of their dissertation they wish to investigate but may not have the resources to do the work at their home institution. In addition to allowing me to explore aspects of my dissertation, which I may have otherwise been unable to do, my SCGSR fellowship has allowed me to have a glimpse into the culture of working at a national lab, which I am interested in pursuing after graduation. Lastly, national labs are home to some of the leading researchers in the country and to be able to learn first-hand and expand my professional network to include researchers of that caliber is a privilege.
8. How has Brian been as a student, what do you think of the SCGSR fellowship program, and would you recommend it and look forward to working with more SCGSR students in the future? – Matthew Kramer, Director, Division of Materials Science and Engineering, Ames Laboratory.
It has been great having Brian; he is a motivated student. He has jumped into the research with both feet, making contacts with a number of the staff. He’s been learning from them and taking advantage of all the opportunities that the Lab has to offer in synthesis and characterization. This is a great program for a student who can really throw themselves into a project and tackle a very specific problem, in this case, the role of small chemical changes during processing resulting in different lattice sites decorations, which has changed the magneto-caloric response.