Prof. Nian X. Sun
Electrical and Computer Engineering Department, Northeastern University, Boston, MA, USA
Web: www.neu.edu/sunlab; Phone: +1 (617) 373-3351 Email: 该邮件地址已受到反垃圾邮件插件保护。要显示它需要在浏览器中启用 JavaScript。

时间：2014年8月22日下午2：30
地点：唐仲英楼A213会议室

The coexistence of electric polarization and magnetization in multiferroic materials provides great opportunities for realizing magnetoelectric coupling, including electric field control of magnetism, or vice versa, through a strain mediated magnetoelectric interaction effect in layered magnetic/ferroelectric multiferroic heterostructures [1-7]. Strong magnetoelectric coupling has been the enabling factor for different multiferroic devices, which however has been elusive, particularly at RF/microwave frequencies. In this presentation, I will cover the most recent progress on new integrated GHz magnetic inductors based on solenoid structures with FeGaB/Al2O3 and FeCoB/Al2O3 multilayer films, which show significantly enhanced inductance and quality factor at GHz frequencies over their air core counterparts. These inductors show excellent high-frequency performance with a wide operation frequency range of 0.5-2.5GHz, in which the inductance is flat and the inductance of the magnetic inductor shows >150% enhancement compared with that of the same size air core inductor and enhanced quality factor of close to 20. By putting these inductors on a piezoelectric slab and applying DC voltage, power efficient voltage tunable inductors with inductance tunability of 50%~150% are achieved. These novel voltage tunable GHz inductors show great promise for applications in radio frequency integrated circuits. At the same time, we will demonstrate other voltage tunable multiferroic devices, including ultra-sensitive nanoelectromechanical systems magnetoelectric sensors with picoTesla sensitivity [5], multiferroic voltage tunable bandpass filters [6], tunable bandstop filters, tunable phase shifters and spintronics, etc.

1. N.X. Sun and G. Srinivasan, SPIN, 02, 1240004 (2012);
2. J. Lou, et al., Advanced Materials, 21, 4711 (2009);
3. J. Lou, et al. Appl. Phys. Lett. 94, 112508 (2009);
4. M. Liu, et al. Advanced Functional Materials, 21, 2593 (2011);
5. T. Nan, et al. Scientific Reports, 3, 1985 (2013);
6. M. Liu, et al. Advanced Materials, 25, 1435 (2013);
7 M. Liu, et al. Advanced Functional Materials, 19, 1826 (2009).

Short Bio: Nian Sun is a professor at the Electrical and Computer Engineering Department, Northeastern University. He received his Ph.D. degree from Stanford University. Prior to joining Northeastern University, he was a Scientist at IBM and Hitachi Global Storage Technologies. Dr. Sun was the recipient of the NSF CAREER Award, ONR Young Investigator Award, the Søren Buus Outstanding Research Award, etc. His research interests include novel magnetic, ferroelectric and multiferroic materials, devices and subsystems. He has over 150 publications and over 20 patents and patent disclosures. One of his papers was selected as the "ten most outstanding full papers in the past decade (2001~2010) in Advanced Functional Materials". Dr. Sun has given over 80 invited or keynote presentations in national and international conferences and universities. He is an editor of IEEE Transactions on Magnetics, and a fellow of the Institute of Physics, and of the Institution of Engineering and Technology.