|Back to calendar|
|Title:||ALS-CXRO Seminar Series | Denys Makarov (IFW Dresden/Germany)|
|When:||10/ 2/2013 3:00 PM - 4:00 PM|
|Description:||ALS/CXRO Seminar Series|
Wed, Oct 2, 2013
15-253 Conf Rm
Magnetism in curved surfaces
Flexible, stretchable, and printable electronics is a dynamically developing research area with already a variety of commercially available devices. Shapeable electronics and optoelectronics have been developed already for a few years . Very recently, we added a new member to this family – the shapeable (stretchable [2,3] and printable ) magnetoelectronics. This development paves the way towards a unique class of devices with important functionality being not only stretchable and fast, but also with the ability to react and respond to a magnetic field.
We successfully fabricated layered magnetic structures revealing a giant magnetoresistance (GMR) effect [2,3] on free-standing elastic Poly(dimethylsiloxane) (PDMS) membranes. The performance of GMR sensors on rigid silicon and on free-standing PDMS is similar and does not change with tensile deformations of up to 29% revealing a top sensitivity of 0.8 %/Oe . These highly stretchable and highly sensitive elements are demanded for novel application fields like smart skin and flexible and stretchable consumer electronics equipped with magnetic functionalities.
The boost of progress in the fabrication of those shapeable magnetic nanomembranes has triggered the interest in fundamental aspects of magnetism in curved geometries [5,6]. Recent advances in nanofabrication allowed us to realize the first artificial complex helimagnetic-like configurations, namely hollow-bar-, corkscrew-, and radial-magnetized 3D micro-helix coils . From a theoretical point of view, radial magnetized architectures like Swiss roll structures  lack inversion- as well as time-reversal symmetry and are therefore characterized by a ferro-toroidic order. The induction of a finite toroidal moment by nanofabrication techniques could lead to new insights on this elusive type of long-range order and it’s intimately role in mutiferroic behavior.
In this talk, I will review the recent advances in the field of curved magnetic nanomembranes and emergent applications of this novel technology.
 J.A. Rogers et al., Nature 477, 45 (2011).
 M. Melzer et al., Nano Lett. 11, 2522 (2011).
 M. Melzer et al., Adv. Mater. 24, 6468 (2012).
 D. Karnaushenko et al., Adv. Mater. 24, 4518 (2012).
 R. Streubel et al., Nano Lett., 12, 3961 (2012).
 E. J. Smith et al., Phys. Rev. Lett., 107, 097204 (2011).
 E. J. Smith et al, Soft Matter 7, 11309 (2011).