Title: Magnetic x-ray spectromicroscopy of the static and dynamic behavior of novel spin textures

Speaker: 
Peter Fischer
Institution: 
Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley CA, USA
Physics Department, University of California, Santa Cruz, CA, USA
Email: 
PJFischer@lbl.gov
Speaker Link: 
http://pjfischer.lbl.gov/public.htm
Date: 
Wednesday, May 3, 2017
Time: 
4:00 pm
Location: 
NS2 1201

Abstract:

Nanomagnetism research which aims to understand and control magnetic properties and behavior on the nanoscale through proximity and confinement, is currently shifting its focus to emerging phenomena occurring on mesoscopic scales. New avenues to control magnetic materials open up through enhanced complexity and new functionalities, which can impact the speed, size and energy efficiency of spin driven applications.  Magnetic soft X-ray spectro-microscopies [1] provide unique characterization opportunities to study the statics and dynamics of spin textures in magnetic materials combining X-ray magnetic circular dichroism (X-MCD) as element specific, quantifiable magnetic contrast mechanism with spatial and temporal resolutions down to fundamental magnetic length and time scales.

 

I will review recent achievements and future opportunities with magnetic x-ray spectro-microscopies, specifically with full-field soft X-ray transmission microscopy and soft x-ray ptychography. Whereas the former uses Fresnel zone plate optics to form an image, the latter retrieves high resolution amplitude and phase contrast images via reconstruction algorithms of oversampled diffraction patterns [2].  Examples will include the static properties and dynamic behavior of magnetic vortex [3,4] and skyrmion [5] textures with potential application to novel magnetic logic elements [6], magnetic x-ray spectromicroscopy of domain walls [7], and approaches to image the 3dim magnetic domain structures in rolled-up thin films with x-ray tomography [8].

 

DOWNLOAD BIO HERE

 

This work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, Contract No. DE-AC02-05-CH1123 in the Non-Equilibrium Magnetic Materials Program (MSMAG).

 

[1] P. Fischer and H. Ohldag, Report on Progress in Physics 78 094501 (2015)

[2] X. Shi et al, Appl Phys Letter 108, 094103 (2016)

[3] R. Streubel, et al. Appl Phys Lett 107 112406 (2015)

[4] M.-Y. Im, et al. Nature Communication 5 5620 (2014)

[5] S. Woo et al., Nature Materials 15 501 (2016)

[6] H. Jung, et al., ACS Nano 6 3712 (2012)

[7] M.J. Robertson, et al., J Appl Phys 117 17D145 (2015)

[8] R. Streubel, et al., J. Phys D: Appl Phys 49(36) (2016)

Host: 
Xiaoqing Pan