School of Physical, Environmental and Mathematical Sciences

Annemieke Mulders

Dr Annemieke Mulders

Senior Lecturer - Physics
PhD Delft Uni, Netherlands

 

Telephone:  +61 2 6268 8884
Fax: +61 2 6268 8786
Email:   a.mulders@adfa.edu.au
Location:  PEMS Sth, Room G24

My UNSW Research Gateway Profile

Research Interests: condensed matter physics

 

Biography

Annemieke Mulders joined UNSW@ADFA in April 2010 as Senior Lecturer.

She completed her PhD in 1998 at the former Interfaculty Reactor Institute of Delft University of Technology in the Netherlands, focussing on magnetic properties of rare earth intermetallic compounds using neutron and muon techniques in addition to Mössbauer spectroscopy.

After working as an engineer at ASM Lithography she joined Monash University in Melbourne as a postdoctoral researcher studying two dimensional magnetism with neutron scattering techniques. From there she moved to Uppsala University in Sweden to pursue research with synchrotron radiation on magnetic nano-scaled systems. She continued her synchrotron experience at the Swiss Light Source exploring magnetic, orbital and charge order with resonant Bragg diffraction. She returned to Australia in 2006 as Bragg Research Fellow in a joint appointment between Curtin University and the Bragg Institute at ANSTO.

She is the author or co-author of over 50 refereed scientific papers.

Research

The main field of my research is neutron scattering and x-ray diffraction and spectroscopy on systems with strongly correlated electrons, in particular multiferroic materials. A strong coupling between ferroelectric and magnetic interactions is present in multiferroic materials, yet its origin is largely unknown. Such materials are promising candidates for novel applications that can dramatically increase data storage capacity and processing speeds. Two materials in particular, LuFe2O4 and hexaferrite, have the potential to be room temperature multiferroics. I recorded the first experimental evidence of an orbital glass state in LuFe2O4 using resonant x-ray diffraction (PRL 103, 077602 (2009)) and investigate magnetic hexaferrite with soft x-ray resonant diffraction under combined magnetic and electric field to search for signatures in the ferroelectric moment.

Summary of Research Interests:-

Condensed matter physics in the area of strongly correlated electron systems, using neutron scattering and synchrotron based techniques, focussed in the areas of

Multiferroic Materials

Materials which are either magnetic or ferroelectric are essential for modern information technologies. In multiferroic materials both properties ferroelectric polarization and ferromagnetic order exist simultaneously.

These properties make them extremely useful in devices where the coexistence of both charge and spin components can be exploited and one property can be used to drive the other. The potential technological applications are significant. Control of magnetic components in memory storage devices through electric manipulation will provide faster storage and retrieval of information.

For example, the combination of both switchable properties, the magnetic order and the electric polarization, on one data storage device would enhance the amount of stored data by 5 orders of magnitude. Thus, the area currently required for 1 megabyte of information would be capable to carry 1 terabyte. Technological applications are in the field of novel sensor applications where the interaction between magnetism and ferroelectric order can be exploited.

Furthermore, the advantages of piezoelectric properties in ceramic multilayer structures devices in combined piezoelectric and pyroelectric materials where an electric charge is generated by stress or temperature, respectively, can be utilized as well. Therefore, the search for new materials with these combined properties and the understanding of the physical effects behind these phenomena are essential for the development of an entire class of future multifunctional devices.

We use neutron and synchrotron based techniques to investigate the magnetic and ferroelectric properties at an atomic level, and aim to understand the physical effects that cause these desirable properties.

Current research projects

Selected Publications

  1. Triakontadipole and high-order dysprosium multipoles in the antiferromagnetic phase of DyB2C2, Princep, A.J., Mulders, A.M., Staub, U., Scagnoli, V., Nakamura, T., Kikkawa, A., Lovesey, S. & Balcar, E., 2011, Journal of Physics: Condensed Matter, 23(26), 266002 (7 pp.), doi:10.1088/0953-8984/23/26/266002
  2. Spatial fluctuations of loose spin coupling in CuMn/Co multilayers, Saerbeck, T., Loh, N., Lott, D., Toperverg, B.P., Mulders, A.M., Fraile Rodriguez, A., Freeland, J.W., Ali, M., Hickey, B.J., Stampfl, A.P.J., Klose, F. & Stamps, R.L., 2011, Physical Review Letters, 107(12), 127201-1 - 127201-4, http://link.aps.org/doi/10.1103/PhysRevLett.107.127201
  3. Ferroelectric charge order stabilized by antiferromagnetism in multiferroic LuFe2O4, Mulders, A.M., Bartkowiak, M., Hester, J.R., Pomjakushina, E. & Conder, K.,2011, Physical Review B, 84(14),140403-1 - 140403-5, http://link.aps.org/doi/10.1103/PhysRevB.84.140403
  4. Symmetry of ferroelectric phase of SrTi18O3 determined by ab initio calculations, M. Bartkowiak, G. Kearley, M. Yethiraj & A.M. Mulders, (2011), Physical Review B ,83(6),064102-1-064102-5, doi:10.1103/PhysRevB.83.064102
  5. Doping and temperature dependence of Mn 3d states in A-site ordered manganites, M. Garcia-Fernandez, , U. Staub, Y. Bodenthin, V. Pomjakushin, A. Mirone, J. Fern?ndez-Rodr?guez , V. Scagnoli, A. M. Mulders, S. M. Lawrenceand E. Pomjakushina, (2010), Physical Review B , 82(23), 235108-1-235108-8, doi:10.1103/PhysRevB.82.235108.
  6. Circularly polarized resonant soft x-ray diffraction study of helical magnetism in hexaferrite, A.M. Mulders, S.M. Lawrence, A.J. Princep, U Staub, Y Bodenthin, M Garcia-Fernandez, M Garganourakis, R Macquart and C.D. Ling, (2010) Phys. Rev. B, 81(9) 092405
  7. Direct observation of charge order and orbital glass state in multiferroic LuFe2O4, A.M. Mulders, S.M. Lawrence, U. Staub, M. Garcia-Fernandez, V. Scagnoli, C. Mazzoli, E. Pomjakushina, K. Conder, Y. Wang (2009), Phys. Rev. Lett. 103(7) 077602.
  8. Manipulating 4f quadrupolar pair-interactions in TbB2C2 using a magnetic field, A. M. Mulders, U. Staub, V. Scagnoli, Y. Tanaka, A. Kikkawa, K. Katsumata, and J. M. Tonnerre (2007), Phys. Rev. B 75(18) 184438.
  9. Charge/orbital ordering vs. Jahn-Teller distortion in La0.5Sr1.5MnO4, U. Staub, V. Scagnoli, A.M. Mulders, M. Janousch, Z. Honda and J.M. Tonnerre (2006), Europhysics Letters 76(5) pp926-932.
  10. High-order Dy multipole motifs observed in DyB2C2 with resonant soft x-ray Bragg diffraction, A.M. Mulders, U. Staub, V. Scagnoli, S.W. Lovesey, E Balcar, T. Nakamura, A. Kikkawa, G van der Laan and J.M. Tonnerre (2006), J. Phys.: Condens. Matter. 18(49) 11195.
  11. Imaging of magnetic nano dots on self-organized semiconductor substrates, A. M. Mulders, A. Fraile Rodríguez, D. Arvanitis, S. Abermann, C. Hofer, S. Kremmer, C. Teichert, M.Á Niño, J. Camarero, J.J. de Miguel, R. Miranda, S. Heun and A. Locatelli (2005), Phys. Rev. B 71(21) 214422.
  12. Orbital dynamics of the 4f shell in DyB2C2, U. Staub, A.M. Mulders, O. Zaharko, S. Janssen, T. Nakamura and S.W. Lovesey (2005), Phys. Rev. Lett. 94(3) 036408.
  13. Muon location and muon dynamics in DyNi5, A.M. Mulders, C.T. Kaiser, S.J. Harker, P.C.M. Gubbens, A. Amato, F.N. Gygax, A. Schenck, P. Dalmas de Réotier, A. Yaouanc, K.H.J. Buschow and A.A. Menovsky(2003), Phys. Rev. B. 67(1) 014303.