Dr Aidan Hindmarch
MPhys, PhD., FHEA
|Member of the Centre for Materials Physics||144E||+44 (0) 191 33 43750|
In the 2019/20 academic year I am the Level 2 Laboratory Skills & Electronics module leader. I lecture the Broken Symmetry component of Level 3 Condensed Matter Physics, and the Level 2 Electronics course. I am level 2 Electronics labs course leader, and I supervise Level 2 laboratory skills classes. I supervise two Level 4 research project students working on experimental nanoscale magnetism.
I currently supervise five PhD students: Ariam Mora-Hernandez, Ben Nicholson and Charles Swindells (all fourth year); Luke Turnbull (second year); and Kalel Alsaeed (first year) all of whom work on spintronics and nanoscale magnetism.
I teach a postgraduate course on 'Data Acquisition' as part of the MSc in Scientific Computing and Data Analysis (MISCADA).
I chair the departmental Teaching Laboratories committee, where I also represent level 2 laboratories as module leader. As part of the Teaching Laboratories committee chair's role I also sit on the departmental Education committee, Undergraduate Student-Staff Consultative committee, Health & Safety committee, and Facilities committee. I sit on the Facilities committee also as academic-staff 'Champion' for the department's Mechanical Engineering Services facility, and on the Postgraduate Course Directors committee representing Condensed Matter Physics.
Conventional electronics utilises only the charge of the electron: Spintronics additionally uses the intrinsic 'spin' of the electron as a further state variable to process, convey, and store information. Novel spintronic device architectures promise both enhanced capabilities and reduced power consumption: one outcome of this so-far is the massive increase in magnetic data-storage capacity in recent years, which has enabled high data-capacity consumer technologies such as personal media players, internet email and data storage, and high-definition television-on-demand services. My research centres around the fundamental physical mechanisms underpinning spin-polarized electrical conduction and magnetism in nanostructured spintronic devices. This is achieved using a combination of magnetic and electrical measurements, in conjunction with synchrotron x-ray and neutron scattering techniques.
Spin-polarised currents naturally arise in ferromagnetic metals. However, the effects which are useful in harnessing such currents for spintronics - spin-coherence, electrostatic screening, and evanescent decay lengths; electron mean-free-paths; magnetic domain-wall widths etc. - typically involve lengthscales on the nanometer scale. The passage of spin-polarised currents through a device is intrinsically linked to the detailed electronic structure of materials, making it possible to probe fundamental quantum-mechanical effects in magnetic nanostructures from something as simple as electrical resistance measurements. In order to study and exploit spin-polarised currents it is often necessary to fabricate thin-film or multilayered magnetic devices: magnetic thin-films and nanostructures present a wealth of novel and interesting physics in themselves. One aspect in which I am interested is hybrid structures combining metallic magnetic materials with semiconductors: incorporating the spin degree of freedom in inorganic semiconductor (Si, GaAs etc.) devices allows extension of traditional functionality, whilst organic semiconductors provide the scope for spintronic functionality to be added in future low-cost printable and flexible electronics.
Thin-film and Interface magnetism
Nanomaterials bridge the gap between individual atoms and bulk material: Thin-films, consisting sometimes of only a few atomic monolayers, can exhibit very different electrical and magnetic properties than their bulk counterparts due to symmetry breaking at surfaces and interfaces reducing the dimensionality of the system, whereas in nanoclusters long-range translational symmetry is entirely removed. The competition surface/interface and volume effects means that varying film thicknesses or cluster sizes over only a very small, even sub-nanometer, range can result in drastic modification to how materials behave. This provides an ideal method to engineer suitable magnetic properties for a given device application. Much of my research in this are centred on the magnetic anisotropy found in magnetic metal-inorganic semiconductor hybrid contacts: forming an atomically abrupt interface between nanoscale layers of different classes of material often produces novel, interesting, and technologically useful effects.
Deposition and fabrication of thin-film devices
Functionality of many of the layered structures relevant for present and future spintronic devices relies heavily on the exact structure of the device materials on an atomic scale: crystal structure and orientation; abrupt, smooth layer interfaces and pattern definition etc., in addition to avoiding damage to the underlying material or structure during fabrication. In addition to a degree of control required in order to fabricate modern devices, the material growth techniques employed must also be suitable for the high throughput, rapid turnaround manufacturing processes required for large-scale industrial application.
Synchrotron x-ray & neutron scattering
Large scale facilities provide the ability to investigate both structure and magnetism in nanomaterials and devices. Synchrotron techniques allow element-specific structural and magnetic characterisation, in addition to nanoscale imaging. Neutron reflectivity methods are used to determine vector magnetization depth-profiles of buried structures and interfaces. National and international facilities are used in my research, including the ISIS neutron source and Diamond Light Source (UK), and the US National Synchrotron Light Source. Using these techniques provides many opportunities to understand the underlying physics behind the many magnetic interactions which can occur at surfaces and interfaces: with this understanding we are then able to tailor the material properties to provide enhanced performance and functionality in future devices (Image courtesy of NSLS, Brookhaven National Laboratory).
- Centre for Materials Physics
- Condensed Matter Physics
- Spintronic Devices
- 2019: Invited Seminar: Landau seminar series, Loughborough University, UK
- 2019: Invited speaker: UK Neutron & Muon Science and User Meeting 2019, Warwick Univerity, UK
- 2018: Invited speaker: STFC ISIS Large Scale Structures meeting 2018
- 2018: Technical program committee: IEEE International conference on Microwave Magnetics (ICMM) 2018
- 2017: Invited lecture: OP postgraduate magnetism techniques workshop 2017, Univerity of York, UK
- 2017: Invited seminar: University of Central Lancashire, UK
- 2017: Invited speaker: Royal Society of Chemistry Faraday Joint Interest Group Conference, Warwick University, UK
- 2017: Programme committee: Magnetism 2017, IOP national magnetism meeting, and session chair for 'Thin-films and nanomagnets' session, University of York, UK
- 2016: Invited lecture: IOP postgraduate magnetism techniques workshop 2016, Univerity of York, UK
- 2016: Invited speaker: Joint European Magnetics Symposium (JEMS) 2016, Glasgow, UK
- 2016: Invited speaker: WALL Marie Curie ITN School on Domain Wall Motion and Spintronics, Spetses, Greece.
- 2016: Invited speaker: XMaS users meeting 2016, University of Warwick, UK
- 2016: Plenary speaker: IOP Neutrons scattering group `Grand challenges' meeting 2016, London
- 2015: Editorial board member: Scientific Reports
- 2015: Invited lecture: IOP postgraduate magnetism techniques workshop 2015, Univerity of York, UK
- 2015: Invited Seminar: University of Cardiff
- 2015: Invited speaker: University of Newcastle Physics seminar series - first external invited speaker for new seminar series.
- 2015: Invited speaker: IOP Ireland and Seagate Technology Conference: Thin Film Fabrication and Characterisation Techniques, and Their Application in Recording Head Wafer Manufacturing
- 2015: ISIS Facilities Access Panel : Member of FAP3 - Large-scale structures at STFC ISIS neutron facility
- 2015: ISIS user committee: User representative for Large Scale Structures at STFC ISIS neutron facility
- 2015: Organiser: Durham UK-India workshop on magnetisation processes 2015
- 2015: Programme committee: Magnetism 2015, IOP national magnetism meeting, and session chair for Session 8: Skyrmions and topological effects.
- 2014: Invited lecture: IOP postgraduate magnetism techniques workshop 2014, Univerity of York, UK
- 2014: Invited speaker: Science faculty workshop on 'Technology Enhanced Learning'
- 2014: Programme committee: Magnetism 2014, inaugural IOP national magnetism meeting.
- 2014: Session co-chair: Session CV - Nanowires and Assembled Nanoparticles I, at 59th Annual Conference on Magnetism and Magnetic Materials, Honolulu, Hawaii, USA
- 2013: Invited lecture: IOP postgraduate magnetism techniques workshop 2013, Univerity of York, UK
- 2013: Invited seminar: S.N. Bose National Centre for Basic Sciences, Kolkata, India
- 2013: Invited speaker: Joint Korea-UK spintronics workshop, Rutherford Appleton Laboratory, UK.
- 2012: EPSRC Manufacturing the Future theme: Selected as one of the first members of the new Early Career Forum for Manufacturing Research, 2012-2014.
- 2012: Institute of Physics: Honorary Treasurer of IOP Magnetism group
- 2012: Invited seminar: Department of Physics, University of Leeds
- 2012: Invited speaker: Joint Korea-UK spintronics workshop, Seoul, South Korea.
- 2012: University research infrastructure funding: funding awarded by the university to begin setting up a laboratory for thin-film deposition.
- 2011: Institute of Physics: Elected member of Magnetism subject group committee.
- 2011: Invited review article: Topical review on 'Interface magnetism in ferromagnet-compound semiconductor hybrid structures' for the inaugural issue of the spintronics and nanomagnetism journal 'Spin'.
- Burn, D. M., Fan, R., Inyang, O., Tokaç, M., Bouchenoire, L., Hindmarch, A. T. & Steadman, P. (2022). Spin orbit torque driven magnetization reversal in CoFeTaB/Pt probed by resonant x-ray reflectivity. Physical Review B 106(9): 094429.
- Seemann, K.M., Gomonay, O., Mokrousov, Y., Hörner, A., Valencia, S., Klamser, P., Kronast, F., Arb, A., Hindmarch, A.T., Wixforth, A., Marrows, C.H. & Fischer, P. (2022). Magnetoelastic resonance as a probe for exchange springs at antiferromagnet-ferromagnet interfaces. Physical Review B 105(14): 144432.
- Swindells, C., Hindmarch, A. T., Gallant, A. J. & Atkinson, D. (2020). Spin current propagation through ultra-thin insulating layers in multilayered ferromagnetic systems. Applied Physics Letters 116(4): 042403.
- Inyang, O., Bouchenoire, L., Nicholson, B., Tokaç, M., Rowan-Robinson, R. M., Kinane, C. J. & Hindmarch, A. T. (2019). Threshold interface magnetization required to induce magnetic proximity effect. Physical Review B 100(17): 174418.
- Swindells, C, Hindmarch, A. T. Gallant, A. J. & Atkinson, D. (2019). Spin transport across the interface in ferromagnetic/nonmagnetic systems. Physical Review B 99(6): 064406.
- Rowan-Robinson, R. M., Hindmarch, A. T. & Atkinson, D. (2018). Efficient current-induced magnetization reversal by spin-orbit torque in Pt/Co/Pt. Journal of Applied Physics 124(18): 183901.
- Belmeguenai, M., Roussigné, Y., Bouloussa, H., Chérif, S. M., Stashkevich, A., Nasui, M., Gabor, M. S., Mora-Hernández, A., Nicholson, B., Inyang, O.-O., Hindmarch, A. T. & Bouchenoire, L. (2018). Thickness Dependence of the Dzyaloshinskii-Moriya Interaction in Co2FeAl Ultrathin Films: Effects of Annealing Temperature and Heavy-Metal Material. Physical Review Applied 9(4): 044044.
- Rowan-Robinson, R.M., Stashkevich, A.A., Roussigne, Y., Belmeguenai, M., Cherif, S-M., Thiaville, A., Hase, T.P.A., Hindmarch, A.T. & Atkinson, D. (2017). The interfacial nature of proximity-induced magnetism and the Dzyaloshinskii-Moriya interaction at the Pt/Co interface. Scientific Reports 7(1): 16835.
- Tokac, M., Kinane, C.J., Atkinson, D. & Hindmarch, A.T. (2017). Temperature Dependence of Magnetically Dead Layers in Ferromagnetic Thin-Films. AIP Advances 7(11): 115022.
- Azzawi, S., Hindmarch, A. T. & Atkinson, D. (2017). Magnetic damping phenomena in ferromagnetic thin-films and multilayers. Journal of Physics D: Applied Physics 50(47): 473001.
- Brandão, J., Azzawi, S., Hindmarch, A.T. & Atkinson, D. (2017). Understanding the role of damping and Dzyaloshinskii-Moriya interaction on dynamic domain wall behaviour in platinum-ferromagnet nanowires. Scientific Reports 7(1): 4569.
- Azzawi, S., Ganguly, A., Tokaç, M., Rowan-Robinson, R.M., Sinha, J., Hindmarch, A.T., Barman, A. & Atkinson, D. (2016). Evolution of damping in ferromagnetic/nonmagnetic thin film bilayers as a function of nonmagnetic layer thickness. Physical Review B 93(5): 054402.
- Tokaç, M., Wang, M., Jaiswal, S., Rushforth, A.W., Gallagher, B.L., Atkinson, D. & Hindmarch, A.T. (2015). Interfacial Contribution to Thickness Dependent in-plane Anisotropic Magnetoresistance. AIP Advances 5(12): 127108.
- Ganguly, Arnab, Azzawi, Sinan, Saha, Susmita, King, J. A., Rowan-Robinson, R. M., Hindmarch, A. T., Sinha, Jaivardhan, Atkinson, Del & Barman, Anjan (2015). Tunable Magnetization Dynamics in Interfacially Modified Ni81Fe19/Pt Bilayer Thin Film Microstructures. Scientific Reports 5: 17596.
- Tokaç, M., Bunyaev, S.A., Kakazei, G.N., Schmool, D.S., Atkinson, D. & Hindmarch, A.T. (2015). Interfacial Structure Dependent Spin Mixing Conductance in Cobalt Thin Films. Physical Review Letters 115(5): 056601.
- Ganguly, A., Rowan-Robinson, R.M., Haldar, A., Jaiswal, S., Sinha, J., Hindmarch, A.T., Atkinson, D. & Barman, A. (2014). Time-domain detection of current controlled magnetization damping in Pt/Ni81Fe19 bilayer and determination of Pt spin Hall angle. Applied Physics Letters 105(11): 112409.
- Rowan-Robinson, R.M., Hindmarch, A.T. & Atkinson, D. (2014). Enhanced electron-magnon scattering in ferromagnetic thin films and the breakdown of the Mott two-current model. Physical Review B 90(10): 104401.
- King, J.A., Ganguly, A., Burn, D.M., Pal, S., Sallabank, E.A., Hase, T.P.A., Hindmarch, A.T., Barman, A. & Atkinson, D. (2014). Local control of magnetic damping in ferromagnetic/non-magnetic bilayers by interfacial intermixing induced by focused ion-beam irradiation. Applied Physics Letters 104(24): 242410.
- Skinner, T.D. Wang, M., Hindmarch, A.T., Rushforth, A.W., Irvine, A.C., Heiss, D., Kurebayashi, H. & Ferguson, A.J. (2014). Spin-orbit torque opposing the Oersted torque in ultrathin Co/Pt bilayers. Applied Physics Letters 104(6): 062401.
- Wang, M., Rushforth, A.W., Hindmarch, A.T., Campion, R.P., Edmonds, K.W., Staddon, C.R., Foxon, C.T. & Gallagher, B.L. (2013). Magnetic and structural properties of (Ga,Mn)As/(Al,Ga,Mn)As bilayer films. Applied Physics Letters 102(11): 112404.
- Harnchana, V., Hindmarch, A.T., Sarahan, M.C., Marrows, C.H., Brown. A.P. & Brydson, R.M.D. (2013). Evidence for boron diffusion into sub-stoichiometric MgO (001) barriers in CoFeB/MgO-based magnetic tunnel junctions. Journal of Applied Physics 113(16): 163502.
- T. D. Skinner, H. Kurebayashi, D. Fang, D. Heiss, A. C. Irvine, A. T. Hindmarch, M. Wang, A. W. Rushforth & A. J. Ferguson (2013). Enhanced inverse spin-Hall effect in ultrathin ferromagnetic/normal metal bilayers. Applied Physics Letters 102(7): 072401.
- Parkes, D. E., Shelford, L. R., Wadley, P., Holý, V., Wang, M., Hindmarch, A. T., van der Laan, G., Campion, R. P., Edmonds, K. W., Cavill, S. A. & Rushforth, A. W. (2013). Magnetostrictive thin films for microwave spintronics. Scientific Reports 3: 2220.
- Hindmarch, A.T., Parkes, D.E. & Rushforth, A.W. (2012). Fabrication of metallic magnetic nanostructures by argon ion milling using a reversed polarity planar magnetron ion source. Vacuum 86(10): 1600-1604.
- Ciudad, D., Wen, Z.-C., Hindmarch, A.T., Negusse, E., Arena, D.A., Han, X.-F. & Marrows, C.H. (2012). Competition between cotunneling, Kondo effect, and direct tunneling in discontinuous high-anisotropy magnetic tunnel junctions. Phys. Rev. B 85: 214408.
- D. E. Parkes, S. A. Cavill, A. T. Hindmarch, P. Wadley, F. McGee, C. R. Staddon, K. W. Edmonds, R. P. Campion, B. L. Gallagher & A. W. Rushforth (2012). Non-volatile voltage control of magnetization and magnetic domain walls in magnetostrictive epitaxial thin films. Applied Physics Letters 101(7): 072402.
- Hindmarch, AT (2011). Interface magnetism in ferromagnetic metal-compound semiconductor hybrid structures. Spin 1(1): 45-69.
- Hindmarch, AT, Rushforth, AW, Campion, RP, Marrows, CH & Gallagher, BL (2011). Origin of in-plane uniaxial magnetic anisotropy in CoFeB amorphous ferromagnetic thin -films. Physical Review B (Brief Report) 83(21): 212404.
- Hindmarch, AT, Harnchana, V, Walton, AS, Brown, AP, Brydson, RMD & Marrows, CH (2011). Zirconium as a boron sink in crystalline CoFeB:MgO:CoFeB magnetic tunnel junctions. Applied Physics Express 4(1): 013002.
- Hindmarch AT, Harnchana V, Ciudad D, Negusse E, Arena DA, Brown AP, Brydson RMD & Marrows CH (2010). Magnetostructural influences of thin Mg insert layers in crystalline CoFe(B):MgO:CoFe(B) magnetic tunnel junctions. Applied Physics Letters 97(25): 252502.
- Sidorenko, AA, Pernechele, C, Lupo, P, Ghidini, M, Solzi, M, De Renzi, R, Bergenti, I, Graziosi, P, Dediu, V, Hueso, L & Hindmarch, AT (2010). Interface effects on an ultrathin Co film in multilayers based on the organic semiconductor Alq3. Applied Physics Letters 97(17): 162509.
- Hindmarch, AT, Dempsey, KJ, Ciudad, D, Negusse, E, Arena, DA & Marrows, CH (2010). Fe diffusion, oxidation, and reduction at the CoFeB:MgO interface studied by soft x-ray absorption spectroscopy and magnetic circular dichroism. Applied Physics Letters 96(9): 092501.
- Dempsey, KJ, Hindmarch AT, Wei, HX, Qin, QH, Wen, ZC, Wang, WX, Vallejo-Fernandez, G, Arena, DA, Han, XF & Marrows, CH (2010). Cotunneling enhancement of magnetoresistance in double magnetic tunnel junctions with embedded superparamagnetic NiFe nanoparticles. Physical Review B 82(21): 214415.
- Dempsey, K.J., Hindmarch, A.T., Arena, D.A. & Marrows, C.H. (2010). Tuning the coercive field of Ni and CuNi thin films with the embedding of Co nanoparticles: An element-specific study. Journal of Magnetism and Magnetic Materials 322(23): 3817–3821.
- Hindmarch AT, Arena DA, Dempsey, KJ, Henini,M & Marrows, CH (2010). Influence of deposition field on the magnetic anisotropy in epitaxial Co70Fe30 films on GaAs(001). Physical Review B 81(10): 100407.
- Seemann, KM, Makrousov, Y, Aziz, A, Miguel, J, Kronast, F, Kuch, W, Blamire, MG, Hindmarch AT, Hickey, BJ, Souza, I & Marrows, CH (2010). Spin-Orbit Strength Driven Crossover between Intrinsic and Extrinsic Mechanisms of the Anomalous Hall Effect in the Epitaxial L10-Ordered Ferromagnets FePd and FePt. Physical Review Letters 104(7): 076402
- Dempsey, K.J., Hindmarch, A.T., Marrows, C.H., Wei, H.X., Qin, Q.H., Wen, Z.C. & Han, X.F. (2009). Spin-dependent tunneling through NiFe nanoparticles. Journal of Applied Physics 105(7): 07C923.
- Hindmarch, A.T., Suszka, A.K., MacKenzie, M., Chapman, J.N., Henini, M., Taylor, D., Hickey, B.J. & Marrows, C.H. (2009). Structural and magnetic properties of magnetron sputtered Co70Fe30 films on GaAs(110). Journal of Applied Physics 105(7): 073907.
- Hindmarch, AT, Kinane, CJ, MacKenzie,M, Chapman, JN, Henini, M, Taylor, D, Arena, DA, Dvorak, J, Hickey, BJ & Marrows, CH (2008). Interface induced uniaxial magnetic anisotropy in amorphous CoFeB films on AlGaAs(001). Physical Review Letters 100(11): 117201.
- Hindmarch, A.T., Dempsey, K.J., Morgan, J.P., Hickey, B.J., Arena, D.A. & Marrows, C.H. (2008). Room temperature magnetic stabilization of buried cobalt nanoclusters within a ferromagnetic matrix studied by soft x-ray magnetic circular dichroism. Applied Physics Letters 93(17): 172511.
- Harnchana, V., Brown, A.P., Brydson, R.M., Harrington, J.P., Hindmarch, A.T., Marrows, C.H. & Hickey, B.J. (2008). TEM Characterization of a Magnetic Tunnel Junction - art. no. 012058. Emag: Electron Microscopy and Analysis Group Conference 2007 126: 12058-12058.
- Hindmarch, A.T., Kinane, C.J., Marrows, C.H., Hickey, B.J., Henini, M., Taylor, D., Arena, D.A. & Dvorak, J. (2007). In-plane magnetic anisotropies of sputtered Co0.7Fe0.3 films on AlGaAs(001) spin light emitting diode heterostructures. Journal of Applied Physics 101(9): 09D106.
- Hindmarch, A.T., Marrows, C.H. & Hickey, B.J. (2007). Additional sub-gap conductance enhancement in nanoscale Andreev point contact junctions. Journal of Physics: Condensed Matter 19(13): 136211.
- Hindmarch, A.T., Anderson, G.I.R., Marrows, C.H. & Hickey, B.J. (2006). In situ transport in alumina-based magnetic tunnel junctions during high-vacuum annealing. Journal of Applied Physics 99(8): 08K701.
- Anderson, G.I.R., Hindmarch, A.T., Marrows, C.H. & Hickey, B.J. (2006). In situ transport measurements of plasma-oxidized MgO magnetic tunnel junctions during the annealing process. Journal of Applied Physics 99(8): 08T311.
- Hindmarch, A.T., Marrows, C.H. & Hickey, B.J. (2006). Temperature-driven band motion prior to the phase transition of an itinerant ferromagnet. Journal of Applied Physics 99(8): 08E501.
- Hindmarch, A.T., Marrows, C.H. & Hickey, B.J. (2005). Tunneling magnetoresistance spectroscopy: Temperature dependent spin-polarized band structure in Cu38Ni62. Physical Review B 72(6): 060406.
- Hindmarch, A.T., Marrows, C.H. & Hickey, B.J. (2005). Tunneling spin polarization in magnetic tunnel junctions near the Curie temperature. Physical Review B 72(10): 100401.
- Hindmarch, A.T. & Hickey, B.J. (2003). Direct experimental evidence for the Ruderman-Kittel-Kasuya-Yosida interaction in rare-earth metals. Physical Review Letters 91(11): 116601.
- Marrows, C.H., Langridge, S., Ali, M., Hindmarch, A.T., Dekadjevi, D.T., Foster, S. & Hickey, B.J. (2002). Mapping domain disorder in exchange-biased magnetic multilayers. Physical Review B 66(2): 024437.
- Barman, A., Kruglyak, V.V., Hicken, R.J., Marrows, C.H., Ali, M., Hindmarch, A.T. & Hickey, B.J. (2002). Characterization of spin valves fabricated on opaque substrates by optical ferromagnetic resonance. Applied Physics Letters 81(8): 1468-1470.
- Steadman, P., Ali, M., Hindmarch, A.T., Marrows, C.H., Hickey, B.J., Langridge, S., Dalgliesh, R.M. & Foster, S. (2002). Exchange bias in spin-engineered double superlattices. Physical Review Letters 89(7): 077201.