Photo of Dr Liam O'Brien

Dr Liam O'Brien

Lecturer Physics

    Publications

    Selected Publications

    1. Emergent reduced dimensionality by vertex frustration in artificial spin ice (Journal article - 2015)
    2. Kondo physics in non-local metallic spin transport devices (Journal article - 2014)
    3. Crystallites of magnetic charges in artificial spin ice (Journal article - 2013)
    4. Tunable Remote Pinning of Domain Walls in Magnetic Nanowires (Journal article - 2011)
    5. Near-Field Interaction between Domain Walls in Adjacent Permalloy Nanowires (Journal article - 2009)

    2019

    Magnetic impurities as the origin of the variability in spin relaxation rates in Cu-based spin transport devices (Journal article)

    Watts, J. D., O'Brien, L., Jeong, J. S., Mkhoyan, K. A., Crowell, P. A., & Leighton, C. (2019). Magnetic impurities as the origin of the variability in spin relaxation rates in Cu-based spin transport devices. PHYSICAL REVIEW MATERIALS, 3(12). doi:10.1103/PhysRevMaterials.3.124409

    DOI: 10.1103/PhysRevMaterials.3.124409

    Controlling All-Optical Helicity-Dependent Switching in Engineered Rare-Earth Free Synthetic Ferrimagnets (Journal article)

    Liao, J. -W., Vallobra, P., O'Brien, L., Atxitia, U., Raposo, V., Petit, D., . . . Cowburn, R. P. (2019). Controlling All-Optical Helicity-Dependent Switching in Engineered Rare-Earth Free Synthetic Ferrimagnets. ADVANCED SCIENCE, 6(24). doi:10.1002/advs.201901876

    DOI: 10.1002/advs.201901876

    When do Anisotropic Magnetic Susceptibilities Lead to Large NMR Shifts? Exploring Particle Shape Effects in the Battery Electrode Material LiFePO4. (Journal article)

    Pigliapochi, R., O'Brien, L., Pell, A. J., Gaultois, M. W., Janssen, Y., Khalifah, P., & Grey, C. P. (2019). When do Anisotropic Magnetic Susceptibilities Lead to Large NMR Shifts? Exploring Particle Shape Effects in the Battery Electrode Material LiFePO4.. Journal of the American Chemical Society, 141(33), 13089-13100. doi:10.1021/jacs.9b04674

    DOI: 10.1021/jacs.9b04674

    2017

    All-optical switching behaviours in synthetic ferrimagnetic heterostructures with different ferromagnetic-layer Curie temperatures (Conference Paper)

    Liao, J., Vallobra, P., Petit, D., Vemulkar, T., O'Brien, L., Malinowski, G., . . . Cowburn, R. (2017). All-optical switching behaviours in synthetic ferrimagnetic heterostructures with different ferromagnetic-layer Curie temperatures. In 2017 IEEE International Magnetics Conference (INTERMAG). IEEE. doi:10.1109/intmag.2017.8008016

    DOI: 10.1109/intmag.2017.8008016

    Potential resolution to the doping puzzle in iron pyrite: Carrier type determination by Hall effect and thermopower (Journal article)

    Zhang, X., Li, M., Walter, J., O'Brien, L., Manno, M. A., Voigt, B., . . . Leighton, C. (2017). Potential resolution to the doping puzzle in iron pyrite: Carrier type determination by Hall effect and thermopower. PHYSICAL REVIEW MATERIALS, 1(1). doi:10.1103/PhysRevMaterials.1.015402

    DOI: 10.1103/PhysRevMaterials.1.015402

    Room temperature spin Kondo effect and intermixing in Co/Cu non-local spin valves (Journal article)

    Watts, J. D., Jeong, J. S., O'Brien, L., Mkhoyan, K. A., Crowell, P. A., & Leighton, C. (2017). Room temperature spin Kondo effect and intermixing in Co/Cu non-local spin valves. APPLIED PHYSICS LETTERS, 110(22). doi:10.1063/1.4984896

    DOI: 10.1063/1.4984896

    Theory of Kondo suppression of spin polarization in nonlocal spin valves (Journal article)

    Kim, K. -W., O'Brien, L., Crowell, P. A., Leighton, C., & Stiles, M. D. (2017). Theory of Kondo suppression of spin polarization in nonlocal spin valves. PHYSICAL REVIEW B, 95(10). doi:10.1103/PhysRevB.95.104404

    DOI: 10.1103/PhysRevB.95.104404

    2016

    Observation and modelling of ferromagnetic contact-induced spin relaxation in Hanle spin precession measurements (Journal article)

    O'Brien, L., Spivak, D., Krueger, N., Peterson, T. A., Erickson, M. J., Bolon, B., . . . Crowell, P. A. (2016). Observation and modelling of ferromagnetic contact-induced spin relaxation in Hanle spin precession measurements. PHYSICAL REVIEW B, 94(9). doi:10.1103/PhysRevB.94.094431

    DOI: 10.1103/PhysRevB.94.094431

    Efficient spin transport through native oxides of nickel and permalloy with platinum and gold overlayers (Journal article)

    Zink, B. L., Manno, M., O'Brien, L., Lotze, J., Weiler, M., Bassett, D., . . . Leighton, C. (2016). Efficient spin transport through native oxides of nickel and permalloy with platinum and gold overlayers. PHYSICAL REVIEW B, 93(18). doi:10.1103/PhysRevB.93.184401

    DOI: 10.1103/PhysRevB.93.184401

    Interdiffusion-controlled Kondo suppression of injection efficiency in metallic nonlocal spin valves (Journal article)

    O'Brien, L. D. A., Spivak, D., Jeong, J. S., Mkhoyan, K. A., Crowell, P. A., & Leighton, C. (2016). Interdiffusion-controlled Kondo suppression of injection efficiency in metallic nonlocal spin valves. PHYSICAL REVIEW B, 93(1). doi:10.1103/PhysRevB.93.014413

    DOI: 10.1103/PhysRevB.93.014413

    2015

    Emergent reduced dimensionality by vertex frustration in artificial spin ice (Journal article)

    Gilbert, I., Lao, Y., Carrasquillo, I., O'Brien, L., Watts, J. D., Manno, M., . . . Schiffer, P. (2016). Emergent reduced dimensionality by vertex frustration in artificial spin ice. NATURE PHYSICS, 12(2), 162-+. doi:10.1038/NPHYS3520

    DOI: 10.1038/NPHYS3520

    Zinc oxide nanocrucible arrays for magnetic nanodot synthesis via ALD-assisted block polymer lithography (Conference Paper)

    Gladfelter, W., Lin, C. -H., Polisetty, S., O'Brien, L., Baruth, A., Hillmyer, M., & Leighton, C. (2015). Zinc oxide nanocrucible arrays for magnetic nanodot synthesis via ALD-assisted block polymer lithography. In ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY Vol. 250. Retrieved from http://gateway.webofknowledge.com/

    Size-Tuned ZnO Nanocrucible Arrays for Magnetic Nanodot Synthesis via Atomic Layer Deposition-Assisted Block Polymer Lithography (Journal article)

    Lin, C. -H., Polisetty, S., O'Brien, L., Baruth, A., Hilimyer, M. A., Leighton, C., & Gladfelter, W. L. (2015). Size-Tuned ZnO Nanocrucible Arrays for Magnetic Nanodot Synthesis via Atomic Layer Deposition-Assisted Block Polymer Lithography. ACS Nano, 9(2), 1379-1387. doi:10.1021/nn505731n

    DOI: 10.1021/nn505731n

    Effects of exchange bias on magnetotransport in permalloy kagome artificial spin ice (Journal article)

    Le, B. L., Rench, D. W., Misra, R., O'Brien, L., Leighton, C., Samarth, N., & Schiffer, P. (2015). Effects of exchange bias on magnetotransport in permalloy kagome artificial spin ice. NEW JOURNAL OF PHYSICS, 17. doi:10.1088/1367-2630/17/2/023047

    DOI: 10.1088/1367-2630/17/2/023047

    2014

    Emergent ice rule and magnetic charge screening from vertex frustration in artificial spin ice (Journal article)

    Gilbert, I., Chern, G. -W., Zhang, S., O'Brien, L., Fore, B., Nisoli, C., & Schiffer, P. (2014). Emergent ice rule and magnetic charge screening from vertex frustration in artificial spin ice. Nature Physics, 10(9), 670-675. doi:10.1038/NPHYS3037

    DOI: 10.1038/NPHYS3037

    Resonance in magnetostatically coupled transverse domain walls (Journal article)

    Galkiewicz, A. T., O'Brien, L., Keatley, P. S., Cowburn, R. P., & Crowell, P. A. (2014). Resonance in magnetostatically coupled transverse domain walls. PHYSICAL REVIEW B, 90(2). doi:10.1103/PhysRevB.90.024420

    DOI: 10.1103/PhysRevB.90.024420

    Kondo physics in non-local metallic spin transport devices (Journal article)

    O'Brien, L., Erickson, M. J., Spivak, D., Ambaye, H., Goyette, R. J., Lauter, V., . . . Leighton, C. (2014). Kondo physics in non-local metallic spin transport devices. NATURE COMMUNICATIONS, 5. doi:10.1038/ncomms4927

    DOI: 10.1038/ncomms4927

    Time-resolved Kerr microscopy of coupled transverse domain walls in a pair of curved nanowires (Journal article)

    Keatley, P. S., Yu, W., O'Brien, L., Read, D. E., Cowburn, R. P., & Hicken, R. J. (2014). Time-resolved Kerr microscopy of coupled transverse domain walls in a pair of curved nanowires. JOURNAL OF APPLIED PHYSICS, 115(17). doi:10.1063/1.4865211

    DOI: 10.1063/1.4865211

    2013

    Crystallites of magnetic charges in artificial spin ice (Journal article)

    Zhang, S., Gilbert, I., Nisoli, C., Chern, G. -W., Erickson, M. J., O'Brien, L., . . . Schiffer, P. (2013). Crystallites of magnetic charges in artificial spin ice. NATURE, 500(7464), 553-557. doi:10.1038/nature12399

    DOI: 10.1038/nature12399

    Coupling and induced depinning of magnetic domain walls in adjacent spin valve nanotracks (Journal article)

    Sampaio, J., O'Brien, L., Petit, D., Read, D. E., Lewis, E. R., Zeng, H. T., . . . Cowburn, R. P. (2013). Coupling and induced depinning of magnetic domain walls in adjacent spin valve nanotracks. JOURNAL OF APPLIED PHYSICS, 113(13). doi:10.1063/1.4798943

    DOI: 10.1063/1.4798943

    Three dimensional magnetic nanowires grown by focused electron-beam induced deposition (Journal article)

    Fernandez-Pacheco, A., Serrano-Ramon, L., Michalik, J. M., Ricardo Ibarra, M., De Teresa, J. M., O'Brien, L., . . . Cowburn, R. P. (2013). Three dimensional magnetic nanowires grown by focused electron-beam induced deposition. SCIENTIFIC REPORTS, 3. doi:10.1038/srep01492

    DOI: 10.1038/srep01492

    2012

    Domain wall interactions at a cross-shaped vertex (Journal article)

    O'Brien, L., Beguivin, A., Petit, D., Fernandez-Pacheco, A., Read, D., & Cowburn, R. P. (2012). Domain wall interactions at a cross-shaped vertex. PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES, 370(1981), 5794-5805. doi:10.1098/rsta.2012.0089

    DOI: 10.1098/rsta.2012.0089

    Magnetic domain wall induced, localized nanowire reversal (Journal article)

    O'Brien, L., Beguivin, A., Fernandez-Pacheco, A., Petit, D., Read, D. E., & Cowburn, R. P. (2012). Magnetic domain wall induced, localized nanowire reversal. APPLIED PHYSICS LETTERS, 101(6). doi:10.1063/1.4742746

    DOI: 10.1063/1.4742746

    Dynamic Oscillations of Coupled Domain Walls (Journal article)

    O'Brien, L., Lewis, E. R., Fernandez-Pacheco, A., Petit, D., Cowburn, R. P., Sampaio, J., & Read, D. E. (2012). Dynamic Oscillations of Coupled Domain Walls. PHYSICAL REVIEW LETTERS, 108(18). doi:10.1103/PhysRevLett.108.187202

    DOI: 10.1103/PhysRevLett.108.187202

    Correlation between the magnetic imaging of cobalt nanoconstrictions and their magnetoresistance response (Journal article)

    Fernandez-Pacheco, A., Serrano-Ramon, L. E., Tyliszczak, T., Chou, K. W., Cordoba, R., Szkudlarek, A., . . . De Teresa, J. M. (2012). Correlation between the magnetic imaging of cobalt nanoconstrictions and their magnetoresistance response. NANOTECHNOLOGY, 23(10). doi:10.1088/0957-4484/23/10/105703

    DOI: 10.1088/0957-4484/23/10/105703

    Dynamic propagation and nucleation in domain wall nanowire devices (Journal article)

    O'Brien, L., Read, D. E., Petit, D., & Cowburn, R. P. (2012). Dynamic propagation and nucleation in domain wall nanowire devices. JOURNAL OF PHYSICS-CONDENSED MATTER, 24(2). doi:10.1088/0953-8984/24/2/024222

    DOI: 10.1088/0953-8984/24/2/024222

    2011

    Magnetisation reversal in permalloy nanowires controlled by near-field charge interactions (Journal article)

    Beguivin, A., O'Brien, L. A., Jausovec, A. V., Petit, D., & Cowburn, R. P. (2011). Magnetisation reversal in permalloy nanowires controlled by near-field charge interactions. APPLIED PHYSICS LETTERS, 99(14). doi:10.1063/1.3646548

    DOI: 10.1063/1.3646548

    Chirality dependence of nanoscale ferromagnetic NOT gates (Journal article)

    Lewis, E. R., Petit, D., O'Brien, L., Zeng, H. T., Read, D. E., & Cowburn, R. P. (2011). Chirality dependence of nanoscale ferromagnetic NOT gates. JOURNAL OF APPLIED PHYSICS, 109(5). doi:10.1063/1.3549599

    DOI: 10.1063/1.3549599

    Tunable Remote Pinning of Domain Walls in Magnetic Nanowires (Journal article)

    O'Brien, L., Petit, D., Lewis, E. R., Cowburn, R. P., Read, D. E., Sampaio, J., . . . Jausovec, A. -V. (2011). Tunable Remote Pinning of Domain Walls in Magnetic Nanowires. PHYSICAL REVIEW LETTERS, 106(8). doi:10.1103/PhysRevLett.106.087204

    DOI: 10.1103/PhysRevLett.106.087204

    Kinetic depinning of a magnetic domain wall above the Walker field (Journal article)

    Lewis, E. R., Petit, D., O'Brien, L., Jausovec, A. -V., Zeng, H. T., Read, D. E., & Cowburn, R. P. (2011). Kinetic depinning of a magnetic domain wall above the Walker field. APPLIED PHYSICS LETTERS, 98(4). doi:10.1063/1.3543844

    DOI: 10.1063/1.3543844

    2010

    Magnetic imaging of the pinning mechanism of asymmetric transverse domain walls in ferromagnetic nanowires (Journal article)

    Petit, D., Zeng, H. T., Sampaio, J., Lewis, E., O'Brien, L., Jausovec, A. -V., . . . Chapman, J. N. (2010). Magnetic imaging of the pinning mechanism of asymmetric transverse domain walls in ferromagnetic nanowires. APPLIED PHYSICS LETTERS, 97(23). doi:10.1063/1.3523351

    DOI: 10.1063/1.3523351

    Fast domain wall motion in magnetic comb structures (Journal article)

    Lewis, E. R., Petit, D., O'Brien, L., Fernandez-Pacheco, A., Sampaio, J., Jausovec, A. -V., . . . Cowburn, R. P. (2010). Fast domain wall motion in magnetic comb structures. NATURE MATERIALS, 9(12), 980-983. doi:10.1038/NMAT2857

    DOI: 10.1038/NMAT2857

    The influence of wire width on the charge distribution of transverse domain walls and their stray field interactions (Journal article)

    Zeng, H. T., Petit, D., O'Brien, L., Read, D., Lewis, E. R., & Cowburn, R. P. (2010). The influence of wire width on the charge distribution of transverse domain walls and their stray field interactions. JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 322(14), 2010-2014. doi:10.1016/j.jmmm.2010.01.024

    DOI: 10.1016/j.jmmm.2010.01.024

    Asymmetric magnetic NOT gate and shift registers for high density data storage (Journal article)

    Zeng, H. T., Read, D., O'Brien, L., Sampaio, J., Lewis, E. R., Petit, D., & Cowburn, R. P. (2010). Asymmetric magnetic NOT gate and shift registers for high density data storage. APPLIED PHYSICS LETTERS, 96(26). doi:10.1063/1.3457998

    DOI: 10.1063/1.3457998

    2009

    Bidirectional magnetic nanowire shift register (Journal article)

    O'Brien, L., Read, D. E., Zeng, H. T., Lewis, E. R., Petit, D., & Cowburn, R. P. (2009). Bidirectional magnetic nanowire shift register. APPLIED PHYSICS LETTERS, 95(23). doi:10.1063/1.3271683

    DOI: 10.1063/1.3271683

    Magnetization reversal in individual cobalt micro- and nanowires grown by focused-electron-beam-induced-deposition (Journal article)

    Fernandez-Pacheco, A., De Teresa, J. M., Szkudlarek, A., Cordoba, R., Ibarra, M. R., Petit, D., . . . Cowburn, R. P. (2009). Magnetization reversal in individual cobalt micro- and nanowires grown by focused-electron-beam-induced-deposition. NANOTECHNOLOGY, 20(47). doi:10.1088/0957-4484/20/47/475704

    DOI: 10.1088/0957-4484/20/47/475704

    Magnetic domain wall pinning by a curved conduit (Journal article)

    Lewis, E. R., Petit, D., Thevenard, L., Jausovec, A. V., O'Brien, L., Read, D. E., & Cowburn, R. P. (2009). Magnetic domain wall pinning by a curved conduit. APPLIED PHYSICS LETTERS, 95(15). doi:10.1063/1.3246154

    DOI: 10.1063/1.3246154

    Near-Field Interaction between Domain Walls in Adjacent Permalloy Nanowires (Journal article)

    O'Brien, L., Petit, D., Zeng, H. T., Lewis, E. R., Sampaio, J., Jausovec, A. V., . . . Cowburn, R. P. (2009). Near-Field Interaction between Domain Walls in Adjacent Permalloy Nanowires. PHYSICAL REVIEW LETTERS, 103(7). doi:10.1103/PhysRevLett.103.077206

    DOI: 10.1103/PhysRevLett.103.077206

    Mechanism for domain wall pinning and potential landscape modification by artificially patterned traps in ferromagnetic nanowires (Journal article)

    Petit, D., Jausovec, A. -V., Zeng, H. T., Lewis, E., O'Brien, L., Read, D., & Cowburn, R. P. (2009). Mechanism for domain wall pinning and potential landscape modification by artificially patterned traps in ferromagnetic nanowires. PHYSICAL REVIEW B, 79(21). doi:10.1103/PhysRevB.79.214405

    DOI: 10.1103/PhysRevB.79.214405

    Domain wall conduit behavior in cobalt nanowires grown by focused electron beam induced deposition (Journal article)

    Fernandez-Pacheco, A., De Teresa, J. M., Cordoba, R., Ibarra, M. R., Petit, D., Read, D. E., . . . Cowburn, R. P. (2009). Domain wall conduit behavior in cobalt nanowires grown by focused electron beam induced deposition. APPLIED PHYSICS LETTERS, 94(19). doi:10.1063/1.3139068

    DOI: 10.1063/1.3139068

    Combined electrical and magneto-optical measurements of the magnetization reversal process at a domain wall trap. (Journal article)

    Zeng, H. T., Read, D., Petit, D., Jausovec, A. V., O'Brien, L., Lewis, E. R., & Cowburn, R. P. (2009). Combined electrical and magneto-optical measurements of the magnetization reversal process at a domain wall trap.. APPLIED PHYSICS LETTERS, 94(10). doi:10.1063/1.3098359

    DOI: 10.1063/1.3098359

    Measuring Domain Wall Fidelity Lengths Using a Chirality Filter (Journal article)

    Lewis, E. R., Petit, D., Jausovec, A. -V., O'Brien, L., Read, D. E., Zeng, H. T., & Cowburn, R. P. (2009). Measuring Domain Wall Fidelity Lengths Using a Chirality Filter. PHYSICAL REVIEW LETTERS, 102(5). doi:10.1103/PhysRevLett.102.057209

    DOI: 10.1103/PhysRevLett.102.057209

    2008

    High efficiency domain wall gate in ferromagnetic nanowires (Journal article)

    Petit, D., Jausovec, A. -V., Zeng, H. T., Lewis, E., O'Brien, L., Read, D., & Cowburn, R. P. (2008). High efficiency domain wall gate in ferromagnetic nanowires. APPLIED PHYSICS LETTERS, 93(16). doi:10.1063/1.3005586

    DOI: 10.1063/1.3005586