My field of specialisation is in materials science, particularly in the synthesis, understandings and optimisation of room temperature ferroelectric and multiferroic thin films for beyond CMOS data storage applications.
Our digital universe is doubling in size every two years. The International Data Corporation predicts that by 2020 it will contain nearly as many digital bits as there are stars in the observable universe! Multiferroic materials, possessing simultaneous electric and magnetic memory states, have been road-mapped as promising multi-state architectures for memory scaling beyond current technologies. No such devices currently exist however, as multiferroic materials with room temperature properties are extremely rare.
Based on my understandings of dielectric and magnetic materials and on my expertise in the synthesis of complex and advanced materials, I designed a material system (Aurivillius phase, Bi6TixFeyMnzO18) that exhibits multiferroic (ferroelectric and ferromagnetic) properties in a single homogeneous phase at ambient temperatures. Direct evidence for magnetic-field-induced ferroelectric domain switching at the nanoscale was demonstrated by using piezoresponse microscopy (PFM) under a variable magnetic field. Given that room temperature multiferroics are extremely scarce, development of this material has made noteworthy advances to the multiferroics field, resulting in Nature group publications (M. Schmidt, et al., Sci. Rep., 4, 5712 (2014); L. Keeney, et al., Sci. Rep., 7, 1737 (2017)) and a publication (L. Keeney, et al., J. of the Am. Ceram. Soc., 96 [8], 2339-2357 (2013)) which has been cited 114 times. My latest work demonstrates that the magnetic ions tend to congregate to the centre of the Aurivillius phase structure, aligning close to each other which would permit them to interact and create pathways for long-range magnetic order. Interestingly, the presence of sub-unit cell defects (stacking faults, out-of-phase boundaries) appears to further drive magnetic ions to the central layers. I am therefore eager to exploit this material and to address the intriguing research questions that this tantalising material opens up.
Funder | Start Date | End Date | Title | Role |
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European Union | 01-NOV-11 | 31-OCT-15 | Nanoelectromechanical Motion in Functional Materials | Principal Investigator |
Science Foundation of Ireland | 01-JAN-14 | 30-SEP-18 | New Memory cell rest structure devices based on sigle phase. | Principal Investigator |
Miscellaneous Non Exchequer | 01-OCT-15 | 21-JUN-21 | UF140263 RSC University Fellowship Lynette Keeney [X] | Principal Investigator |
Intel Corporation | 01-APR-16 | 31-MAR-17 | Development of test structure to characterize properties of Multiferroic material(s) | |
Science Foundation of Ireland | 03-FEB-17 | 31-DEC-17 | SFI Maternity Allowance | Principal Investigator |
Science Foundation of Ireland | 01-JAN-18 | 21-JUN-24 | Correlation of magnetic and magnetoelectric properties with crystallite orientation and sub-unit cell characteristics in room temperature multiferroic materials | Principal Investigator |
Miscellaneous | 01-JAN-19 | 31-DEC-23 | Assessment of ultra-thin multiferroic thin films for potential use in multi-state data storage applications | Principal Investigator |
Miscellaneous | 02-SEP-19 | 01-SEP-21 | Royal Irish Academy-Royal Society Int Cost-Share Exchange Program 2019 | Principal Investigator |
Science Foundation of Ireland | 01-OCT-20 | 30-SEP-24 | Optimisation of Single Phase Room Temperature Multiferroic Materials Enabling Next Generation Data Storage | Principal Investigator |
Year | Publication |
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2016 | Novel approaches for genuine single phase room temperature magnetoelectric multiferroics Lynette Keeney, Michael Schmidt, Andreas Amann, Tuhin Maity, Nitin Deepak, Ahmad Faraz, Nikolay Petkov, Saibal Roy, Martyn E Pemble, Roger W Whatmore (2016) Novel approaches for genuine single phase room temperature magnetoelectric multiferroics. : Wiley. [Details] |
Year | Journal | Publication |
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2020 | Advanced Electronic Materials | Ferroelectric behavior in exfoliated 2D Aurivillius oxide flakes of sub-unit cell thickness Keeney, Lynette; Smith, Ronan J.; Palizdar, Meghdad; Schmidt, Michael; Bell, Andrew J.; Coleman, Jonathan N.; Whatmore, Roger W. (2020) Ferroelectric behavior in exfoliated 2D Aurivillius oxide flakes of sub-unit cell thickness. : . [Details] |
2018 | Journal of Applied Physics | Exploring ferroelectric and magnetic properties of Tb-substituted m = 5 layered Aurivillius phase thin films Faraz, Ahmad; Ricote, Jesus; Jimenez, Ricardo; Maity, Tuhin; Schmidt, Michael; Deepak, Nitin; Roy, Saibal; Pemble, Martyn E.; Keeney, Lynette (2018) Exploring ferroelectric and magnetic properties of Tb-substituted m = 5 layered Aurivillius phase thin films. : . [Details] |
2017 | Journal of The American Ceramic Society | Direct visualization of magnetic-field-induced magnetoelectric switching in multiferroic Aurivillius phase thin films Faraz, Ahmad; Maity, Tuhin; Schmidt, Michael; Deepak, Nitin; Roy, Saibal; Pemble, Martyn E.; Whatmore, Roger W.; Keeney, Lynette (2017) Direct visualization of magnetic-field-induced magnetoelectric switching in multiferroic Aurivillius phase thin films. : . [Details] |
2017 | Scientific Reports | Direct atomic scale determination of magnetic ion partition in a room temperature multiferroic material Keeney, L;Downing, C;Schmidt, M;Pemble, ME;Nicolosi, V;Whatmore, RW (2017) Direct atomic scale determination of magnetic ion partition in a room temperature multiferroic material. : NATURE PUBLISHING GROUP. [Details] |
2015 | Journal of Materials Chemistry C | Tunable nanoscale structural disorder in Aurivillius phase, n= 3 Bi 4 Ti 3 O 12 thin films and their role in the transformation to n= 4, Bi 5 Ti 3 FeO 15 phase Nitin Deepak, Patrick Carolan, Lynette Keeney, Martyn E Pemble, Roger W Whatmore (2015) Tunable nanoscale structural disorder in Aurivillius phase, n= 3 Bi 4 Ti 3 O 12 thin films and their role in the transformation to n= 4, Bi 5 Ti 3 FeO 15 phase. : . |
2015 | Dalton Transactions | Quantum chemical and solution phase evaluation of metallocenes as reducing agents for the prospective atomic layer deposition of copper Gangotri Dey, Jacqueline S Wrench, Dirk J Hagen, Lynette Keeney, Simon D Elliott (2015) Quantum chemical and solution phase evaluation of metallocenes as reducing agents for the prospective atomic layer deposition of copper. : . |
2015 | Journal of Applied Physics | A study of the temperature dependence of the local ferroelectric properties of c-axis oriented Bi6Ti3Fe2O18 Aurivillius phase thin films: Illustrating the potential of a novel lead-free perovskite material for high density memory applications, AIP Advances 5, 087123 (2015) Ahmad Faraz, Nitin Deepak, Michael Schmidt, Martyn E. Pemble, Lynette Keeney (2015) A study of the temperature dependence of the local ferroelectric properties of c-axis oriented Bi6Ti3Fe2O18 Aurivillius phase thin films: Illustrating the potential of a novel lead-free perovskite material for high density memory applications, AIP Advances 5, 087123 (2015). : . [Details] |
2015 | Chemistry Materials | Bismuth Self-Limiting Growth of Ultrathin BiFeO3 Films Deepak, N;Carolan, P;Keeney, L;Zhang, PFF;Pemble, ME;Whatmore, RW (2015) Bismuth Self-Limiting Growth of Ultrathin BiFeO3 Films. : AMER CHEMICAL SOC. [Details] |
2014 | Physical Review B | Large magnetoelectric coupling in nanoscale BiFeO3 from direct electrical measurements Goswami, Sudipta; Bhattacharya, Dipten; Keeney, Lynette; Maity, Tuhin; Kaushik, S. D.; Siruguri, V.; Das, Gopes C; Yang, Haifang; Li, Wuxia; Gu, Chang-zhi; Pemble, Martyn E.; Roy, Saibal (2014) Large magnetoelectric coupling in nanoscale BiFeO3 from direct electrical measurements. : . [Details] |
2014 | Journal of Materials Chemistry C | Atomic layer deposition of Cu with a carbene-stabilized Cu (i) silylamide Hagen, Dirk J and Povey, Ian M and Rushworth, Simon and Wrench, Jacqueline S and Keeney, Lynette and Schmidt, Michael and Petkov, Nikolay and Barry, Se'an T and Coyle, Jason P and Pemble, Martyn E (2014) Atomic layer deposition of Cu with a carbene-stabilized Cu (i) silylamide. : . [Details] |
2014 | Scientific Reports | Absence of evidence ≠ evidence of absence: statistical analysis of inclusions in multiferroic thin films Schmidt, M.; Amann, A.; Keeney, L.; Pemble, M.; Holmes, J. D.; Petkov, N.; Whatmore, R. W. (2014) Absence of evidence ≠ evidence of absence: statistical analysis of inclusions in multiferroic thin films. : . [Details] |
2014 | Advanced Functional Materials | Interesting Evidence for Template-Induced Ferroelectric Behavior in Ultra-Thin Titanium Dioxide Films Grown on (110) Neodymium Gallium Oxide Substrates Deepak, Nitin and Caro, Miguel A and Keeney, Lynette and Pemble, Martyn E and Whatmore, Roger W (2014) Interesting Evidence for Template-Induced Ferroelectric Behavior in Ultra-Thin Titanium Dioxide Films Grown on (110) Neodymium Gallium Oxide Substrates. : . |
2013 | Smart Materials and Structures | Flexible-CMOS and biocompatible piezoelectric AlN material for MEMS applications Jackson, N;Keeney, L;Mathewson, A (2013) Flexible-CMOS and biocompatible piezoelectric AlN material for MEMS applications. : IOP PUBLISHING LTD. [Details] |
2013 | Journal of The American Ceramic Society | Magnetic Field-Induced Ferroelectric Switching in Multiferroic Aurivillius Phase Thin Films at Room Temperature Keeney, L,Maity, T,Schmidt, M,Amann, A,Deepak, N,Petkov, N,Roy, S,Pemble, ME,Whatmore, RW (2013) Magnetic Field-Induced Ferroelectric Switching in Multiferroic Aurivillius Phase Thin Films at Room Temperature. : . [Details] |
2013 | Journal of Applied Physics | Atomic vapor deposition of bismuth titanate thin films Deepak, N; Zhang, PF; Keeney, L; Pemble, ME; Whatmore, RW (2013) Atomic vapor deposition of bismuth titanate thin films. : . [Details] |
2012 | Journal of Applied Physics | Room temperature electromechanical and magnetic investigations of ferroelectric Aurivillius phase Bi[sub 5]Ti[sub 3](Fe[sub x]Mn[sub 1 - x])O[sub 15] (x = 1 and 0.7) chemical solution deposited thin films Lynette Keeney, Claudia Groh, Santosh Kulkarni, Saibal Roy, Martyn E. Pemble and Roger W. Whatmore (2012) Room temperature electromechanical and magnetic investigations of ferroelectric Aurivillius phase Bi[sub 5]Ti[sub 3](Fe[sub x]Mn[sub 1 - x])O[sub 15] (x = 1 and 0.7) chemical solution deposited thin films. : . [Details] |
2012 | Journal of Applied Physics | Crystallographic and magnetic identification of secondary phase in orientated Bi5Fe0.5Co0.5Ti3O15 ceramics Palizdar, M,Comyn, TP,Ward, MB,Brown, AP,Harrington, JP,Kulkarni, S,Keeney, L,Roy, S,Pemble, M,Whatmore, R,Quinn, C,Kilcoyne, SH,Bell, AJ (2012) Crystallographic and magnetic identification of secondary phase in orientated Bi5Fe0.5Co0.5Ti3O15 ceramics. : . [Details] |
2012 | Journal of Applied Physics | Room Temperature Ferroelectric and Magnetic Investigations and Detailed Phase Analysis of Aurivillius Phase Bi5Ti3Fe0.7Co0.3O15 Thin Films Lynette Keeney, Santosh Kulkarni, Nitin Deepak, Michael Schmidt, Nikolay Petkov, Panfeng F. Zhang, Stuart Cavill, Saibal Roy, Martyn E. Pemble and Roger W. Whatmore (2012) Room Temperature Ferroelectric and Magnetic Investigations and Detailed Phase Analysis of Aurivillius Phase Bi5Ti3Fe0.7Co0.3O15 Thin Films. : . [Details] |
2012 | Physical Review B | Ordered magnetic dipoles: Controlling anisotropy in nanomodulated continuous ferromagnetic films Maity, T;Li, SP;Keeney, L;Roy, S (2012) Ordered magnetic dipoles: Controlling anisotropy in nanomodulated continuous ferromagnetic films. : AMER PHYSICAL SOC. [Details] |
2012 | Nanoletters | Nanoscale Ferroelectric and Piezoelectric Properties of Sb2S3 Nanowire Arrays Varghese, J;Barth, S;Keeney, L;Whatmore, RW;Holmes, JD (2012) Nanoscale Ferroelectric and Piezoelectric Properties of Sb2S3 Nanowire Arrays. : AMER CHEMICAL SOC. [Details] |
2012 | Applied Physics Letters | The structural and piezoresponse properties of c-axis-oriented Aurivillius phase Bi5Ti3FeO15 thin films deposited by atomic vapor deposition Zhang, PF;Deepak, N;Keeney, L;Pemble, ME;Whatmore, RW (2012) The structural and piezoresponse properties of c-axis-oriented Aurivillius phase Bi5Ti3FeO15 thin films deposited by atomic vapor deposition. : AMER INST PHYSICS. [Details] |
2011 | Chemical Vapor Deposition | Nucleation and Chemical Transformation of RuO2 Films Grown on (100) Si Substrates by Atomic Layer Deposition Salaun, A,Newcomb, SB,Povey, IM,Salaun, M,Keeney, L,O'Mahony, A,Pemble, ME; (2011) Nucleation and Chemical Transformation of RuO2 Films Grown on (100) Si Substrates by Atomic Layer Deposition. : . [Details] |
2010 | Optics Communications | Moth-eye-structured light-emitting diodes Jing Rao, Lynette Keeney, Richard Winfield (2010) Moth-eye-structured light-emitting diodes. : . [Details] |
2010 | Journal of Applied Physics | Piezoresponse force microscopy investigations of Aurivillius phase thin films Keeney, Lynette; Zhang, Panfeng; Groh, Claudia; Pemble, Martyn E; Whatmore, Roger W; (2010) Piezoresponse force microscopy investigations of Aurivillius phase thin films. : . |
2009 | Dalton Transactions | Anomalously slow rates of reduction of iron(III) polypyridine complexes by triphenyl verdazyl radicals in acetonitrile Sandra Conway, Lynette Keeney and Michael J. Hynes (2009) Anomalously slow rates of reduction of iron(III) polypyridine complexes by triphenyl verdazyl radicals in acetonitrile. : . [Details] |
2005 | Dalton Transactions | Electron transfer reactions of tris(polypyridine)cobalt(III) complexes, [Co(N-N)3]3+, with verdazyl radicals in acetonitrile solution Lynette Keeney and Michael. J. Hynes (2005) Electron transfer reactions of tris(polypyridine)cobalt(III) complexes, [Co(N-N)3]3+, with verdazyl radicals in acetonitrile solution. : . [Details] |
2005 | Dalton Transactions | Kinetics and mechanisms of the electron transfer reactions of oxo-centred carboxylate bridged complexes, [Fe3([small micro]3-O)(O2CR)6L3]ClO4, with verdazyl radicals in acetonitrile solution Lynette Keeney and Michael J. Hynes (2005) Kinetics and mechanisms of the electron transfer reactions of oxo-centred carboxylate bridged complexes, [Fe3([small micro]3-O)(O2CR)6L3]ClO4, with verdazyl radicals in acetonitrile solution. : . [Details] |
Year | Publication |
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2015 | PROCEEDINGS OF THE 2015 IEEE INTERNATIONAL CONFERENCE ON MICROELECTRONIC TEST STRUCTURES (ICMTS 2015) Jackson, N;Olszewski, OZ;Keeney, L;Blake, A;Mathewson, A (2015) PROCEEDINGS OF THE 2015 IEEE INTERNATIONAL CONFERENCE ON MICROELECTRONIC TEST STRUCTURES (ICMTS 2015). : IEEE. |
2014 | ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY Gangotri Dey, Simon D Elliott, Jacqueline Wrench, Lynette Keeney, Martyn Pemble (2014) ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY. : . |
2012 | Applications of Ferroelectrics held jointly with 2012 European Conference on the Applications of Polar Dielectrics and 2012 International Symp Piezoresponse Force Microscopy and Nanoscale Phenomena in Polar Materials (ISAF/ECAPD/PFM) Deepak, N. Zhang, P., L. Keeney, Pemble, M. E. and Whatmore R. W. (2012) Applications of Ferroelectrics held jointly with 2012 European Conference on the Applications of Polar Dielectrics and 2012 International Symp Piezoresponse Force Microscopy and Nanoscale Phenomena in Polar Materials (ISAF/ECAPD/PFM). : . |
2011 | Applications of Ferroelectrics (ISAF/PFM), 2011 International Symposium on and 2011 International Symposium on Piezoresponse Force Microscopy and Nanoscale Phenomena in Polar Materials, 24-27 July 2011 , Vancouver, BC. M. Palizdar, T. P. Comyn, M. B. Ward, A. P. Brown, J. Harington, S. Kulkarni, L. Keeney, S. Roy, M. E. Pemble, R. Whatmore, C. Quinne, S. H. Kilcoyne, and A. J. Bell (2011) Applications of Ferroelectrics (ISAF/PFM), 2011 International Symposium on and 2011 International Symposium on Piezoresponse Force Microscopy and Nanoscale Phenomena in Polar Materials, 24-27 July 2011 , Vancouver, BC.. : . |
2010 | IEEE International Symposium on the Applications of Ferroelectrics (ISAF) 2010 Meghdad Palizdar; Tim Comyn; Santosh Kulkarni; Lynette Keeney; Saibal Roy; Martyn Pemble; Roger W. Whatmore (2010) IEEE International Symposium on the Applications of Ferroelectrics (ISAF) 2010. : . |
2014: Conference Chair: Symposium I (Solution processing and properties of functional oxide thin films and nanostructures), European Materials Research Symposium, Spring 2014 Meeting, Lille, France.
2014: Poster Competition Juror: Symposium I (Solution processing and properties of functional oxide thin films and nanostructures), European Materials Research Symposium, Spring 2014 Meeting, Lille, France.
2016: Conference Chair: 'Session 2a - ECAPD-ISAF Controversial Ferroelectrics and Devices' at ECAPD/ISAF/PFM, Darmstadt, 21 August 2016.
2016: Student Poster Competition Juror at ECAPD/ISAF/PFM, Darmstadt, Germany, 21 August 2016.
2013: Invited seminar ‘Room Temperature Magnetic-Field-Induced Ferroelectric Switching in Multiferroic Aurivillius Phase Thin Films’, 7th October 2013 at ETH Zürich (Prof. N. Spaldin and Prof. M. Fiebig’s groups).
2013: Industry talk ‘Room Temperature Magnetic-Field-Indu
Proposal Reviewer for The Royal Society Newton International Fellowship Panel, Panel 3: Natural Sciences (“physical” sciences)
Proposal Reviewer for The Royal Society Resilient Futures Challenge-Led Grants in the Materials Sciences discipline
Session Organiser and Chair for the Nanoelectronics: Advanced
Session chair for 'Characterization & Properties of Ferroelectrics' at ECAPD 2018
2019 to present: Local organizing committee member for the International Symposium on Integrated Functionalities, University College Dublin, August 2019.
2019: 'Best contributed talk’ judge at MSI Winter Symposium, 15-16 Jan 2019.
2019 to present: Micro-nano Systems centre academic representative of the Tyndall Graduate Studies Committee and internal examiner of Ph.D. examinations.
Lecturer and examiner of Materials Chemistry course CM1001, University College Cork.