Publications

2024

38. Harikrishnan K. P., R. Xu, K. Patel, K. J. Crust, A. Khandelwal, C. Zhang, S. Prosandeev, H. Zhou, Y. -T. Shao, L. Bellaiche, H. Y. Hwang, D. A. Muller, “Electron ptychography reveals a ferroelectricity dominated by anion displacements”, arXiv:2408.14795 [cond-mat.mtrl-sci]

37. V. Harbola, D. Pesquera, R. Xu, P. Ashby, L. W. Martin, H. Y. Hwang, “Flexoelectric enhancement of strain gradient elasticity across a ferroelectric-to-paraelectric phase transition”, Nano Letters, 24, 10331 (2024)

36. R. Xu, I. Crassee, H. A. Bechtel, Y. Zhou, A. Bercher, L. Korosec, W. Rischau, J. Teyssier, K. J. Crust, Y. Lee, S. N. Gilbert Corder, J. Li, J. A. Dionne, H. Y. Hwang, A. B. Kuzmenko, and Y. Liu, “Highly confined epsilon-near-zero and surface-phonon polaritons in SrTiO₃ membranes”, Nature Communications,15, 4743 (2024)

2023

35. Y. T. Shao, Z. Hong, S. Das, R. Xu, S. Chandrika, L. -Q. Chen, H. Y. Hwang, J. Junquera, L. W. Martin, R. Ramesh, D. Muller, “Emergent chirality in a polar meron to skyrmion phase transition”, Nature Communications, 14, 1355 (2023)

34. R. Xu*, K. J. Crust*, V. Harbola*, R. Arras, K. Y. Patel, S. Prosandeev, H. Cao, Y. T. Shao, P. Behera, L. Caretta, W. J. Kim, A. Khandelwal, M. Acharya, M. M. Wang, Y. Liu, E. S. Barnard, A. Raja, L. W. Martin, X. W. Gu, H. Zhou, R. Ramesh, D. A. Muller, L. Bellaiche, H. Y. Hwang, “Size-induced ferroelectricity in antiferroelectric oxide membranes”, Advanced Materials, 2210562 (2023)

2021

33. T. N. M. Nguyen, Y. Guo, S. Qin. R. Xu, J. C. Agar, “Symmetry-aware recursive image similarity exploration for materials microscopy”, npj Computational Materials 7, 166 (2021)
32. V. Harbola, R. Xu, S. Crossley, P. Singh, H. Y. Hwang, “Fracture and fatigue of thin crystalline SrTiO3 membranes”, Applied Physics Letters 119, 053102 (2021)

2020

31. D. Pesquera, E. Parsonnet, A. Qualls, R. Xu, A. Gubser, J. Kim, Y. Jiang, G. Velarde, Y. -L. Huang, H. Y. Hwang, R. Ramesh, L. W. Martin, “Beyond substrates: Strain engineering of ferroelectric membranes”, Advanced Materials 32, 2003780 (2020)
30. R. Xu*, J. Huang, E. Barnard, S. S. Hong, P. Singh, E. Wong, T. Jansen, V. Harbola, B. Y. Wang, S. Crossley, D. Lu, S. Liu, H. Y. Hwang*, “Strain-induced room-temperature ferroelectricity in SrTiO3 membranes”, Nature Communications 11, 3141 (2020)
29. H. Taz, B. Prasad, Y. -L. Huang, Z. H. Chen, S. -L. Hsu, R. Xu, V. Thakare, T. Sakthivel, C. Liu, C. Henri-Lambert, M. Hettick, R. Mukherjee, S. Seal, L. W. Martin, A. Javey, G. Duscher, R. Ramesh, R. Kalyanaraman, “Integration of amorphous ferromagnetic oxides with multiferroic materials for room temperature magnetoelectric spintronics”, Scientific Reports 10, 3583 (2020)

2019

28. R. Gao, A. Jain, S. Pandya, Y. Dong, Y. Yuan, H. Zhou, L. Dedon, V. Thoreton, S. Saremi, R. Xu, A. Luo, T. Chen, V. Gopalan, E. Ertekin J. Kliner, T. Ishihara, N. Perry, D. Trinkle, L. W. Martin, “Designing optimal perovskite structure for high ionic conduction”, Advanced Materials 32, 1905178 (2019)
27. X. Lu, Z. Chen, Y. Cao, Y. Tang, R. Xu, S. Saremi, Z. Zhang, Y. Dong, S. Das, H. Zhang, L. Zheng, W. Lv, L. Chen, W. Cao, H. Li, L. W. Martin, “Mechanical-force-induced non-local collective ferroelastic switching in epitaxial lead-titanate thin films”, Nature Communications 10, 3951 (2019)
26. D. Lu, S. Crossley, R. Xu, Y. Hikita, H. Y. Hwang, “Freestanding oxide ferroelectric tunnel junction memories transferred onto silicon”, Nano Letters 19, 3999 (2019)
25. R. Xu, S. Liu, S. Saremi, R. Gao, H. Lu, J. J. Wang, Z. J. Hong, A. Ghosh, S. Pandya, E. Bonturim, Z. Chen, L. Q. Chen, A. M. Rappe, L. W. Martin, “Kinetic control of tunable, multi-state switching in ferroelectric thin films”, Nature Communications 10, 1282 (2019)

2018

24. S. Pandya, G. A. Velarde, R. Gao, A. S. Everhardt, J. D. Wilbur, R. Xu, J. T. Maher, J. C. Agar, C. Dames, L. W. Martin, “Understanding the role of ferroelastic domains on the pyroelectric and electrocaloric effects in ferroelectric thin films”, Advanced Materials 31, 1803312 (2018)
23. A. Dasgupta, S. Saremi, R. Xu, L. Dedon, S. Pandya, A. R. Damodaran, L. W. Martin, “Non-stoichiometry, structure, and properties of Ba1-xTiO3 thin films”, Journal of Materials Chemistry C 6, 10751 (2018)
22. S. Saremi, R. Xu, F. Allen, J. Maher, J. C. Agar, R. Gao, P. Hosemann, L. W. Martin, “Local control of defects and switching properties in ferroelectric thin films”, Physical Review Materials 2, 084414 (2018)
21. R. Xu, R. Gao, S. Saremi, S. E. Reyes-Lillo, Y. Dong, Y. Qi, H. Lu, Z. Chen, X. Lu, H. Zhou, J. B. Neaton, L. W. Martin, “Reducing coercive-field scaling in ferroelectric thin films via orientation control”, ACS Nano 12, 4736 (2018)
20. A. I. Khan, M. Hoffmann, K. Chatterjee, Z. Lu, R. Xu, C. Serrao, S. Smith, L. W. Martin, C. C. Hu, R. Ramesh, S. Salahuddin, “Dynamic voltage amplification induced by ferroelectric negative capacitance”, Applied Physics Letters 111, 253501 (2018)

2017

19. S. Saremi, R. Xu, L. R. Dedon, R. Gao, L. W. Martin, “Electronic transport and ferroelectric switching in ion-bombarded, defect-engineered BiFeO3 ­thin films”, Advanced Materials Interfaces 5, 1700991 (2017)
18. Z. Chen, Z. Chen, Z. Liu, M. E. Holtz, C. Li, X. R. Wang, W. Lu, M. Motapothula, L. S. Fan, L. R. Dedon, C. Frederick, R. Xu, R. Gao, A. T. N’Diaye, E. Arenholz, J. A. Mundy, T. Venkatesan­, D. A. Muller, L.-W. Wang, J. Liu, L. W. Martin, “Electronic reconstruction induced ferromagnetism in a polar antiferromagnetic insulator”, Physical Review Letters 119, 156801 (2017)
17. A. R. Damodaran, S. Pandya, J. C. Agar, Y. Cao, R. Vasudevan, R. Xu, S. Saremi, Q. Li, J. Kim, L. R. Dedon, T. Angsten, N. Balke, S. Jesse, M. D. Asta, S. Kalinin, L. W. Martin, “Three-state ferroelastic switching and large electromechanical responses in PbTiO3 thin films”, Advanced Materials 29, 1702069 (2017)
16. R. Gao, S. E. Reyes-Lillo, R. Xu, A. Dasgupta, Y. Dong, L. R. Dedon, J. Kim, S. Saremi, Z. Chen, C. R. Serrao, H. Zhou, J. B. Neaton, L. W. Martin, “Ferroelectricity in Pb1+δZrO3 thin films”, Chemistry of Materials 29, 6544 (2017)
15. S. P. Rogers, R. Xu, S. Pandya, L. W. Martin, M. Shim, “Slow conductance relaxation in graphene-ferroelectric field-effect transistors”, The Journal of Physical Chemistry C ­­121, 7542 (2017)

2016

14. S. Saremi, R. Xu, L. R. Dedon, J. M. Mundy, S. -L. Hsu, Z. H. Chen, A. R. Damodaran, S. P. Chapman, J. T. Evans, L. W. Martin, “Enhanced electrical resistivity and properties via ion bombardment of ferroelectric thin films”, Advanced Materials 28, 10750 (2016)
13. H. Lu, B. Wang, T. Li, A. Lipatov, H. Lee, A. Rajapitamahuni, R. Xu, X. Hong, B. Noheda, L. W. Martin, C. -B. Eom, L. -Q. Chen, A. Sinitskii, A. Gruverman, “Domain engineering in ferroelectric capacitors with graphene electrodes”, Nano Letters 16, 6460 (2016)
12. Z. H. Chen, X. Wang, Y. Qi, S. Yang, J. A. N. T. Soares, B. A. Apgar, R. Gao, R. Xu, Y. Lee, X. Zhang, J. Yao, L. W. Martin, “Self-Assembled, Tunable metamaterials via spinodal decomposition”, ACS Nano 10, 10237 (2016)
11. J. C. Agar, S. Pandya, R. Xu, A. Yadav, Z. Liu, T. Angsten, S. Saremi, M. Asta, R. Ramamoorthy, L. W. Martin, “Frontiers in strain-engineered multifunctional ferroic materials”, MRS Communications 6, 151 (2016)
10. S. Pandya, A. R. Damodaran, R. Xu, J. C. Agar, L. W. Martin, “Strain-induced growth instabilities and surface patterning in perovskite thin films”, Scientific Reports 6, 26075 (2016)
9. J. H. Hinnefeld, R. Xu, S. Rogers, S. Pandya, M. Shim, L. W. Martin, N. Mason, “Single gate P-N junctions in graphene-ferroelectric devices”, Applied Physics Letters 108, 203109 (2016)
8. A. R. Damodaran, J. C. Agar, S. Pandya, Z. Chen, L. Dedon, R. Xu, B. Apgar, S. Saremi, L. W. Martin, “New modalities of strain-control of ferroelectric thin films”, Journal of Physics: Condensed Matter 28, 263001 (2016)
7. M. A. Islam, D. Saldana-Greco, Z. Gu, F. Wang, E. Breckenfeld, Q. Lei, R. Xu, C. J. Hawley, X. X. Xi, L. W. Martin, A. M. Rappe, J. E. Spanier, “Chemically-switchable ultraviolet luminescence from interfacial two-dimensional electron gas”, Nano Letters 16, 681 (2016)

2015

6. R. Xu, J. Zhang, Z. H. Chen, L. W. Martin, “Orientation-dependent structural phase diagrams and dielectric properties of PbZr1-xTixO3 polydomain thin films”, Physical Review B 91, 144106 (2015)

5. R. Xu, S. Liu, J. Karthik, A. R. Damodaran, I. Grinberg, A. M. Rappe, L. W. Martin, “Ferroelectric polarization reversal via successive ferroelastic transitions”, Nature Materials 14, 79 (2015)

2014

4. R. Xu, J. Karthik, A. R. Damodaran, L. W. Martin, “Stationary domain wall contribution to enhanced ferroelectric susceptibility”, Nature Communications 5, 3120 (2014)
3. Z. H. Chen, A. R. Damodaran, R. Xu, S. Lee, L. W. Martin, “Effect of “symmetry mismatch” on the domain structure of rhombohedral BiFeO3 ­thin films”, Applied Physics Letters 104, 182908 (2014)
2. J. Zhang, R. Xu, A. R. Damodaran, Z. H. Chen, L. W. Martin, “Understanding order in compositionally graded ferroelectrics: flexoelectricity, gradient, and depolarization field effects”, Physical Review B 89, 224101 (2014)

2013

1. C. Baeumer, S. P. Rogers, R. Xu, L. W. Martin, M. Shim, “Tunable carrier type and density in graphene/PbZr0.2Ti0.8O3 hybrid structures through ferroelectric switching”, Nano Letters 13, 1693 (2013)