Publications — El Baggari Lab

Helium-Cooled Cryogenic STEM Imaging and Ptychography for Atomic-Scale Study of Low-Temperature Phases

Noah Schnitzer, Mariana Palos, Geri Topore, Nishkarsh Agarwal, Maya Gates, Yaqi Li, Robert Hovden, Ismail El Baggari, Suk Hyun Sung, Michele Shelly Conroy

arXiv:2603.10892 (2026) — preprint

Melting of Charge Density Waves in Low Dimensions

Jeremy M. Shen, Alex Stangel, Suk Hyun Sung, Ismail El Baggari, Kai Sun, Robert Hovden

Matter (2026)

Topochemical Oxidation of Ruddlesden–Popper Nickelates Reveals Distinct Structural Family: Oxygen-Intercalated Layered Perovskites

Dan Ferenc Segedin, Jinkwon Kim, Harrison LaBollita, Nicole K. Taylor, Kyeong-Yoon Baek, Suk Hyun Sung, Ari B. Turkiewicz, Grace A. Pan, Abigail Y. Jiang, Maria Bambrick-Santoyo, Tobias Schwaigert, Casey K. Kim, Anirudh Tenneti, Alexander J. Grutter, Shin Muramoto, Alpha T. N'Diaye, Ismail El Baggari, Donald A. Walko, Charles M. Brooks, Antia S. Botana, Darrell G. Schlom, Hua Zhou, Julia A. Mundy

Journal of the American Chemical Society 148, 6, 5873–5880 (2026)

Unconventional polaronic ground state in superconducting LiTi₂O₄

Zubia Hasan, Grace A. Pan, Harrison LaBollita, Austin Kaczmarek, Suk Hyun Sung, Shekhar Sharma, Purnima P. Balakrishnan, Edward Mercer, Vivek Bhartiya, Alpha T. N'Diaye, Zaher Salman, Thomas Prokscha, Andreas Suter, Alexander J. Grutter, Mirian Garcia-Fernandez, Ke-Jin Zhou, Jonathan Pelliciari, Valentina Bisogni, Ismail El Baggari, Darrell G. Schlom, Matthew R. Barone, Charles M. Brooks, Katja C. Nowack, Antia S. Botana, Brendan D. Faeth, Alberto de la Torre, Julia A. Mundy

Nature Communications 17, 1303 (2026)

Mesoscopic Helices of Polar Domains in a Quadruple Perovskite

Yang Zhang, Mingyu Xu, Jie Li, Suk Hyun Sung, Sang-Wook Cheong, Weiwei Xie, Ismail El Baggari

arXiv:2506.03048 (2025) — preprint

Liquid Helium Cryogenic TEM below 1 Å

Suk Hyun Sung, Maya Gates, Nishkarsh Agarwal, Yang Zhang, William Millsaps, Miti Shah, Emily Rennich, Cong Li, Pu Yu, Miaofang Chi, Benjamin H. Savitzky, Ismail El Baggari, Robert Hovden

arXiv:2509.12475 (2025) — preprint

Nanoscale Polar Landscapes in Quantum Paraelectric SrTiO₃

Yang Zhang, Suk Hyun Sung, Nishkarsh Agarwal, Maya Gates, Cong Li, Pu Yu, Robert Hovden, Ismail El Baggari

arXiv:2509.24969 (2025) — preprint

Real-space visualization of order-disorder transition in BaTiO₃

Yang Zhang, Xiaoming Shi, Suk Hyun Sung, Cong Li, Houbing Huang, Pu Yu, Ismail El Baggari

Science Advances 11, 36 (2025)

Inverse Melting of Polar Order in Chemically Substituted BaTiO₃

Yang Zhang, Suk Hyun Sung, Colin B. Clement, Sang-Wook Cheong, Ismail El Baggari

Physical Review Letters 134, 256801 (2025)

Ultra-Cold Cryogenic TEM with Liquid Helium and High Stability

Emily Rennich*, Suk Hyun Sung*, Nishkarsh Agarwal, Maya Gates, Robert Kerns, Robert Hovden, Ismail El Baggari

Proceedings of the National Academy of Sciences 122, 36 (2025)

Atomic-Scale Tracking of Topological Defect Motion and Incommensurate Charge Order Melting

Noah Schnitzer, Berit H. Goodge, Gregory Powers, Jaewook Kim, Sang-Wook Cheong, Ismail El Baggari, Lena F. Kourkoutis

Physical Review X 15, 011007 (2025)

Effect of Stoichiometry on the Structure and Polarization of BaTiO₃

A. E. Cavanagh, L. B. Little, D. R. Barton, N. K. Taylor, H.-Y. G. Lin, A. T. N'Diaye, J. A. Gardener, C. M. Brooks, Ismail El Baggari, R. M. Westervelt, J. A. Mundy

Advanced Optical Materials 13, 2501037 (2025)

Defect Engineering in Epitaxial Thin Films of the Pyrochlore Frustrated Magnet Tb₂Ti₂O₇

Anderson, Margaret; El Baggari, Ismail; Brooks, Charles; Powell, Troy; Lygouras, Chris; N'Diaye, Alpha; Koohpayeh, Seyed; Nordlander, Johanna; Mundy, Julia

Chemistry of Materials 36, 2325 (2024)

Endotaxial Stabilization of 2D Charge Density Waves with Long-range Order

Suk Hyun Sung, Nishkarsh Agarwal, Ismail El Baggari, Yin Min Goh, Pat Kezer, Noah Schnitzer, Lena F. Kourkoutis, John T Heron, Kai Sun, Robert Hovden

Nature Communications 15, 1403 (2024)

Limits to the strain engineering of layered square-planar nickelate thin films

Dan Ferenc Segedin*, Berit H. Goodge*, Grace A. Pan, Hesham El-Sherif, Qi Song, Erin E. Fleck, Nicole Taylor, Spencer Doyle, Jarad A. Mason, Hanjong Paik, Ismail El Baggari, Lena F. Kourkoutis, Charles M. Brooks, Julia A. Mundy

Nature Communications 14, 1 (2023)

Antiferromagnetic metal phase in an electron-doped rare-earth nickelate

Qi Song, Spencer Doyle, Grace Pan, Ismail El Baggari, Dan Ferenc Segedin, Denisse Cordova Carrizales, James Ehrets, Zubia Hasan, Hesham El-Sherif, Jyoti Krishna, Chase Hanson, Harrison LaBollita, Aaron Bostwick, Chris Jozwiak, Eli Rotenberg, Alessandra Lanzara, Alpha N'Diaye, Colin Heikes, Yaohua Liu, Hanjong Paik, Charles Brooks, Betül Pamuk, John Heron, Padraic Shafer, William Ratcliff, Antia Botana, Luca Moreschini, Julia A Mundy

Nature Physics 19, 522–528 (2023)

Synthesis and electronic properties of Nd_n+1Ni_nO_3n+1 Ruddlesden-Popper nickelate thin films

G. A. Pan, Q. Song, D. F. Segedin, M. Jung, H. El-Sherif, E. E. Fleck, B. H. Goodge, S. Doyle, D. C. Carrizales, A. T. N'Diaye, P. Shafer, H. Paik, L. F. Kourkoutis, I. El Baggari, A. S. Botana, C. M. Brooks, J. A. Mundy

Physical Review Materials 6, 055003 (2022)

Disentangling Coexisting Structural Order Through Phase Lock-in Analysis of Atomic-Resolution STEM Data

B. H. Goodge, I. El Baggari, S. S Hong, Z. Wang, D. G. Schlom, H. Y. Hwang, L. F. Kourkoutis

Microscopy and Microanalysis 1–8 (2022)

Imaging Atomic-Scale Chemistry from Fused Multi-Modal Electron Microscopy

J. Schwartz, Z. W. Di, Y. Jiang, A. J. F., D. Ha, S. D. Perera, I. El Baggari, R. D. Robinson, J. A. Fessler, C. Ophus, S. Rozeveld, R. Hovden

npj Computational Materials 8, 16 (2022)

Two-dimensional electronic order stabilized in clean polytype heterostructures

S. H. Sung, N. Schnitzer, S. Novakov, I. El Baggari, X. Luo, J. Gim, N. Vu, T. Brintlinger, Y. Sun, K. Sun, L. Zhao, L. F. Kourkoutis, J. T. Heron, R. Hovden

Nature Communications 13, 413 (2022)

Mapping defect relaxation in quantum dot solids upon in situ heating

M. Smeaton, I. El Baggari, D. M. Balazs, T. Hanrath, L. F. Kourkoutis

ACS Nano 15, 1 (2021)

Charge order textures induced by non-linear couplings in a half-doped manganite

I. El Baggari*, D. J. Baek*, M. J. Zachman, D. Liu, Y. Hikita, H. Y. Hwang, E. A. Nowadnick, L. F. Kourkoutis

Nature Communications 12, 3747 (2021)

Direct visualization of trimerized states in 1T′-TaTe₂

I. El Baggari, N. Sivadas, G. M. Stiehl, J. Waelder, D. C. Ralph, C. J. Fennie, L. F. Kourkoutis

Physical Review Letters 125, 165302 (2020)

Layer-dependent spin-orbit torques generated by the centrosymmetric transition metal dichalcogenide β-MoTe₂

G. M. Stiehl, R. Li, V. Gupta, I. El Baggari, S. Jiang, H. Xie, L. F. Kourkoutis, K. F. Mak, J. Shan, R. A. Buhrman, D. C. Ralph

Physical Review B 100, 184402 (2019)

Tunable magnetic transition to a singlet ground state in a 2D Van der Waals layered trimerized Kagomé magnet

C. M. Pasco, I. El Baggari, E. Bianco, L. F. Kourkoutis, T. M. McQueen

ACS Nano 13, 8 (2019)

Current-induced torque with Dresselhaus symmetry due to resistance anisotropy in 2D materials

G. M. Stiehl, D. MacNeill, N. Sivadas, I. El Baggari, M. H. D. Guimarães, N. D. Reynolds, L. F. Kourkoutis, R. A. Buhrman, C. J. Fennie, D. C. Ralph

ACS Nano 13, 2 (2019)

Developments in electron microscopy of exotic states at oxide interfaces: cryogenic imaging and advanced detectors

I. El Baggari and L. F. Kourkoutis

Applied Surface Science 482, 1–93 (2019) — invited review

Nature and evolution of incommensurate charge order in manganites visualized with cryogenic scanning transmission electron microscopy

I. El Baggari, B. H. Savitzky, A. S. Admasu, J. Kim, S. W. Cheong, R. Hovden, L. F. Kourkoutis

Proceedings of the National Academy of Sciences 115(7), 1445–1450 (2018)

Image registration of low signal-to-noise cryo-STEM data

B. H. Savitzky, I. El Baggari, C. B. Clement, E. Waite, B. H. Goodge, D. J. Baek, J. P. Sheckelton, C. Pasco, H. Nair, N. J. Schreiber, J. Hoffman, A. S. Admasu, J. Kim, S. W. Cheong, A. Bhattacharya, D. G. Schlom, T. M. McQueen, R. Hovden, L. F. Kourkoutis

Ultramicroscopy 191, 56–65 (2018)

Bending and breaking of stripes in a charge ordered manganite

B. H. Savitzky*, I. El Baggari*, A. S. Admasu, J. Kim, S. W. Cheong, R. Hovden, L. F. Kourkoutis

Nature Communications 8(1), 1883 (2017)

Atomic lattice disorder in charge-density-wave phases of exfoliated dichalcogenides (1T-TaS₂)

R. Hovden, A. W. Tsen, P. Liu, B. H. Savitzky, I. El Baggari, Y. Liu, W. Lu, Y. Sun, P. Kim, A. N. Pasupathy, L. F. Kourkoutis

Proceedings of the National Academy of Sciences 113, 11420 (2016)