Research Interests

My research interests span two interrelated areas in experimental condensed matter physics: (1) depth-resolved x-ray spectroscopic and scattering probes of electronic structure and (2) femtosecond electronic structure and spin dynamics. In particular, my research group is focusing on the development of new static and time-resolved synchrotron and FEL-based x-ray techniques and applying these techniques to depth-resolved studies of novel materials, buried interfaces, and multilayer structures.

Recent Academic Distinctions

2021   Humboldt Research Fellowship, Alexander von Humboldt Foundation
2018   DOE Early Career Award, U.S. Department of Energy
2015   ARO Young Investigator Program (YIP) Award, U.S. Army Research Office
2013   Young Scientist Award, SPring-8 User Community, Japan

Key Publications

J. R. Paudel, M. Terilli, T.-C. Wu, J. D. Grassi, A. M. Derrico, R. K. Sah, M. Kareev, F. Wen, C. Klewe, P. Shafer, A. Gloskovskii, C. Schlueter, V. N. Strocov, J. Chakhalian, and A. X. Gray, Direct experimental evidence of tunable charge transfer at the LaNiO3/CaMnO3 ferromagnetic interface, Phys. Rev. B 108, 054441 (2023). [link]

C.-T. Kuo, G. Conti, J. E. Rault, C. M. Schneider, S. Nemsak, and A. X. Gray, Emergent phenomena at oxide interfaces studied with standing-wave photoelectron spectroscopy, J. Vac. Sci. Technol. A 40, 020801 (2022). [link]

A. Arab, X. Liu, O. Köksal, W. Yang, R. U. Chandrasena, S. Middey, M. Kareev, S. Kumar, M.-A. Husanu, Z. Yang, L. Gu, V. N. Strocov, T.-L. Lee, J. Minar, R. Pentcheva, J. Chakhalian, and A. X. Gray, Electronic structure of a graphene-like artificial crystal of NdNiO3, Nano Lett. 19, 8311 (2019). [link]

W. Yang, R. U. Chandrasena, M. Gu, R. M. S. dos Reis, E. J. Moon, Arian Arab, M.-A. Husanu, J. Ciston, V. N. Strocov, J. M. Rondinelli, S. J. May, and A. X. Gray, Probing single unit-cell resolved electronic structure modulations in oxide superlattices with standing-wave photoemission, Phys. Rev. B 100, 125119 (2019). [link]

R. U. Chandrasena, C. L. Flint, W. Yang, A. Arab, S. Nemšák, M. Gehlmann, V. B. Özdöl, F. Bisti, K. D. Wijesekara, J. Meyer-Ilse, E. Gullikson, E. Arenholz, J. Ciston, C. M. Schneider, V. N. Strocov, Y. Suzuki, and A. X. Gray, Depth-resolved charge reconstruction at the LaNiO3/CaMnO3 interface, Phys. Rev. B 98, 155103 (2018). [link]

A. X. Gray et al., Ultrafast THz Field Control of Electronic and Structural Interactions in Vanadium Dioxide, Phys. Rev. B 98, 045104 (2018). [link]

M. Golalikhani, Q. Lei, R. U. Chandrasena, L. Kasaei, H. Park, J. Bai, P. Orgiani, J. Ciston, G. Sterbinsky, D. A. Arena, P. Shafer, E. Arenholz, B. Davidson, A. J. Millis, A. X. Gray, and X. X. Xi, Nature of the metal-insulator transition in few-unit-cells-thick LaNiO3 films, Nature Comm. 9, 2206 (2018). [link]

R. U. Chandrasena, W. Yang, Q. Y. Lei, M. U. Delgado-Jaime, K. Wijesekara, M. Golalikhani, B. A. Davidson, E. Arenholz, K. Kobayashi, M. Kobata, F. M. F. de Groot, U. Aschauer, N. A. Spaldin, X. X. Xi, and A. X. Gray, Strain-Engineered Oxygen Vacancies in CaMnO3 Thin Films, Nano Letters 17, 794 (2017). [link]

A. X. Gray et al., Correlation-Driven Insulator-Metal Transition in Near-Ideal Vanadium Dioxide Films, Phys. Rev. Lett. 116, 116403 (2016). [link]

A. X. Gray et al., Probing Bulk Electronic Structure with Hard X-Ray Angle-Resolved Photoemission, Nature Materials 10, 759 (2011). [link]

A. X. Gray et al., Bulk Electronic Structure of the Dilute Ferromagnetic Semiconductor Ga1-xMnxAs through Hard X-ray Angle-Resolved Photoemission, Nature Materials 11, 957 (2012). [link]

A. X. Gray et al., Electronic Structure Changes across the Metamagnetic Transition in FeRh via Hard X-ray Photoemission, Phys. Rev. Lett. 108, 257208 (2012). [link]

N. B. Aetukuri, A. X. Gray et al., Control of the Metal-Insulator Transition in Vanadium Dioxide by Modifying Orbital Occupancy, Nature Physics 9, 661 (2013). [link]

A. X. Gray et al., Momentum-Resolved Electronic Structure at a Buried Interface from Soft X-ray Standing-Wave Angle-Resolved Photoemission, Europhys. Lett. 104, 17004 (2013). [link]

A. X. Gray, Future Directions in Standing-Wave Photoemission, J. Electron Spectrosc. Relat. Phenom. 195, 399 (2014). [link]

A. X. Gray et al., Interface Properties of Magnetic Tunnel Junction LSMO/STO Superlattices Studied by Standing-Wave Excited Photoemission Spectroscopy, Phys. Rev. B 82, 205116 (2010). [link]

A. X. Gray et al., Standing-Wave Excited Soft X-Ray Photoemission Microscopy: Application to Co Microdot Magnetic Arrays, Appl. Phys. Lett. 97, 062503 (2010). [link]

A. M. Kaiser, A. X. Gray et al., Suppression of Near-Interface Electronic States at the Fermi Level of LaNiO3/SrTiO3 Superlattices, Phys. Rev. Lett. 107, 116402 (2011). [link]

S. X-L. Sun, A. P. Kaduwela, A. X. Gray, and C. S. Fadley, Progress Toward Time-Resolved Molecular Imaging: a Theoretical Study of Optimal Parameters in Static Photoelectron Holography, Phys. Rev. A 89, 053415 (2014). [link]