Our current research focuses on the physics of oxide heterostructures and their applications in photonic based quantum computing and neuromorphic computing. On the theoretical side of things, we work on the quantum theory of real materials. Experimentally, we specialize in film growth techniques such as molecular beam epitaxy (MBE) and RF magnetron sputtering and film characterization methods such as reflection high-energy electron diffraction (RHEED), x-ray photoelectron spectroscopy (XPS), and x-ray diffraction (XRD). The complex nature of the problems we research often requires high performance computing, most of which is done at the Texas Advanced Computing Center (TACC), film growth, which is done in our state of the art MBE Lab, and film characterization, which is done in our lab and at the Texas Materials Institute.
Most Recent Publications
2025
- A. Raju, D. Hungund, D. Krueger, Z. Dong, Z. Sakotic, A. B. Posadas, A. A. Demkov, and D. Wasserman, High-Q Monolithic Ring Resonators in Low-Loss Barium Titanate on Silicon, Laser Photonics Rev. 2025, 2402086 (2025). (Access paper)
- H. Jin, S. Jang, A. B. Posadas, and A. A. Demkov, Asymmetric metallic quantum well Al 2 O 3 − Al − Si, Phys. Rev. Materials 9, 066001 (2025). (Access paper)
- H. Wu et al., Defect enhancement of Er emission in single crystal Er2O3, Applied Physics Letters 126, 231102 (2025). (Access paper)
- H. Kim, S. Mathews, J. Tischler, A. B. Posadas, A. A. Demkov, and A. Piqué, Crystal domain orientation control of epitaxial BaTiO3 films integrated on silicon for large electro-optic response, Applied Physics Letters 127, 051102 (2025). (Access paper)
- M. Reynaud, M. Waqar, C. Du, A. B. Posadas, X. Pan, and A. A. Demkov, Enhancement of electro-optic response in BaTiO3 films integrated on Si via heating and cooling rate control, Commun Mater 6, 176 (2025). (Access paper)
2024
- S. Apte and A. A Demkov, “Linear electro-optic effect in strontium barium niobate:A first principles study,” J. Appl. Phys. 135, 084102 (2024) (Access paper)
- I. Kim and A. A Demkov, “Linear electro-optic effect in trigonal LiNbO3: A first-principles study,” Phys. Rev. Materials 8, 025202 (2024) (Access paper)
- Adam Dodson, Hongrui Wu, Anuruddh Rai, Sohm Apte, Andrew O’Hara, Benjamin Lawrie, Yongqiang Wang, Akira Ueda, Halina Krzyżanowska, Michael Titze, Jimmy Davidson, Anthony Hmelo, Agham B Posadas, Alexander A Demkov, Sokrates T Pantelides, Leonard C Feldman and Norman H Tolk, “Phonon-mediated temperature dependence of Er3+ optical transitions in Er2O3,” Commun. Phys. 7, 69 (2024) (Access paper)
- A. A. Demkov and A. B. Posadas, Ferroelectric BaTiO3 for Electro-Optic Modulators in Si Photonics, IEEE Journal of Selected Topics in Quantum Electronics 30, 1 (2024).(Access paper)
- A. Christensen, M. Reynaud, A. B. Posadas, X. Zhan, J. H. Warner, and A. A. Demkov, Electro-optic effect in thin film strontium barium niobate (SBN) grown by RF magnetron sputtering on SrTiO3 substrates, Journal of Applied Physics 136, 013102 (2024).(Access paper)
- S. Apte and A. A. Demkov, Phase transitions and Raman effect in E r 2 O 3 from first principles, Phys. Rev. Materials 8, 116202 (2024).(Access paper)