37 citations · 54 across the 25 of their papers we have counts for
27 papers
Quasicrystalline oxide interfaces by twisting SrTiO3 membranes
Shivasheesh Varshney, Sooho Choo, Huan Liu +34
Quasicrystals reveal that long-range order can exist without translational periodicity, but deterministic routes for designing strongly bonded quasicrystalline interfaces remain un…
Disentangling Strain and Ti3+ Contributions to the Anomalous Hall Effect in Epitaxial RuO2 Films
S. G. Jeong, A. Santhosh, S. Lee +7
The anomalous Hall effect (AHE) reported in epitaxial RuO2/TiO2 has been attributed to a strain-stabilized magnetic state, but strain can be entangled with Ru-Ti intermixing and in…
Light-Driven Ultrafast Control of Time-Reversal Symmetry in SrTiO3
In Hyeok Choi, Sergei Urazhdin, Shivasheesh Varshney +3
Light-driven control of material symmetry enables the engineering of phenomena forbidden in equilibrium. Although electromagnetic fields have been used to break time-reversal symme…
Electron Beam Radiolysis-Assisted Growth of Rutile TiO2 Thin Films
Silu Guo, Nitin Sathish Kumar, Sreejith Nair +3
A new approach for growing crystalline thin films is developed that takes advantage of electron beam radiolysis being a constructive force to rearrange atoms into a crystalline str…
Epitaxial Strain Activates Altermagnetic Spin-Splitting Torques in RuO2(100)
Qi Jia, Seung Gyo Jeong, Seungjun Lee +10
The altermagnetic nature of rutile RuO2 remains under active debate: bulk measurements indicate a nearly nonmagnetic ground state, whereas thin-film studies have reported symmetry-…
Magneto-Optical Detection of Anisotropic Spin Currents in Altermagnetic RuO2
Joongwon Lee, Jeonglyul Kim, Sreejith Nair +9
Altermagnets are a recently identified class of collinear antiferromagnets that host large spin-split electronic bands, offering a promising platform for efficient spin-current gen…
Designing dislocation-driven polar vortex networks in twisted perovskites
William Sandholt, Nicolas Gauquelin, John Mangeri +21
Twisting two atomic layers produces a geometric moire pattern, but bonding-induced interfacial reconstruction fundamentally transforms this into an ordered dislocation network - a…
Strain-Driven Altermagnetic Spin Splitting Effect in RuO
Seungjun Lee, Seung Gyo Jeong, Jian-Ping Wang +2
The non-relativistic spin-momentum locking in altermagnets gives rise to a time-reversal-odd spin Hall effect, known as the altermagnetic spin-splitting effect (ASSE). Although ASS…
Emergence of unconventional magnetic order in strain-engineered RuO2/TiO2 superlattices
Seung Gyo Jeong, Seungjun Lee, Jin Young Oh +8
The spin ordering in RuO2 remains a highly debated topic, owing to its elusive nature, with reports ranging from a nonmagnetic ground state to signatures of unconventional magnetic…
Wafer-scale High-k SrTiO3 Dielectrics with Rational Barrier-layer Design for Low Leakage and High Charge Density
Majid Mohseni, Shivasheesh Varshney, Seung Gyo Jeong +3
High-k oxides such as SrTiO3 promise large capacitance, but their dielectric response is often limited by leakage currents due to reduced bandgaps. We show that introducing a thin…
Understanding Polaronic Transport in Anatase TiO2 Films by Combining Precise Synthesis and First-Principles Many-Body Theory
F. Liu, Z. Yang, Y. Luo +8
In complex oxides, charge carriers often couple strongly with lattice vibrations to form polarons-entangled electron-phonon quasiparticles whose transport properties remain difficu…
Hybrid MBE Route to Adsorption-Controlled Growth of BaTiO3 Membranes with Robust Polarization Switching
S. Choo, S. Varshney, J. Shah +5
Freestanding ferroelectric membranes are promising for flexible electronics, nonvolatile memory, photonics, and spintronics, but their synthesis is challenged by the need for repro…
Strain Engineering of Altermagnetic Symmetry in Epitaxial RuO Films
Johnathas D. S. Forte, Seung Gyo Jeong, Anand Santhosh +3
The magnetic ground state of RuO has been under intense debate. Using first-principles calculations, we show that compressive strain along [001] direction stabilizes an alterma…
Strain-induced Dynamic Spin-Phonon Coupling in Epitaxial RuO2 Films
In Hyeok Choi, Seung Gyo Jeong2, Seung Gyo Jeong +7
Magnetic order parameters in altermagnets can couple to quantized lattice vibration via both piezomagnetic and magnetoelastic effects, leading to the renormalization of phonon disp…
Superconducting Dome in Ionic Liquid Gated Homoepitaxial Strontium Titanate Thin Films
Sushant Padhye, Jin Yue, Shivasheesh Varshney +3
In this work, we patterned a two-dimensional electron gas (2DEG) on the surface of a SrTiO thin film grown homoepitaxially on SrTiO by hybrid molecular beam epitaxy (hMBE).…
Observation of mirror-odd and mirror-even spin texture in ultrathin epitaxially strained RuO2 films
Yichen Zhang, Seung Gyo Jeong, Luca Buiarelli +24
Recently, rutile ruthenium dioxide (RuO) has attracted renewed interest due to expectations of prominent altermagnetic spin splitting. However, accumulating experimental eviden…
Machine Learning-Assisted Nano-imaging and Spectroscopy of Phase Coexistence in a Wide-Bandgap Semiconductor
Alyssa Bragg, Fengdeng Liu, Zhifei Yang +10
Wide bandgap semiconductors with high room temperature mobilities are promising materials for high-power electronics. Stannate films provide wide bandgaps and optical transparency,…
Strain-Stabilized Interfacial Polarization Tunes Work Function Over 1 eV in RuO2/TiO2 Heterostructures
Seung Gyo Jeong, Bonnie Y. X. Lin, Mengru Jin +14
Interfacial polarization-charge accumulation at the heterointerface-is a well-established tool in semiconductors, but its influence in metals remains unexplored. Here, we demonstra…
High-Performance Ultra-Wide-Bandgap CaSnO3 Metal-Oxide-Semiconductor Field-Effect Transistors
Weideng Sun, Junghyun Koo, Donghwan Kim +8
The increasing demand for high-voltage and high-power electronic applications has intensified the search for novel ultrawide bandgap (UWB) semiconductors. Alkaline earth stannates…
Ferroelectric Switching in Hybrid Molecular Beam Epitaxy-Grown BaTiO3 Films
Anusha Kamath Manjeshwar, Zhifei Yang, Chin-Hsiang Liao +4
Molecular beam epitaxy (MBE) is a promising synthesis technique for both heterostructure growth and epitaxial integration of ferroelectric BaTiO3. However, a direct measurement of…
Interfacial strong coupling and negative dispersion of propagating polaritons in freestanding oxide membranes
Brayden Lukaskawcez, Shivasheesh Varshney, Sooho Choo +12
Membranes of complex oxides like perovskite SrTiO3 extend the multi-functional promise of oxide electronics into the nanoscale regime of two-dimensional materials. Here we demonstr…
Intrinsic vs. Extrinsic Magnetic Transitions in Sr3Ru2O7 films
R. Choudhary, A. Rajapitamahuni, S. Guo +4
In scientific research, both positive and negative results play crucial role in advancing the field. Negative results provide valuable insights that can guide future experiments an…
Anisotropic Strain Relaxation-Induced Directional Ultrafast Carrier Dynamics in RuO2 Films
S. G. Jeong, I. H. Choi, S. Lee +9
Ultrafast light-matter interactions inspire potential functionalities in picosecond optoelectronic applications. However, achieving directional carrier dynamics in metals remains c…
Absence of two-phonon quasi-elastic scattering in the normal state of doped--SrTiO by THz pump-probe spectroscopy
K. Santhosh Kumar, David Barbalas, Rishi Bhandia +4
Multi-pulse nonlinear THz spectroscopies enable a new understanding of interacting metallic systems via their sensitivity to novel correlation functions. Here, we investigated the…