Xiaoyu Yuan
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Xiaoyu Yuan has a total of 47 co-authors. Here are the top co-authors by number of shared publications:
Seongshik Oh
Rutgers, The State University of New Jersey
3 shared publications- Hee Taek Yi
Rutgers, The State University of New Jersey
2 shared publications - Seongshik Oh
Rutgers University
2 shared publications Xiong Yao
Rutgers, The State University of New Jersey
2 shared publications- Xiong Yao
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences 1 , Ningbo 315201
2 shared publications - Akshat Gandhi
Rutgers, The State University of New Jersey
1 shared publication
Latest Publications
- 15 September 2026
- Published by American Physical Society (APS) in Physical Review Materials
- Vol. 10 (9) , 094405
Origins of ferromagnetism in helium-implanted PdCoO 2
Magnetic materials that combine strong spin-orbit coupling with ferromagnetism enable interconversion between charge and spin currents as well as stabilization of exotic spin textures, properties that are critical for advancing next-generation spintronic technologies. The metallic delafossite ${\mathrm{PdCoO}}_{2}$ is a highly conductive, nonmagnetic oxide that resides near a magnetic instability, making it a unique and promising monolithic platform for spin phenomena. Here, we investigate how helium implantation drives ${\mathrm{PdCoO}}_{2}$ into a magnetic state. Through depth-resolved low-energy muon spin relaxation (LE-\ensuremath{\mu}SR) measurements, ion implantation simulations, and first-principles calculations, the defects responsible for the emergent magnetism are identified. While oxygen Frenkel pairs, palladium Frenkel pairs, and interstitial helium contribute weakly, cobalt Frenkel pairs play the dominant role in generating magnetism. In addition, postimplantation annealing reveals distinct thermal windows for defect recombination, confirming the elemental specificity of cation-related defects. These findings establish defect engineering via ion implantation as a powerful route to controllably induce magnetism in ${\mathrm{PdCoO}}_{2}$. The combination of strong spin-orbit coupling, selectively tunable magnetism, and ultrahigh conductivity positions helium-implanted ${\mathrm{PdCoO}}_{2}$ as a unique platform for monolithic spintronic device integration, with implications for low-power magnetic memory and unconventional logic applications.- 15 September 2026
- Published by American Physical Society (APS) in Physical Review Materials
- Vol. 10 (9) , 094405
Origins of ferromagnetism in helium-implanted PdCoO 2
Magnetic materials that combine strong spin-orbit coupling with ferromagnetism enable interconversion between charge and spin currents as well as stabilization of exotic spin textures, properties that are critical for advancing next-generation spintronic technologies. The metallic delafossite ${\mathrm{PdCoO}}_{2}$ is a highly conductive, nonmagnetic oxide that resides near a magnetic instability, making it a unique and promising monolithic platform for spin phenomena. Here, we investigate how helium implantation drives ${\mathrm{PdCoO}}_{2}$ into a magnetic state. Through depth-resolved low-energy muon spin relaxation (LE-\ensuremath{\mu}SR) measurements, ion implantation simulations, and first-principles calculations, the defects responsible for the emergent magnetism are identified. While oxygen Frenkel pairs, palladium Frenkel pairs, and interstitial helium contribute weakly, cobalt Frenkel pairs play the dominant role in generating magnetism. In addition, postimplantation annealing reveals distinct thermal windows for defect recombination, confirming the elemental specificity of cation-related defects. These findings establish defect engineering via ion implantation as a powerful route to controllably induce magnetism in ${\mathrm{PdCoO}}_{2}$. The combination of strong spin-orbit coupling, selectively tunable magnetism, and ultrahigh conductivity positions helium-implanted ${\mathrm{PdCoO}}_{2}$ as a unique platform for monolithic spintronic device integration, with implications for low-power magnetic memory and unconventional logic applications.- Open Access
- 29 May 2026
- Published by American Chemical Society (ACS) in ACS Applied Nano Materials
- Vol. 9 (23) , 10684-10690
Superconducting PdTe Thin Film via Topotactic Transformation, toward Topological Superconductors
Topological superconductors (TSCs) hosting Majorana zero modes (MZMs) offer a pathway to fault-tolerant quantum computation. PdTe is a promising TSC candidate due to its topological surface states and a reasonable superconducting critical temperature of ∼4.5 K. However, it has been challenging to grow PdTe thin films with bulk-like superconducting properties. Here, we show that high-quality, superconducting PdTe thin films can be grown using molecular beam epitaxy (MBE). The films exhibit a sharp superconducting transition (Tonset = 4.43 K with transition width of 0.06 K), comparable to that of bulk crystals. This was made possible via a topotactic transformation from a PdTe2 buffer layer to a PdTe phase by growing Pd on top under Te-deficient conditions. Structural and transport analyses confirm the NiAs-type structure of PdTe as well as its two-dimensional superconducting behavior and excellent air stability. These findings suggest that the MBE-grown PdTe films and their heterostructures are a promising platform for topological superconductivity and Majorana physics.
- 29 May 2026
- Published by American Chemical Society (ACS) in ACS Applied Nano Materials
- Vol. 9 (23) , 10684-10690
Open AccessSuperconducting PdTe Thin Film via Topotactic Transformation, toward Topological Superconductors
Topological superconductors (TSCs) hosting Majorana zero modes (MZMs) offer a pathway to fault-tolerant quantum computation. PdTe is a promising TSC candidate due to its topological surface states and a reasonable superconducting critical temperature of ∼4.5 K. However, it has been challenging to grow PdTe thin films with bulk-like superconducting properties. Here, we show that high-quality, superconducting PdTe thin films can be grown using molecular beam epitaxy (MBE). The films exhibit a sharp superconducting transition (Tonset = 4.43 K with transition width of 0.06 K), comparable to that of bulk crystals. This was made possible via a topotactic transformation from a PdTe2 buffer layer to a PdTe phase by growing Pd on top under Te-deficient conditions. Structural and transport analyses confirm the NiAs-type structure of PdTe as well as its two-dimensional superconducting behavior and excellent air stability. These findings suggest that the MBE-grown PdTe films and their heterostructures are a promising platform for topological superconductivity and Majorana physics.
- Open Access
- 1 January 2025
- Published by AIP Publishing in APL Materials
- Vol. 13 (1)
Mystery of superconductivity in FeTe films and the role of neighboring layers
Since the discovery of superconductivity in the Fe(Te,Se) system, it has been a general consensus that the end member of FeTe is not superconducting. Nonetheless, in recent years, there have been reports of superconducting FeTe films, but the origin of their superconductivity remains mysterious. Here, we provide the first comprehensive review of all the reported FeTe films regarding the relationship between their superconductivity and neighboring layers. Based on this review, we show that telluride neighboring layers are key to superconducting FeTe films. Then, with additional new studies, we show that stoichiometric Te content, which can be readily achieved in FeTe films with the assistance of neighboring telluride layers, might be crucial to stabilizing the superconductivity in this system. This work provides insights into the underlying mechanism behind superconductivity in FeTe films and sheds light on the critical role of neighboring layers and stoichiometry control toward manipulating topological superconductivity in FeTe heterostructures.
- 1 January 2025
- Published by AIP Publishing in APL Materials
- Vol. 13 (1)
Open AccessMystery of superconductivity in FeTe films and the role of neighboring layers
Since the discovery of superconductivity in the Fe(Te,Se) system, it has been a general consensus that the end member of FeTe is not superconducting. Nonetheless, in recent years, there have been reports of superconducting FeTe films, but the origin of their superconductivity remains mysterious. Here, we provide the first comprehensive review of all the reported FeTe films regarding the relationship between their superconductivity and neighboring layers. Based on this review, we show that telluride neighboring layers are key to superconducting FeTe films. Then, with additional new studies, we show that stoichiometric Te content, which can be readily achieved in FeTe films with the assistance of neighboring telluride layers, might be crucial to stabilizing the superconductivity in this system. This work provides insights into the underlying mechanism behind superconductivity in FeTe films and sheds light on the critical role of neighboring layers and stoichiometry control toward manipulating topological superconductivity in FeTe heterostructures.
- 7 June 2024
- Published by American Physical Society (APS) in Physical Review B
- Vol. 109 (24)
Observation of terahertz second harmonic generation from Dirac surface states in the topological insulator- 7 June 2024
- Published by American Physical Society (APS) in Physical Review B
- Vol. 109 (24)
Observation of terahertz second harmonic generation from Dirac surface states in the topological insulator- 14 March 2024
- Published by American Physical Society (APS) in Physical Review B
- Vol. 109 (9) , 094511
Signatures of Majorana bound states in the diffraction patterns of extended superconductor–topological insulator–superconductor Josephson junctions
In an extended superconductor-topological insulator-superconductor (S-TI-S) Josephson junction in a magnetic field, localized Majorana bound states (MBS) are predicted to exist at the cores of Josephson vortices where the local phase difference across the junction is an odd-multiple of . These states contribute a supercurrent with a -periodic current-phase relation (CPR) that adds to the conventional -periodic sinusoidal CPR. In this work, we present a comprehensive experimental study of the critical current vs. applied magnetic field diffraction patterns of lateral Nb--Nb Josephson junctions. We compare our observations to a model of the Josephson dynamics in the S-TI-S junction system to explore what features of MBS are, or are not, exhibited in these junctions. Consistent with the model, we find several distinct deviations from a Fraunhofer diffraction pattern that is expected for a uniform CPR. In particular, we observe abrupt changes in the diffraction pattern at applied magnetic fields in which the current-carrying localized MBS are expected to enter the junction, and a lifting of the odd-numbered nodes consistent with a -periodic component in the CPR. We also see that although the even-numbered nodes often remain fully formed, we sometimes see deviations that are consistent with quasiparticle-induced fluctuations in the parity of the MBS pairs that encode quantum information.- 14 March 2024
- Published by American Physical Society (APS) in Physical Review B
- Vol. 109 (9) , 094511
Signatures of Majorana bound states in the diffraction patterns of extended superconductor–topological insulator–superconductor Josephson junctions
In an extended superconductor-topological insulator-superconductor (S-TI-S) Josephson junction in a magnetic field, localized Majorana bound states (MBS) are predicted to exist at the cores of Josephson vortices where the local phase difference across the junction is an odd-multiple of . These states contribute a supercurrent with a -periodic current-phase relation (CPR) that adds to the conventional -periodic sinusoidal CPR. In this work, we present a comprehensive experimental study of the critical current vs. applied magnetic field diffraction patterns of lateral Nb--Nb Josephson junctions. We compare our observations to a model of the Josephson dynamics in the S-TI-S junction system to explore what features of MBS are, or are not, exhibited in these junctions. Consistent with the model, we find several distinct deviations from a Fraunhofer diffraction pattern that is expected for a uniform CPR. In particular, we observe abrupt changes in the diffraction pattern at applied magnetic fields in which the current-carrying localized MBS are expected to enter the junction, and a lifting of the odd-numbered nodes consistent with a -periodic component in the CPR. We also see that although the even-numbered nodes often remain fully formed, we sometimes see deviations that are consistent with quasiparticle-induced fluctuations in the parity of the MBS pairs that encode quantum information.