128 citations · 773 across the 32 of their papers we have counts for
32 papers
High Strength Refractory AlHfNbTiV B2 High Entropy Alloys with High Fracture Strains
Jie Qi, Xuesong Fan, Diego Ibarra Hoyos +2
We demonstrate the development of a series of refractory high-entropy alloys containing aluminum AlRHEAs in the ordered BCC-B2 phase by varying the aluminum content within 10 to 25…
Measurement of the Dzyaloshinskii-Moriya Interaction in Mn4N Films that Host Skyrmions
Wei Zhou, Chung Ting Ma, S. Joseph Poon
Mn4N thin film is one of the potential magnetic mediums for spintronic devices due to its ferrimagnetism with low magnetization, large perpendicular magnetic anisotropy (PMA), ther…
Ultrafast Switching in Synthetic Antiferromagnet with Bilayer Rare-Earth Transition-Metal Ferrimagnets
Chung Ting Ma, Wei Zhou, S. Joseph Poon
In spintronics, it is important to be able to manipulate magnetization rapidly and reliably. Several methods can control magnetization, such as by applying current pulses or magnet…
Conventional Half-Heusler Alloys Advance State-of-the-Art Thermoelectric Properties
Mousumi Mitra, Allen Benton, Md Sabbir Akhanda +4
Half-Heusler (HH) phases have garnered much attention as thermally stable and non-toxic thermoelectric materials for power conversion. The most studied alloys to date utilize Hf, Z…
Interfacial Mixing Effect in a Promising Skyrmionic Material: Ferrimagnetic MnN
Chung T. Ma, Wei Zhou, Brian J. Kirby +1
Interfacial mixing of elements is a well-known phenomenon found in thin film deposition. For thin-film magnetic heterostructures, interfacial compositional inhomogeneities can have…
Machine Learning-Based Classification, Interpretation, and Prediction of High-Entropy-Alloy Intermetallic Phases
Jie Qi, Diego Ibarra Hoyos, S. Joseph Poon
The design of high-entropy alloys (HEA) with desired properties is challenging due to their large compositional space. While various machine learning (ML) models can predict specif…
Tunable Magnetic Skyrmions in Ferrimagnetic MnN
Chung T. Ma, Timothy Q. Hartnett, Wei Zhou +2
Thin films of ferrimagnetic MnN are candidate materials to host magnetic skyrmions that have demonstrated thermal stability up to 450C. However, there are no experiment…
Computing and Memory Technologies based on Magnetic Skyrmions
Hamed Vakili, Wei Zhou, Chung T Ma +13
Solitonic magnetic excitations such as domain walls and, specifically, skyrmionics enable the possibility of compact, high density, ultrafast,all-electronic, low-energy devices, wh…
Rare-earth-free ferrimagnetic Mn4N sub-20 nm thin films as high-temperature spintronic material
W. Zhou, C. T. Ma, T. Q. Hartnett +2
Ferrimagnetic alloy thin films that exhibit perpendicular (out-of-plane) magnetic anisotropy (PMA) with low saturation magnetization, such as GdCo and Mn4N, were predicted to be fa…
Navigating the Complex Compositional Landscape of High-Entropy Alloys
Jie Qi, Andrew M. Cheung, S. Joseph Poon
High-entropy alloys, which exist in the high-dimensional composition space, provide enormous unique opportunities for realizing unprecedented structural and functional properties.…
Multi-Principal-Element Approach to High-Performance Thermoelectric Materials
S. Joseph Poon, Jian He
High-entropy alloys are characterized by high configurational entropy. Since the discovery of high-entropy alloys (HEA) in 2004, entropy engineering has provided a promising direct…
Tuning interfacial Dzyaloshinskii-Moriya interactions in thin amorphous ferrimagnetic alloys
Y. Quessab, J. -W. Xu, C. T. Ma +6
Skyrmions can be stabilized in magnetic systems with broken inversion symmetry and chiral interactions, such as Dzyaloshinskii-Moriya interactions (DMI). Further, compensation of m…
Enhanced Figure of Merit in Bismuth-Antimony Fine-Grained Alloys at Cryogenic Temperatures
Sheng Gao, John Gaskins, Xixiao Hu +3
Thermoelectric (TE) materials research plays a vital role in heat-to-electrical energy conversion and refrigeration applications. Bismuth-antimony (Bi-Sb) alloy is a promising mate…
Amorphous Ferrimagnets: an Ideal Host for Ultra-Small Skyrmions at Room Temperature
S. Joseph Poon, Chung Ting Ma
Recently, magnetic skyrmion has emerged as an active topic of fundamental study and applications in magnetic materials research. Magnetic skyrmions are vortex-like spin excitations…
Half-Heusler Compounds: Promising Materials For Mid-To-High Temperature Thermoelectric Conversion
S. Joseph Poon
Half-Heusler compounds (space group Fm3m) has garnered increasing attention in recent years in the thermoelectric community. Three decades ago, refractory RNiSn half-Heusler compou…
High Entropy Alloys Mined From Phase Diagrams
Qi Jie, Andrew Cheung, S. Joseph Poon
High entropy alloys (HEA) show promise as a new type of high-performance structural material. Their vast degrees of freedom provide for extensive opportunities to design alloys wit…
Recent Advances in Thermoelectric Performance of Half-Heusler Compounds
S. Joseph Poon
Half-Heusler phases (space group F43m, C1b) have recently captured much attention as promising thermoelectric materials for heat-to-electric power conversion in the mid-to-high tem…
Skyrmion Formation Induced by Antiferromagnetic-enhanced Interfacial Dzyaloshinskii Moriya Interaction
Marco Chung Ting Ma, Yunkun Xie, Howard Sheng +2
Neél skyrmions originate from interfacial Dzyaloshinskii Moriya interaction (DMI). Recent studies have explored using ferromagnet to host Neél skyrmions for device applications. Ho…
Semi-metals as potential thermoelectric materials: case of HgTe
Maxime Markov, Xixiao Hu, Han-Chun Liu +4
The best thermoelectric materials are believed to be heavily doped semiconductors. The presence of a bandgap is assumed to be essential to achieve large thermoelectric power factor…
Ballistic transport of long wavelength phonons and thermal conductivity accumulation in nanograined silicon-germanium alloys
Long Chen, Jeffrey L. Braun, Brian F. Donovan +2
Computationally efficient modeling of the thermal conductivity of materials is crucial to thorough experimental planning and theoretical understanding of thermal properties. We pre…
High Thermoelectric Figure of Merit by Resonant Dopant in Half-Heusler Alloys
Long Chen, Yamei Liu, Jian He +2
Half-Heusler alloys have been one of the benchmark high temperature thermoelectric materials owing to their thermal stability and promising figure of merit ZT. Simonson et al. earl…
Half Heusler Alloys for Efficient Thermoelectric Power Conversion
L. Chen, X. Zeng, T. M. Tritt +1
Half-Heusler (HH) phases (space group F43m, Clb) are increasingly gaining attention as promising thermoelectric materials in view of their thermal stability, scalability, and envir…
Exchange Bias and Bistable Magneto-Resistance States in Amorphous TbFeCo thin Films
Xiaopu Li, Chung T. Ma, Jiwei Lu +4
Amorphous TbFeCo thin films sputter deposited at room temperature on thermally oxidized Si substrate are found to exhibit strong perpendicular magnetic anisotropy (PMA). Atom probe…
Uncovering High Thermoelectric Figure of Merit in (Hf,Zr)NiSn Half-Heusler Alloys
L. Chen, S. Gao, X. Zeng +3
Half-Heusler alloys (MgAgSb structure) are promising thermoelectric materials. RNiSn half-Heusler phases (R=Hf, Zr, Ti) are the most studied in view of their thermal stability. The…