https://scholar.dgist.ac.kr/handle/20.500.11750/800 2026-08-14T10:24:07Z https://scholar.dgist.ac.kr/handle/20.500.11750/60590 Title: A comparative synthesis study of α-MnTe across solid-state, Arc-melting, and Te-flux routes Author(s): Kim, Bomin; Jeong, Yunseong; Baek, Wonjung; Kim, Hobyeong; Rhee, Taeseong; Cho, Beopgil; Choi, Woo-Jae; Ha, Jae-Hyun; Park, Jaemun; Hong, Jung-Il; Kwon, Yong Seung; Seo, Jungpil; Park, Keeseong Abstract: Although alpha-MnTe has attracted renewed interest in both thermoelectric and altermagnetic contexts, direct comparisons of practically accessible synthesis routes within a common experimental framework remain limited. Here, we compare conventional solid-state reaction, arc melting and Te self-flux growth methods under a common framework of composition control and thermal history. Within the explored conditions, the phase outcome depends not only on the nominal starting composition but also on route-dependent synthesis environments, including volatilization in sealed ampoules, repeated remelting and rapid quenching in arc melting, and crystal-flux interfacial segregation in Te self-flux growth. In the solid-state route, slow heating with a slightly Mn-rich starting composition was associated with reduced MnTe2 and alpha-MnTe-dominant products. Arc melting yielded alpha-MnTe-dominant products without post-annealing, accompanied by dendritic-like microstructures. Te self-flux growth yielded single crystals, although a minor MnTe2-rich interfacial or surface layer often remained. While the present dataset does not define a rigorous phase boundary or a definitive mechanistic model, it provides a systematic comparative framework for route-dependent phase outcomes and impurity persistence in alpha-MnTe synthesis. 2026-07-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/60502 Title: A comparative synthesis study of α-MnTe across solid-state, Arc-melting, and Te-flux routes Author(s): Kim, Bomin; Jeong, Yunseong; Baek, Wonjung; Kim, Hobyeong; Rhee, Taeseong; Cho, Beopgil; Choi, Woo-Jae; Ha, Jae-Hyun; Park, Jaemun; Hong, Jung-Il; Kwon, Yong Seung; Seo, Jungpil; Park, Keeseong Abstract: Although alpha-MnTe has attracted renewed interest in both thermoelectric and altermagnetic contexts, direct comparisons of practically accessible synthesis routes within a common experimental framework remain limited. Here, we compare conventional solid-state reaction, arc melting and Te self-flux growth methods under a common framework of composition control and thermal history. Within the explored conditions, the phase outcome depends not only on the nominal starting composition but also on route-dependent synthesis environments, including volatilization in sealed ampoules, repeated remelting and rapid quenching in arc melting, and crystal-flux interfacial segregation in Te self-flux growth. In the solid-state route, slow heating with a slightly Mn-rich starting composition was associated with reduced MnTe2 and alpha-MnTe-dominant products. Arc melting yielded alpha-MnTe-dominant products without post-annealing, accompanied by dendritic-like microstructures. Te self-flux growth yielded single crystals, although a minor MnTe2-rich interfacial or surface layer often remained. While the present dataset does not define a rigorous phase boundary or a definitive mechanistic model, it provides a systematic comparative framework for route-dependent phase outcomes and impurity persistence in alpha-MnTe synthesis. 2026-07-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/60420 Title: Quantized Conductance through Surface States in High Quality Three-Dimensional Dirac Semimetal Cd3As2 Nanowire/Nanoribbon p-n Junctions Author(s): An, Sungjin; Siu, Zhuo Bin; Kaladzhyan, Vardan; Bardarson, Jens H.; Lee, Sunghun; Lee, Myoung-Jae; Park, Kidong; Park, Jeunghee; Jalil, Mansoor B. A.; Seo, Jungpil; Jung, Minkyung Abstract: We report the observation of quantized conductance in high-mobility three-dimensional Dirac semimetal Cd3As2 nanowire and nanoribbon p-n junctions. By employing suspended device geometries with dual local gates, we form tunable p-n junctions and realize ballistic transport across sub-micron channel lengths. In a wide nanoribbon device with a channel width of similar to 330 nm, conductance plateaus appear at integer multiples of 2e(2)/h in the n-n regime under high magnetic fields. Numerical simulations suggest that these features represent unresolved spin split subbands due to the smaller subband spacing in wider channels and support the interpretation that the observed quantization may originate from surface-state-dominated conduction. In contrast, narrower nanoribbons and nanowires exhibit conductance steps of 1e(2)/h, demonstrating spin-resolved subbands likely due to enhanced confinement effects. From spin-resolved subband spectroscopy, we extract an effective Land & eacute; g-factor of similar to 43 for the first subband in the bulk gap, establishing these nanostructures as a prospective platform for fault-tolerant quantum electronics. 2026-05-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/59294 Title: Radio-Frequency Detection of Fabry–Pérot Interference and Quantum Capacitance in Long-Channel Three-Dimensional Dirac Semimetal Cd3As2Nanowires Author(s): An, Sung Jin; Kim, Jisu; Jung, Myung-chul; Park, Kidong; Park, Jeunghee; Shim, Seung-bo; Kim, Hakseong; Siu, Zhuo Bin; Jalil, Mansoor B.A.; Schönenberger, Christian; Myoung, Nojoon; Seo, Jungpil; Jung, Minkyung Abstract: We demonstrate phase-coherent transport in suspended long-channel Cd3As2 nanowire devices using both direct current (DC) transport and radiofrequency (RF) reflectometry measurements. By integrating Cd3As2 nanowires with on-chip superconducting LC resonators, we achieve sensitive detection of both resistance and quantum capacitance variations. In a long-channel device (L ≈ 1.8 μm), clear Fabry–Pérot (FP) interference patterns are observed in both DC and RF measurements, providing strong evidence for ballistic electron transport. RF reflectometry reveals gate-dependent modulations of the resonance frequency arising from quantum capacitance oscillations induced by changes in the density of states and FP interference. These oscillations exhibit a quasi-periodic structure that closely correlates with the FP patterns in DC transport measurements. In another device of a Cd3As2 nanowire Josephson junction (L ≈ 730 nm, superconducting Al contacts), FP interference patterns are too weak to be resolved in DC conductance but are detectable using RF reflectometry. These results demonstrate the high quality of our Cd3As2 nanowires and the versatility of RF reflectometry, establishing their potential for applications in topological quantum devices such as Andreev qubits or gatemon architectures. 2025-09-30T15:00:00Z