Article
Chemistry, Multidisciplinary
Raitis Sondors, Kiryl Niherysh, Jana Andzane, Xavier Palermo, Thilo Bauch, Floriana Lombardi, Donats Erts
Summary: A catalyst-free physical vapor deposition method was optimized by adjusting source material pressure and evaporation time to obtain reliable freestanding nanoribbons with thicknesses below 15 nm. The optimum synthesis conditions were determined for increased yield of ultrathin Bi2Se3 nanoribbons with thicknesses of 8-15 nm. The physical and electrical characterization of the synthesized nanoribbons revealed no degradation of properties and the absence of trivial bulk charge carriers.
Article
Chemistry, Multidisciplinary
Gunta Kunakova, Edijs Kauranens, Kiryl Niherysh, Mikhael Bechelany, Krisjanis Smits, Gatis Mozolevskis, Thilo Bauch, Floriana Lombardi, Donats Erts
Summary: Researchers investigated all-around ZnO-encapsulated Bi2Se3 nanoribbons and found them to have improved charge transport characteristics compared to nanoribbons grown on SiO2 substrates, due to reduced carrier densities at the nanoribbon/substrate interface.
Article
Physics, Multidisciplinary
Tae Gwan Park, Jae Ho Jeon, Seung-Hyun Chun, Sunghun Lee, Fabian Rotermund
Summary: This study investigates the interface effects between VSe2 and topological insulator Bi2Se3 using ultrafast time-resolved spectroscopy. The results show that VSe2 as an electrode does not alter the surface state of Bi2Se3 and enables efficient electron transfer and current flow.
COMMUNICATIONS PHYSICS
(2022)
Article
Nanoscience & Nanotechnology
Faizan Ahmad, Rachana Kumar, Sunil Singh Kushvaha, Mahesh Kumar, Pramod Kumar
Summary: This study analyzed the n-GaN/p-Bi2Se3 topological heterojunction using Raman spectroscopy and ultrafast transient absorption spectroscopy, exploring the surface states, energy levels, charge transfer, and carrier relaxation processes. Electrical measurements were also conducted to investigate the influence of interface states on the electrical and optical performance.
NPJ 2D MATERIALS AND APPLICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Christian Nweze, Tomke E. Glier, Mika Rerrer, Sarah Scheitz, Yalan Huang, Robert Zierold, Robert Blick, Wolfgang J. Parak, Nils Huse, Michael Ruebhausen
Summary: In this study, the plasmonic gold nanoparticles injecting hot carriers into the topological insulator interface of Bi2Se3 nanoribbons were investigated using resonant Raman spectroscopy. The impact of individual gold particles with different sizes on the topological surface states and the phonon modes were resolved. The findings suggest the possibility of locally controlling the electronic properties of the topological insulator by metal nanoparticles through hot carrier injection.
Article
Physics, Applied
Shailja Sharma, Shiv Kumar, Amit Kumar, Kenya Shimada, C. S. Yadav
Summary: This study presents the structural, magnetotransport, and angle-resolved photoemission spectroscopy (ARPES) of Ag-doped Bi2Se3 single crystals. The results show that Ag-doping leads to metallic behavior in the resistivity, magnetoresistance satisfying Kohler's rule, and the dominance of electrons as charge carriers. The ARPES spectra confirm the shift of the Dirac point of the topological surface states towards higher binding energy for Ag-doped samples.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Physics, Applied
Gunta Kunakova, Thilo Bauch, Xavier Palermo, Matteo Salvato, Jana Andzane, Donats Erts, Floriana Lombardi
Summary: The study demonstrates that using SrTiO3 substrate in topological insulator nanoribbons enables tunability of Fermi energy and an ambipolar field effect, while maintaining high mobility of Dirac electrons for transportation, providing an ideal platform to take advantage of the properties of topological surface states.
PHYSICAL REVIEW APPLIED
(2021)
Article
Chemistry, Analytical
Yujiu Jiang, Peng Zhu, Jinge Zhao, Shanshan Li, Yetong Wu, Xiaolu Xiong, Xu Zhang, Yuxiang Liu, Jiangyue Bai, Zihang Wang, Shiqi Xu, Minxuan Wang, Tinglu Song, Zhiwei Wang, Weizhi Wang, Junfeng Han
Summary: In this work, a facile and label-free electrochemical biosensor based on intrinsic topological insulator (TI) Bi2Se3 and peptide was designed for the detection of immune checkpoint molecules. The biosensor showed stable and sensitive electron transport due to the robust surface states of Bi2Se3 with low electronic noise. The peptide served as a suitable recognition unit for immune checkpoint molecules, as it could be easily synthesized and chemically modified, and had good biocompatibility and bioavailability. The designed peptide/Bi2Se3 biosensor demonstrated a linear detection range from 3.6 x 10-10 mg mL-1 to 3.6 x 10-5 mg mL-1 and a detection limit of 1.07 x 10-11 mg mL-1. It also exhibited good selectivity and stability.
ANALYTICA CHIMICA ACTA
(2023)
Article
Physics, Applied
Muhammad Nadeem, Chao Zhang, Dimitrie Culcer, Alex R. Hamilton, Michael S. Fuhrer, Xiaolin Wang
Summary: By employing a gate-induced topological quantum phase transition, edge state transport in a topological insulator material can be controlled. This study suggests that zigzag-Xene nanoribbons are promising materials for topological electronics, displaying unique physical characteristics related to intrinsic band topology and finite-size effects on gate-induced topological switching.
APPLIED PHYSICS REVIEWS
(2022)
Article
Physics, Applied
Yanan Liu, Zhongyao Li
Summary: The coupling of topological interface states in Bi2Se3/Bi2Se3 and TlSe/TlSe junctions leads to an energy gap at the Dirac point, which exponentially decays with increasing interface spacing. The law of exponential decay can help identify the formation of interface states and suggests that the coupling is caused by quantum tunneling. Intercalating hexagonal BN can greatly enhance the interfacial coupling, while bilayer BN or single atomic Au layer intercalation can further enhance this coupling effect.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Chemistry, Physical
Dan Wang, Cui-E Hu, Li-Gang Liu, Min Zhang, Xiang-Rong Chen
Summary: In this study, an effective method to introduce magnetism into topological insulators was obtained, and single crystal C-Bi2Se3 was successfully fabricated. The structural, electrical and magnetic properties of doped non-magnetic element X (B, C, and N) in Bi, Se1, Se2, and VDW gap sites of Bi2Se3 were investigated. It was found that C doping in Bi2Se3 resulted in the formation of impurity bands inside the bulk inverted energy gap near the Fermi level. Theoretical calculations and experiments confirmed that carbon-doped Bi2Se3 is ferromagnetic, which provides a plan for manipulating topological properties and exploring spintronic applications.
Article
Quantum Science & Technology
Jonghoon Kim, Kwangsik Jeong, Hanbum Park, Seokbo Hong, Dajung Kim, Gihwan Nam, Seungwon Rho, Hee Jun Shin, Chul Kang, Mann-Ho Cho
Summary: In this work, the suppression of surface properties in Bi2Se3 of various thicknesses grown on antiferromagnetic NiO, which has a strong exchange interaction is investigated. The study found that under perpendicular magnetic fields, a drastic decrease in mobility mu and in the number of phase coherent channels alpha in 5 QL Bi2Se3 on NiO are observed. Additionally, the THz transmission study shows that an increase in the surface penetration depth xi can accelerate the hybridization of surface states, which is also verified using the optical pump THz probe. This rapid collapse of surface states indicates the unique role of antiferromagnetic materials in band overlap, suggesting that the topological surface nature can be modulated by forming an antiferromagnet-topological insulator heterostructure.
ADVANCED QUANTUM TECHNOLOGIES
(2023)
Article
Materials Science, Multidisciplinary
Na Li, Yun-bin Sun, Rui Sun, Xu Yang, Wei Zhang, Zong-kai Xie, Jia-nan Liu, Yan Li, Yang Li, Zi-zhao Gong, Xiang-qun Zhang, Wei He, Zhao-hua Cheng
Summary: Topological insulators with distinct topological surface states have been widely investigated for spintronics and quantum information devices. This study reveals that the topological surface states can significantly accelerate ultrafast demagnetization and enhance the damping factor of heterostructures. These findings have implications for future topological spintronic devices or quantum information processing.
Article
Engineering, Electrical & Electronic
Yogesh Kumar, Prince Sharma, V. P. S. Awana
Summary: In this study, bismuth selenide thin films of varying thicknesses were deposited on a SiO2 substrate. The films were characterized and their transport properties were investigated, revealing the thickness dependence of weak anti-localization effect in Bi2Se3/SiO2 thin films.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2022)
Article
Nanoscience & Nanotechnology
Wen Wang, Haocheng Lei, Ashu Wang
Summary: In this study, the friction behavior of Bi2Se3 was investigated using conductive friction force microscopy under ultra-high vacuum conditions. The experimental results revealed a non-monotonic enhancement of friction, with the emergence of two friction peaks. Further investigations demonstrated that this anomalous friction behavior originated from the formation and rupture of multiple thermally activated sub-contacts.
Article
Chemistry, Multidisciplinary
Haijie Chen, Joao N. B. Rodrigues, Alexander J. E. Rettie, Tze-Bin Song, Daniel G. Chica, Xianli Su, Jin-Ke Bao, Duck Young Chung, Wai-Kwong Kwok, Lucas K. Wagner, Mercouri G. Kanatzidis
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2019)
Article
Physics, Applied
Zhe Cheng, Chiheng Dong, He Huang, Shifa Liu, Yanchang Zhu, Dongliang Wang, Vitalii Vlasko-Vlasov, Ulrich Welp, Wai-Kwong Kwok, Yanwei Ma
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2019)
Article
Multidisciplinary Sciences
Jing Xu, Meng K. Ma, Maksim Sultanov, Zhi-Li Xiao, Yong-Lei Wang, Dafei Jin, Yang-Yang Lyu, Wei Zhang, Loren N. Pfeiffer, Ken W. West, Kirk W. Baldwin, Mansour Shayegan, Wai-Kwong Kwok
NATURE COMMUNICATIONS
(2019)
Article
Chemistry, Multidisciplinary
Haijie Chen, Jiangang He, Christos D. Malliakas, Constantinos C. Stoumpos, Alexander J. E. Rettie, Jin-Ke Bao, Duck Young Chung, Wai-Kwong Kwok, Christopher Wolverton, Mercouri G. Kanatzidis
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2019)
Article
Multidisciplinary Sciences
Ivan A. Sadovskyy, Alexei E. Koshelev, Wai-Kwong Kwok, Ulrich Welp, Andreas Glatz
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2019)
Article
Multidisciplinary Sciences
Maxime Leroux, Vivek Mishra, Jacob P. C. Ruff, Helmut Claus, Matthew P. Smylie, Christine Opagiste, Pierre Rodiere, Asghar Kayani, G. D. Gu, John M. Tranquada, Wai-Kwong Kwok, Zahirul Islam, Ulrich Welp
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2019)
Article
Physics, Applied
Andreas Glatz, Ivan A. Sadovskyy, Ulrich Welp, Wai-Kwong Kwok, George W. Crabtree
JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM
(2020)
Article
Chemistry, Multidisciplinary
Haijie Chen, Rebecca McClain, Jiangang He, Chi Zhang, Jack N. Olding, Roberto dos Reis, Jin-Ke Bao, Ido Hadar, Ioannis Spanopoulos, Christos D. Malliakas, Yihui He, Duck Young Chung, Wai-Kwong Kwok, Emily A. Weiss, Vinayak P. Dravid, Christopher Wolverton, Mercouri G. Kanatzidis
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2019)
Article
Physics, Applied
Zhongtang Xu, Chiheng Dong, Fan Fan, Vitalii Vlasko-Vlasov, Ulrich Welp, Wai-Kwong Kwok, Yanwei Ma
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2020)
Article
Physics, Applied
G. Kuwano, M. Tsujimoto, Y. Kaneko, T. Imai, Y. Ono, S. Nakagawa, S. Kusunose, H. Minami, T. Kashiwagi, K. Kadowaki, Y. Simsek, U. Welp, W-K. Kwok
PHYSICAL REVIEW APPLIED
(2020)
Article
Physics, Multidisciplinary
D. Collomb, S. J. Bending, A. E. Koshelev, M. P. Smylie, L. Farrar, J-K Bao, D. Y. Chung, M. G. Kanatzidis, W-K Kwok, U. Welp
Summary: Quantitative magnetic imaging of superconducting vortices in RbEuFe4As4 showed a pronounced suppression of superfluid density near the magnetic ordering temperature, indicating a significant exchange interaction between the superconducting and magnetic subsystems. This has important implications for future investigations of physical phenomena arising from the interplay between them.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Ramakanta Chapai, Maxime Leroux, Vincent Oliviero, David Vignolles, Nicolas Bruyant, M. P. Smylie, D. Y. Chung, M. G. Kanatzidis, W. -k. Kwok, J. F. Mitchell, Ulrich Welp
Summary: The layered kagome metals of composition AV3Sb5 (A = K, Rb, Cs) recently discovered exhibit a complex interplay among various electronic states. In this study, quantum oscillation measurements in pulsed fields up to 86 T were used to probe the electronic band structure of CsV3Sb5. The high-field data reveal a folded Fermi surface and the existence of large triangular Fermi surface sheets.
PHYSICAL REVIEW LETTERS
(2023)
Article
Materials Science, Multidisciplinary
M. P. Smylie, Kaya Kobayashi, T. Takahashi, C. Chaparro, A. Snezhko, W-K Kwok, U. Welp
Article
Materials Science, Multidisciplinary
V. K. Vlasko-Vlasov, U. Welp, A. E. Koshelev, M. Smylie, J-K Bao, D. Y. Chung, M. G. Kanatzidis, W-K Kwok
Article
Materials Science, Multidisciplinary
K. Willa, M. P. Smylie, Y. Simsek, J. -K. Bao, D. Y. Chung, M. G. Kanatzidis, W. -K. Kwok, U. Welp