Article
Physics, Multidisciplinary
Young Woo Choi, Marvin L. Cohen
Summary: We investigated the electromigration forces for weakly bonded adsorbates on graphene using density-functional based calculations. The results showed that the nature of electromigration forces depends critically on the energy level alignment between the adsorbate state and the Fermi level of the graphene. For resonant adsorbates, the electromigration force is dominated by the electron wind force, while for nonresonant adsorbates, it is essentially the direct force dependent on the adsorbate charge. Moreover, we demonstrated that the magnitude of electromigration forces can be continuously adjusted through electrostatic gating for resonant adsorbates.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Emmanuel Picheau, Anthony Impellizzeri, Dmitry Rybkovskiy, Maxime Bayle, Jean-Yves Mevellec, Ferdinand Hof, Hassan Saadaoui, Laure Noe, Abraao Cefas Torres Dias, Jean-Luc Duvail, Marc Monthioux, Bernard Humbert, Pascal Puech, Christopher P. Ewels, Alain Penicaue
Summary: Above a critical diameter, carbon nanotubes collapse into flattened forms, leading to unique Raman spectra changes. The presence of edge cavities and curvature changes near the edges activate a D band despite overall continuity in the structure. The differing perspectives of chemists and physicists on defects in carbon structures may lead to confusion for researchers in nanotechnologies.
Article
Biochemical Research Methods
Olena S. Oliinyk, Chenshuo Ma, Sergei Pletnev, Mikhail Baloban, Carlos Taboada, Huaxin Sheng, Junjie Yao, Vladislav V. Verkhusha
Summary: Using rational design, we developed a 17 kDa cyanobacteriochrome-based near-infrared (NIR-I) fluorescent protein, miRFP718nano, which efficiently binds endogenous biliverdin chromophore and emits bright fluorescence in mammalian cells and tissues. With a maximal emission at 718 nm and an emission tail in the short-wave infrared (SWIR) region, miRFP718nano enables deep-penetrating off-peak fluorescence imaging in vivo. We demonstrated the superiority of miRFP718nano-enabled SWIR imaging in various applications, including imaging of microbes in the mouse digestive tract, mammalian cells injected into the mouse mammary gland, and NF-kB activity in a mouse model of liver inflammation.
Article
Nanoscience & Nanotechnology
Kevin Laughlin, Richard R. Vanfleet, Robert C. Davis
Summary: Researchers have developed VACNT/carbon composite films with higher stiffness and strength than pure VACNTs, while maintaining low reflectance. These composites can withstand water exposure and handling, making them a promising material.
ACS APPLIED NANO MATERIALS
(2022)
Article
Multidisciplinary Sciences
Pichawee Aieamsam-Aung, Atthapon Srifa, Wanida Koo-Amornpattana, Suttichai Assabumrungrat, Prasert Reubroycharoen, Phorndranrat Suchamalawong, Choji Fukuhara, Sakhon Ratchahat
Summary: The hydrogenation of CO2 enables the efficient utilization of renewable biogas by upgrading methane. This process has potential benefits for storage of renewable hydrogen energy and reduction of greenhouse gas emissions. A prototype reactor with double pass operation was used, along with an optimized Ni-Ce/Al-MCM-41 catalyst, to investigate the upgradation process. The results showed that the double pass operation significantly increased CO2 conversion and methane production yield, resulting in a higher purity of biomethane.
SCIENTIFIC REPORTS
(2023)
Article
Multidisciplinary Sciences
Daniel Popa, Richard Hopper, Syed Zeeshan Ali, Matthew Thomas Cole, Ye Fan, Vlad-Petru Veigang-Radulescu, Rohit Chikkaraddy, Jayakrupakar Nallala, Yuxin Xing, Jack Alexander-Webber, Stephan Hofmann, Andrea De Luca, Julian William Gardner, Florin Udrea
Summary: The gas sensor market is rapidly growing due to various socioeconomic and industrial factors, with a particular demand for high-performance MIR gas sensors in healthcare, smart homes, and the automotive sector. Researchers have developed an on-chip broadband thermal MIR source based on CMOS technology and a CNT blackbody layer, offering an ideal solution for low-cost, highly-integrated MIR spectroscopy.
SCIENTIFIC REPORTS
(2021)
Article
Chemistry, Physical
Qian Shao, Ruishan Li, Zuogong Yue, Yanlei Wang, Enlai Gao
Summary: This study discovered two new ultrahigh-modulus crystals through data mining and first-principles verifications, providing new insights and methods for the discovery and research of high-modulus materials. The mechanical behaviors of the ultrahigh-modulus crystals were explored through testing and analysis, while data-driven analysis identified crucial structural features correlated to the maximum Young's moduli of crystals.
CHEMISTRY OF MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Duan-Chao Wang, Hou-Yong Yu, Zhaofeng Ouyang, Dongming Qi, Ying Zhou, Anqi Ju, Ziheng Li, Yiwen Cao
Summary: In this study, composite fibers with chain-ring structures were prepared by connecting cellulose nanofiber (CNF) and multi-walled carbon nanotubes (MWCNT) covalently, solving the problems of MWCNT aerogel formation and phase separation during compounding. The resulting aerogels exhibited mechanical resilience and chain-ring fibers, enabling high compression resistance and application in flexible supercapacitors and sensors.
Article
Chemistry, Multidisciplinary
Ankur Chattopadhyay, Srinivas Rao Sampathirao, Omkar Hegde, Saptarshi Basu
Summary: This article presents an approach to generating contrasting patterns from drying colloidal droplets in a liquid bridge configuration. The confinement distance plays a crucial role in the formation of different deposition patterns. Alteration of the confinement distance leads to variations in flow inside the liquid bridges, resulting in different deposition patterns. Small confinement distance results in stick-slip motion, while large confinement distance exhibits pinned contact lines.
Article
Chemistry, Physical
Yu Li, Jin-Wu Jiang
Summary: This study investigates the mechanisms of structural transitions in carbon peapods and the effects of vacancy defects, using machine-learned potentials. The developed potentials accurately reproduce experimental carbon structures and provide insights into the development of novel carbon allotropes.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Physics, Applied
Victor I. Kleshch, Vitali Porshyn, Pavel Serbun, Anton S. Orekhov, Rinat R. Ismagilov, Dirk Luetzenkirchen-Hecht, Alexander N. Obraztsov
Summary: Surface graphitization of needlelike diamond nanotips can be achieved by Joule heating, resulting in well-ordered graphene layers and better emission currents, making them promising for various applications.
APPLIED PHYSICS LETTERS
(2022)
Review
Energy & Fuels
Jin-Myung Choi, Jiye Han, Tushar Rane, Soyeon Kim, Ick Soo Kim, Il Jeon
Summary: This review discusses the fundamentals of utilizing SWCNTs in PSCs, including their characteristics as electron-transporting layer, hole-transporting layer, photoactive layer, and interfacial materials. It also presents strategies to improve PSCs performance through defect control and enhancement of electrical and morphological properties.
JOURNAL OF PHYSICS-ENERGY
(2022)
Article
Chemistry, Inorganic & Nuclear
Yi Yang, Iker Del Rosal, Michael J. Ferguson, Robert McDonald, Laurent Maron, Josef Takats
Summary: This study reports the synthesis, characterization, and solid-state structure of bulky alkoxy- and aryloxy-supported yttrium polynuclear hydrides. Hydrogenolysis of the alkoxy-anchored yttrium dialkyl resulted in the clean conversion to tetranuclear dihydride, while hydrogenolysis of the aryloxy yttrium dialkyl gave a mixture of tetranuclear and trinuclear polyhydrides. The isolation of each component was achieved through optimization.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Shiwei Zhao, Qinfeng Liu, Anqian Yuan, Zhimeng Liu, Shiyi Zhou, Xiaowei Fu, Jingxin Lei, Liang Jiang
Summary: In this study, a uniquely intrinsic toughened thermosetting epoxy resin (EPU) was synthesized by integrating a polyurethane system into traditional epoxy resins. The EPU showed tunable and remarkable mechanical properties and exhibited thermal- and electric-induced shape plasticity.
MATERIALS CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Multidisciplinary
Vaskuri C. S. Theja, Vaithinathan Karthikeyan, Dani S. Assi, Saianand Gopalan, Vellaisamy A. L. Roy
Summary: This article investigates the effect of multiwalled carbon nanotube (MWCNT) inclusions on the thermoelectric performance of Cu3SbS4. The results demonstrate that adding an optimal amount of MWCNT inclusions significantly improves the Seebeck coefficient and reduces the thermal conductivity of Cu3SbS4. The optimized composite sample achieves a maximum figure of merit (ZT) of 0.43 at 623 K, which is 70% higher than pristine Cu3SbS4. In addition, the addition of nanoinclusions also enhances the mechanical stability of the samples.
Article
Chemistry, Multidisciplinary
Lucia Vigliotti, Alessio Calzona, Niccolo Traverso Ziani, F. Sebastian Bergeret, Maura Sassetti, Bjoern Trauzettel
Summary: Josephson junctions in the presence of a magnetic field can exhibit different interference patterns based on the spatial distribution of the supercurrent. In this study, a topological Josephson junction is investigated with extended edge states. It is found that the interference pattern, driven by dominant crossed Andreev reflections and overlapped edge states, approaches a periodicity of 2 phi(0).
Article
Physics, Multidisciplinary
Daniel Miller, Daniel Loss, Ivano Tavernelli, Hermann Kampermann, Dagmar Bruss, Nikolai Wyderka
Summary: The Shor-Laflamme distribution is a set of local unitary invariants that measure k-body correlations in a quantum state. We demonstrate that the distribution of graph states can be obtained by solving a graph-theoretical problem, allowing for the calculation of mean and variance using graph properties. We also derive closed expressions for the distribution of certain graph state families. Our results provide insights into quantum error-correcting codes and the geometry of quantum states. We propose an entanglement criterion based on the Shor-Laflamme distribution, which can be applied to higher-dimensional systems.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2023)
Article
Physics, Multidisciplinary
J. Yoneda, J. S. Rojas-Arias, P. Stano, K. Takeda, A. Noiri, T. Nakajima, D. Loss, S. Tarucha
Summary: Research shows strong noise correlation between neighboring silicon spin qubits, with electric field fluctuations creating strongly correlated errors.
Article
Physics, Multidisciplinary
Aritra Lahiri, Sang -Jun Choi, Bjoern Trauzettel
Summary: Josephson tunnel junctions exhibit a supercurrent proportional to the sine of the superconducting phase difference. Voltage pulses with sharp temporal variations significantly influence the term proportional to the cosine of the phase difference. The nonequilibrium fractional Josephson effect arises from the interference of nonequilibrium virtual quasiparticle excitations, and it is independent of the ground state fermion parity in topological Josephson junctions.
PHYSICAL REVIEW LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Katharina Laubscher, Dmitry Miserev, Vardan Kaladzhyan, Daniel Loss, Jelena Klinovaja
Summary: We study the spin configurations of magnetic impurities near the edge of a two-dimensional topological superconductor through both analytical and numerical methods. We find that the spin of a single impurity tends to align along the edge due to the interaction between the impurity and the gapless Majorana edge states. Additionally, when two impurities are placed close to the edge, the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction between them is mainly mediated by the Majorana edge states, resulting in a ferromagnetic alignment of the spins along the edge. This effect can be utilized for detecting the helical Majorana edge states.
Article
Materials Science, Multidisciplinary
Alexander Mook, Rhea Hoyer, Jelena Klinovaja, Daniel Loss
Summary: We study quantum condensed matter systems where particle number is not conserved, leading to topological anticrossings in the spectrum due to hybridization of states from different particle-number sectors. This phenomenon is observed in fully saturated spin-anisotropic quantum magnets, where single magnons hybridize with magnon bound pairs. The resulting chiral edge excitations are composite particles with mixed spin-multipolar character, showing genuine quantum mechanical effects that vanish in the classical limit. These findings have implications for intrinsic anomalous Hall-type transport, suggesting that fully polarized quantum magnets can serve as a promising platform for studying topological effects caused by hybridizations between particle-number sectors.
Article
Materials Science, Multidisciplinary
Melina Luethi, Katharina Laubscher, Stefano Bosco, Daniel Loss, Jelena Klinovaja
Summary: Planar Josephson junctions made of semiconductors with strong spin-orbit interaction (SOI) offer a promising platform for hosting Majorana bound states (MBSs). Previous studies focused on electron gases with linear momentum-dependent SOI, whereas a two-dimensional hole gas in planar germanium (Ge) exhibits cubic momentum-dependent SOI. However, we demonstrate that due to its particularly large SOI, Ge is a favorable material for MBS emergence. Using a discretized model, we numerically simulate a Ge planar Josephson junction and find that even cubic SOI can lead to the formation of MBSs. Interestingly, we observe an asymmetric phase diagram in the presence of cubic SOI. Furthermore, trivial Andreev bound states can mimic the signatures of MBSs in a Ge planar Josephson junction, posing challenges for experimental detection.
Article
Materials Science, Multidisciplinary
Silas Hoffman, Daniel Loss, Yaroslav Tserkovnyak
Summary: Spin superfluidity in low-dimensional systems with small spins suffers from strong quantum fluctuations, affecting its topological protection. By studying spin transport through a finite spin-1/2 magnetic chain, we investigate the inheritance of spin superfluidity from classical magnets. We show that the topological properties of semiclassical spin superfluids are related to topological superconductivity in the fermionic representation. In particular, we observe efficient spin transmission through the magnetic region at a characteristic resonant length, which is influenced by the boundary Majorana zero modes.
Article
Materials Science, Multidisciplinary
Melina Luethi, Henry F. Legg, Katharina Laubscher, Daniel Loss, Jelena Klinovaja
Summary: In this study, we investigate superconductor-normal-superconductor-normal-superconductor (SNSNS) planar Josephson junctions in hole systems. By manipulating the superconducting phase difference, we demonstrate the possibility of achieving a topological superconducting phase with Majorana bound states, which overcomes previous experimental challenges.
Article
Physics, Applied
J. S. Rojas-Arias, A. Noiri, P. Stano, T. Nakajima, J. Yoneda, K. Takeda, T. Kobayashi, A. Sammak, G. Scappucci, D. Loss, S. Tarucha
Summary: In this study, we detected correlations in qubit-energy fluctuations of non-neighboring qubits in isotopically purified Si/Si-Ge quantum dots. The correlation coefficient reached 10% for a next-nearest-neighbor qubit-pair separated by 200 nm at low frequencies where the noise is strongest. We also found correlations with the charge-sensor signal reaching up to 70%, proving the electrical origin of the observed noise. A simple theoretical model accurately reproduced the measurements and predicted a polynomial decay of correlations with interqubit distance. These results quantify the long-range correlations of noise in quantum-dot spin-qubit arrays, which are essential for scalability and fault tolerance.
PHYSICAL REVIEW APPLIED
(2023)
Review
Physics, Applied
Peter Stano, Daniel Loss
Summary: This Technical Review collects and curates experimentally achieved values of selected performance characteristics of semiconductor spin qubits in electrically controlled nanostructures. It aims to provide a community source for comparing different spin-qubit platforms using agreed definitions of figures of merit. The focus is on the values of these characteristics reported in the literature, rather than their motivation or significance. The Review surveys the progress of semiconducting spin qubits over the past two decades in terms of coherence, speed, fidelity, and multi-qubit array size.
NATURE REVIEWS PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Aleksandr E. Svetogorov, Daniel Loss, Jelena Klinovaja
Summary: In this theoretical study, we investigate a Josephson junction between superconductors in the presence of quasiparticle poisoning. We find that the voltage signals from the junction in both the trivial and topological phases are distinctive enough to distinguish between trivial Andreev and topological Majorana bound states. Furthermore, these voltage signatures can be used to directly measure the quasiparticle poisoning rates in both phases.
Article
Materials Science, Multidisciplinary
Henry F. Legg, Daniel Loss, Jelena Klinovaja
Summary: This study investigates the effects of coupling between a superconducting layer and a topological insulator nanowire. The research shows that metallization of states in the nanowire caused by the superconductor leads to a shift of energy sub-bands and a reduction in the sub-band gap size. However, metallization effects in the nanowires can also enhance the sub-band splitting, which is crucial for achieving topological superconductivity. Unlike in semiconductors, the metallization effects in topological insulator nanowires can be relatively easily mitigated.
Article
Materials Science, Multidisciplinary
Flavio Ronetti, Daniel Loss, Jelena Klinovaja
Summary: We theoretically investigate the spiral-staircase Heisenberg spin-1/2 ladder with antiferromagnetic long-range spin interactions and a uniform magnetic field. We show that the system exhibits a partially gapped magnetic phase with fractional spin excitations when the magnetizations of the two chains forming the ladder satisfy certain resonance conditions. These fractional spin excitations can be probed and measured through magnetization and spin currents, and in some cases, the spin conductance reaches universal values.
Article
Materials Science, Multidisciplinary
Christoph Adelsberger, Monica Benito, Stefano Bosco, Jelena Klinovaja, Daniel Loss
Summary: Hole-spin qubits in quasi-one-dimensional structures in Ge semiconductors are investigated for their potential in quantum information processing. The study focuses on optimizing the strong spin-orbit interaction (SOI) and explores the effects of electric and magnetic fields on one-dimensional hole systems. The results show that orbital effects significantly renormalize the g factor and there exists a sweet spot in the nanowire structure where charge noise is strongly suppressed, leading to highly coherent qubits with large Rabi frequencies.
