Search for: All records

Orbital current has attracted significant attention in recent years due to its potential for energy-efficient magnetization control without the need for materials with strong spin–orbit coupling. However, the fundamental mechanisms governing orbital transport remain elusive. In this study, we systematically explore orbital transport in Ti/Ni bilayers through orbital pumping, drawing an analogy to spin pumping. The orbital current is generated and injected into the Ti layer via the microwave-driven orbital dynamics in Ni, facilitated by its strong spin–orbit correlation. We employed thickness-dependent ferromagnetic resonance measurements and angular-dependent inverse orbital Hall effect (IOHE) detection to probe orbital transport in Ti based on the conventional spin-pumping methodology. The observed enhancement in the damping factor indicates an orbital-diffusion length of ∼5.3 ± 3.7 nm, while IOHE-based estimation suggests a value of around 4.0 ± 1.2 nm, which confirms its short orbital-diffusion length. Furthermore, oblique Hanle measurements in the longitudinal configuration reveal an orbital relaxation time of approximately 16 ps. Our results establish that orbital pumping, analogous to the conventional spin-pumping framework, can serve as a robust technique for elucidating orbital transport mechanisms, paving the way for the design of efficient spin-orbitronic devices. 

Rashba spin–orbit coupling locks the spin with the momentum of charge carriers at the broken inversion interfaces, which could generate a large spin galvanic response. Here, we demonstrate spin-to-charge conversion (inverse Rashba–Edelstein effect) in KTaO3(111) two-dimensional electron systems. We explain the results in the context of electronic structure, orbital character, and spin texture at the KTaO3(111) interfaces. We also show that the angle dependence of the spin-to-charge conversion on in-plane magnetic field exhibits a nontrivial behavior, which matches the symmetry of the Fermi states. Results point to opportunities to use spin-to-charge conversion as a tool to investigate the electronic structure and spin texture. 

Amino acid identification is crucial across various scientific disciplines, including biochemistry, pharmaceutical research, and medical diagnostics. However, traditional methods such as mass spectrometry require extensive sample preparation and are time-consuming, complex and costly. Therefore, this study presents a pioneering Machine Learning (ML) approach for automatic amino acid identification by utilizing the unique absorption profiles from an Elliptical Dichroism (ED) spectrometer. Advanced data preprocessing techniques and ML algorithms to learn patterns from the absorption profiles that distinguish different amino acids were investigated to prove the feasibility of this approach. The results show that ML can potentially revolutionize the amino acid analysis and detection paradigm. 

Improving the photon-magnon coupling strength can be done by tuning the structure of microwave resonators to better interact with the magnon counterpart. Planar resonators accommodating unconventional photon modes beyond the half- and quarter-wavelength designs have been explored due to their optimized mode profiles and potentials for on-chip integration. Here, we designed and fabricated an actively controlled ring resonator supporting the spoof localized surface plasmons (LSPs), and implemented it in the investigation of photon-magnon coupling for hybrid magnonic applications. We demonstrated gain-assisted photon-magnon coupling with the YIG magnon mode under several different sample geometries. The achieved coupling amplification largely benefits from the high quality factor (Q-factor) due to the additional gain provided by a semiconductor amplifier, which effectively increases the Q-factor from a nearly null state (passive resonance) to more than 1000 for a quadrupole LSP mode. Our results suggest an additional control knob for manipulating photon-magnon coupled systems exploiting external controls of gain and loss. 

This research introduces a novel method for evaluating the structural features of biomolecules, utilizing our innovative Elliptical Dichroism (ED) spectrometer specifically designed for stereochemical analysis. By integrating ED spectrometry with autocorrelation (AC) analysis, we investigate the conformational characteristics of biological molecules such as amino acids, proteins, and extracellular vesicles (EVs) induced by elliptically polarized UV absorption. Our streamlined approach offers a cost-effective and portable solution with minimal sample consumption and supports multiple working modes to efficiently characterize biomolecular structures. The insight from this new approach demonstrates potential applications in using biomolecular characterization for cancer detection. 

By employing coarse-grained (CG) molecular dynamics (MD) simulations, this study aims to investigate the thermomechanical behaviors of graphene-reinforced conjugated polymer nanocomposites at a fundamental molecular level.