Condensed Matter Physics
Spin-Echo Technique Reveals 1/f Charge Noise as Dominant Dephasing Mechanism in Charge-Based Cooper-Pair Box
Researchers apply a spin-echo-type pulse sequence using gate-voltage pulses to a charge-based two-level system in a Cooper-pair box, enabling refocused echo signals that mitigate inhomogeneity in ensemble measurements. The observed echo decay time aligns with estimated decoherence times, indicating …
Multi-Directional FIB Etching Enables Nanoscale High-Quality Nb Josephson Junctions for SETs
Researchers developed a focused-ion-beam (FIB) etching process from multiple directions to fabricate nanoscale Nb/(Al-)Al2O3/Nb tunnel junctions. Applied to a single-electron transistor (SET), the device exhibited superconducting gap energy and transition temperature matching bulk Nb values, confirm…
Magnon Topology Enhances Quantum Anomalous Hall State Stability
This paper investigates magnon excitations in moiré Chern ferromagnets, focusing on their influence on magnetic stability and transition temperature at integer filling factor \nu = -1. The research reveals that magnon spectra exhibit isolated low-energy bands whose topological character is tunable v…
High Magnetic Fields Induce Novel Phases in 3D Electron Gases
This paper investigates the behavior of three-dimensional electron gases under strong magnetic fields, exploring how interactions and symmetry breaking can lead to various emergent phases. The focus is on the competition between charge density waves and superconductivity under different perturbation…
Direct Measurement of Long-Range Phase Coherence in Hybrid Josephson Junction Arrays
This research directly images local susceptibility in hybrid Josephson junction arrays using scanning SQUID, providing insights into superconductivity coherence and its suppression near quantum phase transitions. The study reveals the amplitude and spatial phase structures of superconducting states …
Andreev Diffraction in Superconductor-Semiconductor Hybrids Enables Phase Control
This research demonstrates the realization of Andreev diffraction gratings in superconductor-semiconductor hybrid circuits. By precisely controlling the phase differences between multiple Andreev scatterers, the study achieves tunable diffraction patterns. This methodology enables individual phase c…
Optical Evidence of Interlayer Electron Coherence via Exciton Hybridization in Doped MoS2 Bilayers
In electron-doped MoS2 homobilayers, indirect excitons with opposing dipoles hybridize unusually under negligible tunneling conditions, exhibiting behavior distinct from level crossing or anti-crossing. This is attributed to static random coupling that strengthens with electron density and weakens w…
Electrical Fields Enable Dynamic Tuning of Exciton Emission and Decay in TMD Heterostructures
Researchers achieve dynamical control of long-lived interlayer excitons in angle-aligned MoSe2/WSe2 heterostructures using fast electrical gating. Out-of-plane dipole moments allow electric fields to tune emission wavelength mid-lifetime, while patterned gates enable rapid local doping to toggle rad…
Quantum Crystal-to-Liquid Transition in MoSe2 Monolayer Yields Electronic Microemulsion Phase
Researchers observe a microemulsion phase between Wigner crystal and electron liquid in a MoSe2 monolayer using cryogenic reflectance and magneto-optical spectroscopy. The transition shows anomalies in exciton reflectance, spin susceptibility, and Umklapp scattering, confirming a distinct mixed stat…
Electrostatic Trap Enables High-Density Interlayer Excitons with Tunable Ionization Threshold in 2D Heterostructures
Researchers use electrostatic gates in atomically thin heterostructures to trap interlayer excitons (IEs) and achieve densities exceeding 2×10¹² cm⁻² via Stark shift modulation. At high densities, linewidth broadening indicates an IE ionization transition that is independent of trap depth. This thre…
Local Noise Spectroscopy Enables High-Resolution Imaging and Phonon Analysis of 2D Wigner Crystals
Local electromagnetic noise spectroscopy is proposed as a noninvasive method to probe Wigner crystal phases in strongly interacting 2D electron systems. At probe-sample distances below inter-electron spacing, it achieves single-site resolution for in-plane electron crystal imaging. At larger distanc…
Gradual Insulating Crossover in 2D Josephson-Junction Arrays Revealed by Nonlinear BKT Transport
Experiments on 2D JJAs show no sharp superconductor-insulator transition but a gradual crossover to the insulating phase as EJ/EC decreases, evidenced by temperature-dependent resistance. Low-T I-V curves follow I = cV + bV^a, modeled via BKT with finite-range logarithmic Cooper-pair interactions, e…
Magnon-Exciton Coupling Achieved via YIG-MoSe2 van der Waals Heterointerface
Researchers demonstrate magnon-exciton proximity coupling at the interface between a YIG thin film hosting long-lived magnons and a MoSe2 flake with strongly-bound excitons. Magnons induce a dynamical valley Zeeman effect on excitons through interfacial exchange interactions. This hybrid system enab…
Heterodyne Imaging Reveals Band Structures of Damon-Eshbach Modes in 1D Magnonic Crystals
Researchers demonstrate real-space imaging of optical heterodyne signals from Brillouin light scattering by coherently driven magnons in magnetostatic modes. This technique characterizes surface Damon-Eshbach modes in a 1D magnonic crystal formed by aluminum strips on a ferromagnetic film, with band…
Translational Deformations of Periodic Potentials Generate Topological Boundary Modes
Continuous translational deformations of periodic potentials produce localized boundary states, distinct from defect perturbations or terminations. A rigorous theoretical proof establishes their emergence, with experimental validation in microwave photonic crystals. The mechanism manifests topologic…
Gebhard-Ruckenstein Hopping Enables Chiral Microwave Propagation in Superconducting Circulators
Gebhard-Ruckenstein hopping between microwave resonators in a superconducting device produces linear energy dispersion, enabling chiral microwave propagation. This mechanism supports nonreciprocal microwave transmission, allowing the device to function as an on-chip circulator. Attaching transmissio…