介观与纳米尺度物理
We present a theoretical study of spin-wave scattering by a twisted domain wall (DW) in a two-dimensional ferromagnet with easy-axis anisotropy. While the twisted DW generates an effective gauge field for spin waves, leading to a deflection…
We systematically investigate the electronic structures of pristine monolayer WSe$_2$ and WSe$_2$ superlattices with periodic nitrogen substitution. Unlike random doping, which often introduces in-gap impurity states, periodic nitrogen…
Altermagnets possess two key features: non-relativistic alternating spin splitting (i.e., altermagnetism) and a material-dependent N\'{e}el vector. The former naturally coexists with Rashba spin-orbit coupling (SOC) in real materials on…
We review two magnetic tunnel junction (MTJ) approaches for compact, low-power, CMOS-integrated true random number generation (TRNG). The first employs passive-read, easy-plane superparamagnetic MTJs (sMTJs) that generate…
We demonstrate that thermally stable perpendicular magnetic tunnel junctions (pMTJs), widely used in spin-transfer torque magnetic random-access memory, can be actuated with nanosecond pulses to exhibit tunable stochastic behavior. This…
Scaling field-effect transistors (FETs) into the sub-10-nm regime fundamentally alters the transport mechanism, challenging long-standing design rules. This study investigates monolayer TMD FETs with channel lengths from 12 nm to 3 nm,…
Controlling magnetic order on ultrafast timescales, driven by spintronic and recording applications, is one of the main directions of current research in magnetism. Despite major advances in understanding the temporal evolution of magnetic…
We report on all-optical generation and detection of high-frequency (up to about 30 GHz) surface acoustic waves (SAWs) in GaAs/AlGaAs heterostructures with short-period Au gratings on top. A highly sensitive method for SAW detection is…
We study the dynamics of quantum matter interacting with time-energy entangled photons. We consider the stimulation of a collective mode of a two-dimensional material by means of one of the two partners of a time-energy entangled pair of…
We consider the effects of interactions on the edges of ``double" quantum spin Hall insulators (DQSHIs), motivated by recent experiments on moir\'e twisted metal dichalcogenides. Without interactions, a DQSHI can be understood as two copies…
Long ago, life discovered how to efficiently push electrons thermodynamically uphill to lower potential by harnessing energy released by an equal number of electrons moving downhill. Known as electron bifurcation, this form of energy…
Optical spectroscopy based on second-order nonlinearity is a critical technique for characterizing two-dimensional (2D) crystals as well as bioimaging and quantum optics. It is generally believed that second-harmonic generation (SHG) in…
Magnetic phases are commonly identified through macroscopic magnetization, yet many ordered states, including antiferromagnets and altermagnets, possess a vanishing net moment despite distinct local spin structure. We show that such an…
Spin transfer torques (STTs) control magnetisation by electric currents, enabling a range of nano-scale spintronic applications. They can destabilise the equilibrium magnetisation state by counteracting magnetic relaxation. Here, we…
Double-helix (DH) nanowires provide a platform to study the influence of geometric chirality on spin chirality. Their three-dimensional (3D) helical architecture and tunable inter-strand coupling enable control of spin chirality, including…
The anomalous Hall effect has been understood in terms of the geometric nature of Bloch bands and impurity scattering, and has been observed in a wide variety of magnetic materials such as ferromagnets and antiferromagnets. Recently, a…
Discrete charge fluctuations, routinely observed in semiconductor quantum dot devices, may contribute significantly to device drift and errors resulting from qubit miscalibration. Understanding the nature and origins of these discrete…
On-chip THz spectroscopy enables quantitative measurements of the optical conductivity of sub-wavelength 2D materials by tightly confining THz fields in metallic transmission line structures interfaced to the material. However, because the…
Under certain conditions, applying a sequence of voltage pulses of alternating polarities across a resistive switching memory device induces a finite number of fixed-point attractors in its time-averaged dynamics, known as dynamical…
Interfacial thermal transport is a critical bottleneck in nanoscale systems, where heat dissipation and energy efficiency are strongly modulated by molecular ordering at solid-liquid boundaries. Here, using atomistic simulations of…