⭕ Unconventional quantum Hall effect in high-mobility Q-valley electrons 

This work reports quantum transport studies of Q-valley electrons in few-layer transition metal disulfides (TMDs), enabled by high-mobility BN-encapsulated devices with optimized contacts. Pronounced Shubnikov–de Haas oscillations and the onset of quantum Hall plateaus are observed, revealing distinct Zeeman responses: a valley Zeeman effect in odd-layer TMDs and a spin Zeeman effect in even-layer TMDs. These contrasting behaviors arise from the presence or absence of inversion symmetry, which dictates spin–valley coupling at the Q valleys. The results extend the unique spin–valley physics of monolayer TMDs to few-layer systems, providing new insights into multi-valley band structures and unconventional quantum Hall effects. 

Even–odd layer-dependent magnetotransport of high-mobility Q-valley electrons in transition metal disulfides,

Nature Communications 7, 12955 (2016).

⭕ Electric-field control of the Berry curvature dipole

This work reports the intrinsic nonlinear Hall effect in twisted bilayer graphene (TBG), arising from a Berry curvature dipole within its flatbands. Unlike extrinsic effects caused by disorder scattering in graphene superlattices, the observed second harmonic Hall voltage here directly reflects the intrinsic Berry curvature distribution. Applying a displacement field shifts the Berry curvature hotspots, enabling tunable direction and amplitude of the nonlinear Hall response. These results demonstrate that high-quality TBG serves as a sensitive platform for probing Berry curvature and for potential applications in second harmonic generation and rectification. 

Intrinsic nonlinear Hall effect and gate-switchable Berry curvature sliding in twisted bilayer graphene,

Physical Review Letters 131, 066301 (2023) editors' suggestion.

⭕ Detection of correlated quantum phase transitions through topological nonlinear transport measurements

The recently discovered nonlinear Hall effect (NHE) in a few non-interacting topological systems provides a novel mechanism for generating second-harmonic electrical Hall signals under time-reversal-symmetric conditions. In this study, we demonstrate a giant nonlinear Hall effect in twisted WSe2 bilayers, enabled by moiré flat bands and strong electron correlations. At half-filling of the first moiré band, the NHE signal peaks sharply, showing a generation efficiency over two orders of magnitude higher than previously reported materials. The enhancement is closely tied to correlation-driven phenomena, with resistivity data suggesting a mass-diverging continuous Mott transition near the insulating state. These findings highlight how moiré engineering can combine Berry curvature dipoles with interaction effects to generate novel quantum responses and establish NHE as a powerful probe of quantum criticality.

Giant nonlinear Hall effect in twisted bilayer WSe₂,

National Science Review 10, nwac232 (2023). ESI highly cited paper. NSR 2025 "Best Paper Award"

⭕ In-situly oxided graphene membrane for high effecient proton transport

This study demonstrates that monolayer graphene oxide (GO) membranes are simultaneously impermeable to gases and highly conductive to protons across the basal plane. Contrary to the common assumption of abundant nanoscale pinholes, micrometer-scale GO areas show no helium leakage while exhibiting proton conductivity nearly two orders of magnitude higher than graphene. The enhanced transport originates from oxygen functional groups that distort the graphene lattice and create abundant active sites for proton passage. These findings highlight how chemical functionalization can be harnessed to boost proton transparency of 2D crystals without sacrificing gas impermeability, offering pathways for advanced proton exchange membranes. 

Proton and molecular permeation through the basal plane of monolayer graphene oxide,

Nature Communications 14, 7756 (2023). 

⭕ Transfer-free growth of high-quality monolayer graphene

In this work, we report on a simple rapid thermal treatment method for the fast and direct growth of high-quality, large-scale monolayer graphene on a SiO2/Si substrate from solid carbon sources. The stack structure of a solid carbon layer/copper film/SiO2 is adopted. The copper film does not only act as an active catalyst for the carbon precursor but also serves as a “filter” that prevents premature carbon dissolution, and thus, contributes to graphene growth on the SiO2 surface. The produced graphene exhibits a high carrier mobility of up to 3000 cm2 V−1 s−1 at room temperature and standard half-integer quantum oscillations at liquid-helium temperatures.

A fast transfer-free synthesis of high-quality monolayer graphene on insulating substrates by a simple rapid thermal treatment,

Nanoscale 8, 2594-2600 (2016). featured on the cover

⭕ Sliding ferroelectric devices based on marginally twisted 2D semiconductors

Robust room-temperature ferroelectricity was reported in marginally twisted MoS2 heterostructures, arising from broken inversion symmetry and interfacial charge transfer at the twisted bilayer interface. In this work, I contribute marginally twisted bilayer (monolayer+monolayer) MoS₂ ferroelectric devices, which exhibit pronounced hysteresis behavior of the conductivity when tuning the gate voltages (shown in the right figure). It is the first semiconducting sliding ferroelectric field-effect transistor that has ever been reported.

Interfacial ferroelectricity in marginally twisted 2D semiconductors,

Nature Nanotechnology 17, 390–395 (2022).