With their outstanding mechanical and magnetic characteristics, two-dimensional magnetic materials have attracted wide attentions in the field of nanoelectromechanics and spintronics. By tuning the mechanical resonance with external knobs, such as strain, electric and magnetic control, nanoelectromechanical sensors with novel functionalities have been successfully demonstrated. Here, we investigate the mechanical properties of the suspended membranes with few-layered antiferromagnetic material CrOCl. The results show that the Young’s modulus of CrOCl resonators is ~137.29 GPa by using a static detection method. Below the transition temperature T_N, the mechanical resonance is found to strongly depend on the magnetic fields with an enormous blueshift of ~3.1% in the magnetic-field-induced phase transition. In addition, we also found that the variation of strain of system $∆ϵ$ was about 1.5 × 10⁻³ during the transition. Our study shows the great potential of two-dimensional magnetic materials in future nanoelectronic applications.

Two-dimensional (2D) magnetic semiconductors exhibit unique combination of electronic and magnetic properties, holding great promise in potential applications such as spintronics and magneto-optics. However, many of them are air-sensitive, and their properties can be significantly altered upon exposure to air. Here, we showed an optical spectroscopic investigation of the effects of air-degradation on few-layered van der Waals (vdW) magnetic semiconductor Cr₂Ge₂Te₆. It was found that although the partially degraded few-layered Cr₂Ge₂Te₆ showed a significant Raman redshift and a split of E_g peak at room temperature, the magneto-optic Kerr hysteresis loop can remain largely unchanged below the Curie temperature. Temperature-dependent Raman measurements further revealed characteristic blueshifts of phonon energy, which were associated with the ferromagnetic phase transition in partially degraded Cr₂Ge₂Te₆, in agreement with Kerr measurements. Our results provide an optical spectroscopic insight into the air-instability of 2D magnetic semiconductors, and contribute to a better understanding of the relationship between phonon modes and long-range spin order at the presence of defects in ultra-thin vdW magnetic semiconductors.

Field effect transistors based on few-layered van der Waals transition metal halide (TMH) Nb₃Cl₈ are studied in this work. Few-layered Nb₃Cl₈ exhibits typical N-type semiconducting behavior controlled by a Si gate, with the electrical signal enhancing as the thickness increases from 4.21 nm to 16.7 nm. Moreover, we find that the tunability of few-layered Nb₃Cl₈ FETs’ electrical transport properties can be significantly augmented through the use of an ionic liquid gate (or electrical double layer, EDL). This enhancement leads to a substantial increase in the on–off ratio by approximately a factor of ${10}^2$, with the transfer curve modulated into a bipolar fashion. The emergence of such bipolar tunable characteristics in Nb₃Cl₈ FETs serves to enrich the electronic properties within the transition metal halide family, positioning Nb₃Cl₈ as a promising candidate for diverse applications spanning transistors, logic circuits, neuromorphic computing and spintronics.