Layer-Dependent Phonons, Excitons, and Magneto-Optical Phenomena in CrSBr: A Mini Review

Corresponding authors*: [email protected], [email protected]

Abstract

Keywords: CrSBr, magnetic anisotropy, spin-phonon coupling, Frenkel excitons, Wannier–Mott excitons

Introduction

Engineering magnetism and excitonic phenomena through dimensionality control in van der Waals (vdW) solids is a rapidly advancing field in condensed matter physics. Reducing the crystal thickness from bulk to few-layer and monolayer forms systematically modulates the interactions among the spin, charge, lattice, and excitonic degrees of freedom, enabling access to emergent quantum states and many-body effects beyond thermodynamic equilibrium [1, 2, 3, 4]. Two-dimensional magnetic materials have catalyzed transformative advances in multiple technological domains, including spin-filter tunneling, magnetic memory architectures, valleytronics platforms, excitonic engineering, and quantum photonics [3, 5]. This is fundamentally because their reduced dimensionality amplifies the role of interfacial and interplane interactions while simultaneously suppressing competing perturbations that typically mask quantum effects in bulk materials [1, 3, 6, 7, 8, 9, 10, 11].

Among these, chromium sulfur bromide has emerged as a distinguished system owing to its intrinsic air stability, semiconducting nature, pronounced in-plane anisotropy, and robust A-type antiferromagnetic ordering with a Néel temperature near 132 K. Unlike chromium trihalides ($\mathrm{CrX}_3$, where $X = \mathrm{Cl}$, $\mathrm{Br}$, or $\mathrm{I}$), which often suffer from low ordering temperatures and environmental instability [12, 13, 14, 15]. CrSBr combines practical stability, strong magnetic anisotropy, and a quasi-one-dimensional crystal structure. This unique combination results in highly anisotropic magnetic and optical properties that evolve systematically with the number of layers [16, 17, 18, 19]. Recent experimental and theoretical advances have elucidated the layer-dependent evolution of the magnetism, vibrational dynamics, and excitonic landscape of CrSBr [7, 20, 21, 22].

Key phenomena include interlayer spin reorientation, strong spin-phonon coupling, and the coexistence of Frenkel and Wannier–Mott excitons, which collectively link dimensionality to coupled magnetic and optical responses [16, 17, 18, 19, 23, 24, 25]. Therefore, this mini review critically examines recent progress in understanding the crystal structure, magnetic anisotropy, interlayer magnetic interactions, vibrational properties, and excitonic behavior of CrSBr, from bulk crystals to monolayer limits. We emphasize the fundamental mechanisms driving layer-dependent magneto-optical responses and their implications for spintronic, magneto-optical, and quantum photonic applications.

Crystal Structure and Structural Anisotropy

Chromium sulfur bromide crystallizes in an orthorhombic FeOCl-type structure (space group Pmmn), featuring weakly coupled layers stacked along the crystallographic $c$-axis via van der Waals (vdW) interactions (fig:1a) [26]. Each monolayer consists of distorted $\mathrm{CrS}_{4}\mathrm{Br}_{2}$ octahedra arranged in a highly anisotropic rectangular lattice. These octahedra are connected through edge-sharing along the $a$-axis and corner-sharing along the $b$-axis, establishing an intrinsically anisotropic bonding environment that strongly influences the electronic, magnetic, vibrational, and optical properties of the material [27]. The $\mathrm{Cr}^{3+}$ ions coordinate with four $\mathrm{S}^{2-}$ and two $\mathrm{Br}^{-}$ anions, with Br atoms occupying the outermost atomic layers. These bromine atoms play a critical role in mediating the interlayer coupling and vibrational interactions. The vdW gaps between adjacent layers facilitate mechanical exfoliation down to the monolayer limit while preserving the lattice symmetry [26, 28]. First-principles density functional theory (DFT) calculations, supported by low-temperature X-ray and neutron diffraction experiments, confirmed the structural stability and lattice parameters ($a = 3.52$ Å, $b = 4.74$ Å, $c = 7.91$ Å) of CrSBr, which closely matched the experimental values [29, 30, 31]. The weak vdW interlayer forces ensure that the few-layer and monolayer samples retain the bulk crystallographic framework, preserving the pronounced anisotropy essential for the observed layer-dependent phenomena [29]. Beyond the experimentally confirmed AA-0 stacking, theoretical studies have identified several high-symmetry bilayer configurations, namely, AA-1, AB-0, and AB-1 (fig:1b)–(fig:1e), which differ in terms of their relative lateral displacements and symmetry operations [26]. Despite these variations, DFT consistently predicts the A-type antiferromagnetic (AFM) state as the energetically favored magnetic configuration, characterized by ferromagnetic spin alignment within layers coupled antiferromagnetically between adjacent layers, resulting in alternating spin orientations along the $c$-axis [32]. This robustness highlights the intrinsic magnetic stability of CrSBr and its suitability for low-dimensional spintronic applications [32, 33].

The microscopic origin of the magnetic anisotropy and interlayer coupling arises from multiple intralayer super-exchange pathways mediated by the sulfur and bromine atoms (Figure 1f–h) [29]. These pathways, denoted $J_1$, $J_2$, and $J_3$, are defined by distinct Cr–S/Br–Cr bond angles ($\alpha$, $\beta$, $\gamma$, and $\delta$) and specific orbital hybridizations, governing the balance between ferromagnetic intralayer and antiferromagnetic interlayer interactions. The edge-sharing geometry along the a-axis facilitates a strong ferromagnetic superexchange via the direct overlap of Cr 3d orbitals mediated predominantly by S 3p orbitals, forming quasi-one-dimensional magnetic chains. In contrast, corner-sharing connectivity along the b-axis introduces an anisotropic exchange coupling, which significantly contributes to the pronounced in-plane magnetic anisotropy. Bromine atoms positioned in the outermost layers mediate superexchange pathways that modulate the interlayer magnetic coupling and vibrational interactions. This bromine-mediated superexchange plays a pivotal role in linking structural anisotropy to magnetic ordering and magneto-optical response. The interplay among these exchange pathways underpins the stability of the A-type AFM ground state and governs the layer-dependent evolution of the spin reorientation, spin-phonon coupling, and excitonic phenomena characteristic of CrSBr [29, 31, 34].

Layer-Dependent Interlayer Magnetism and Spin Reorientation

A-type AFM ordering in CrSBr persists down to the 2L limit, establishing it as a prototypical system for investigating thickness-dependent magnetism in two-dimensional materials [35, 36, 37, 38]. First-principles calculations have revealed that monolayer CrSBr favors a ferromagnetic ground state, whereas multilayer structures stabilize an A-type AFM configuration with the magnetic easy axis aligned along the crystallographic b-axis [18, 39]. Thus, increasing the number of layers beyond the monolayer limit drives a transition to the A-type AFM state, which is characterized by ferromagnetic intralayer spin alignment and antiferromagnetic coupling between adjacent layers. This evolution highlights the crucial role of interlayer exchange interactions in stabilizing the magnetic ground state of the multilayers. As depicted in fig:2a and fig:2b, both the nearest-neighbor interlayer exchange interaction ($J$) and magnetic anisotropy energy ($K$) strongly depend on the layer number. Importantly, these parameters exhibited an odd-even oscillatory pattern, reflecting the interplay between magnetic anisotropy, interlayer exchange coupling, and Zeeman energy under applied magnetic fields [18].

Applying a magnetic field along the easy b-axis induces a spin-flop transition governed by the competition among the antiferromagnetic interlayer exchange (which favors antiparallel spins), magnetic anisotropy energy (which stabilizes spins along the easy axis), and Zeeman energy (which tends to align spins with the field) [40, 41]. The system undergoes a transition from a collinear AFM state to a noncollinear spin configuration once the Zeeman energy exceeds the anisotropy energy and approaches the interlayer exchange interaction energy. Both the critical field ($H_\mathrm{c}$), which marks the onset of the spin-flop, and the saturation field ($H_\mathrm{s}$), which corresponds to the full spin alignment, depend strongly on the number of layers ([]{#fig:2}c). This behavior demonstrates the tunability of the interlayer magnetic coupling in atomically thin CrSBr [18].

Monte Carlo simulations employing an antiferromagnetic linear-chain model successfully reproduce the experimentally observed magnetic phase diagrams and reveal distinct spin-reorientation behaviors between even- and odd-layer CrSBr samples (fig:2d–fig:2k) [18]. In the even-layer samples, the intermediate spin-flop phase exhibited a symmetric noncollinear configuration, with opposing layers rotating by equal angles relative to the magnetic field direction. Conversely, odd-layer crystals possess uncompensated magnetization, resulting in an asymmetric noncollinear spin texture. This asymmetry causes the equivalent layers to adopt inequivalent spin orientations, thereby breaking the spin symmetry in a thickness-dependent manner. This odd-even effect correlates with the experimentally observed differences in the magnetotransport and magnetic responses of ultrathin CrSBr.

The spin reorientation that varies with the layer thickness highlights the subtle balance among the interlayer exchange interactions, magnetic anisotropy, and Zeeman energy, which collectively shape the magnetic phase diagram of CrSBr. The appearance of unique magnetic configurations in samples with odd and even numbers of layers illustrates how dimensionality significantly affects both the magnetic ground state and spin dynamics influenced by external fields. These magnetic phases, which depend on the thickness, provide a fundamental basis for comprehending the interaction between the magnetic order and other degrees of freedom, such as lattice vibrations and optical excitations, which are discussed in the following sections.

Vibrational Properties and Spin–Phonon Coupling in CrSBr

The coupling between lattice vibrations and magnetic order is a fundamental characteristic of low-dimensional magnetic materials and critically influences their electronic and optical properties [42, 43, 44, 45, 46, 47]. In CrSBr, this interplay is especially pronounced owing to its quasi-one-dimensional crystal structure, strong in-plane anisotropy, and layered antiferromagnetic ground state. The reduced dimensionality and anisotropic bonding environment result in highly directional vibrational, electronic, and optical responses, positioning CrSBr as an excellent platform for studying the interactions among the spin, lattice, electronic, and excitonic degrees of freedom [48, 49]. Raman scattering spectroscopy is a particularly effective tool for probing these interactions because of its sensitivity to crystal symmetry, magnetic order, and electron–phonon coupling [50, 51, 52].

Early evidence of strong spin-phonon coupling in CrSBr was revealed by temperature-dependent Raman measurements performed across an antiferromagnetic transition. Upon cooling below the Néel temperature ($T_{\mathrm{N}} \approx132$ K), several Raman-active phonon modes displayed anomalous frequency shifts, linewidth variations, and intensity changes that cannot be attributed solely to anharmonic lattice effects (fig:3a and fig:3b) [48]. Additionally, new Raman features appeared below $T_{\mathrm{N}}$, indicating crystal symmetry modifications associated with the onset of magnetic ordering. These findings demonstrate a strong coupling between the lattice dynamics and antiferromagnetic correlations. Ab initio phonon calculations successfully replicated the experimental spectra and confirmed that the magnetic phase significantly affected the vibrational response of the spectra [53]. Consequently, the resulting Raman fingerprints serve as sensitive spectroscopic markers for differentiating between magnetic phases and monitoring the evolution of the magnetic order [53, 54, 55].

The vibrational spectrum of CrSBr strongly depends on the layer thickness. Raman scattering studies, performed with excitation energies in the vicinity of the electronic transitions of CrSBr, revealed systematic shifts in phonon frequencies and changes in their intensities in samples ranging from monolayers to bulk [54, 55]. Specifically, $A^{1}_{g}$ and $A^{2}_{g}$ modes exhibited gradual redshifts as the number of layers decreased, whereas the $A^{3}_{g}$ mode remained almost constant. This contrasting behavior reflects the anisotropic nature of lattice vibrations and weak interlayer coupling, which are typical of van der Waals materials. Because bromine atoms reside in the outermost atomic layers, they mediate interlayer vibrational interactions that significantly influence the phonon spectrum. As the thickness increased, the restoring forces associated with certain lattice vibrations increased, causing the observed stiffening of the vibrational modes in the multilayer samples [56, 57]. Moreover, Raman measurements performed under excitation energies resonant with CrSBr excitonic transitions revealed additional defect-related vibrational features, underscoring the sensitivity of the phonon spectrum to local structural perturbations and the local magnetic environment (fig:3c and fig:3d) [55].

Recent polarization-resolved Raman studies have further elucidated the anisotropic nature of the vibrational response of CrSBr. Notably, the $A^{2}_{g}$ mode near $244$ $\mathrm{cm}^{-1}$ exhibited an approximately $90^\circ$ polarization rotation as a function of the excitation energy and layer thickness [58]. While the $A^{1}_{g}$ and $A^{3}_{g}$ Modes remain predominantly polarized along the crystallographic b-axis, the $A^{2}_{g}$ mode rotates between the a- and b-axes depending on the excitation wavelength and can be represented in Figure 3. This behavior cannot be solely attributed to lattice symmetry and instead reflects the impact of anisotropic electronic transitions on the Raman scattering process [59, 60]. The pronounced excitation energy dependence of the Raman anisotropy implicates resonant excitonic states, indicating that the vibrational response of CrSBr is closely coupled to its electronic structure.

Temperature-dependent polarization measurements further underscore the role of excitonic effects in this system. Pronounced changes in the Raman anisotropy near the magnetic transition reveal a direct correlation between the magnetic ordering and optical selection rules (Figure 3 g- i) [61]. Combined analysis of the Raman and optical absorption data suggests that excitonic resonances modify electron–phonon interactions, thereby increasing the phonon sensitivity to the magnetic order. Consequently, the Raman response of CrSBr is governed not only by spin–phonon coupling but also by a complex interplay involving excitonic, electronic, and vibrational degrees of freedom. This integrated perspective situates CrSBr within a select group of layered magnetic semiconductors, where the magnetic order, lattice vibrations, and excitonic states are strongly interdependent. The transition from predominantly phononic features at elevated temperatures to coupled spin-phonon and exciton–phonon phenomena at low temperatures establishes a crucial framework for interpreting the optical properties discussed in the subsequent sections, where excitonic effects and magneto-optical responses are dominant.

Thickness-Dependent Excitonic Landscape and Magneto-Optical Response of CrSBr

The strong interplay among the electronic, magnetic, and excitonic degrees of freedom in CrSBr results in a complex and rich optical response that is distinct from that of conventional van der Waals semiconductors such as $\mathrm{CrI}_{3}$, $\mathrm{CrCl}_{3}$, and $\mathrm{LnSe}_{2}$. In CrSBr, the excitonic properties are not solely determined by dielectric screening and quantum confinement but are significantly modulated by the magnetic order and interlayer electronic coupling. As the thickness increases from the monolayer limit to the bulk, the photoluminescence (PL) spectrum and its magnetic-field dependence undergo substantial changes, revealing a hierarchy of excitonic states that evolve with dimensionality [36, 62].

Initial PL studies on atomically thin CrSBr demonstrated robust excitonic emission at room temperature from 1L to trilayer (3L) samples, with emission peaks near 1.28–1.29 eV and absorption resonances of approximately 1.36–1.37 eV, corresponding to a Stokes shift of approximately 80 meV [17]. These transition energies align well with the theoretical electronic band structure predictions, confirming the semiconducting nature of CrSBr [63]. Temperature-dependent measurements showed the expected blue shift of excitonic emission upon cooling, which is characteristic of direct-gap semiconductors[64, 65]. However, deviations from this trend coincide with the onset of magnetic ordering, indicating a strong coupling between the excitonic states and the magnetic ground state [23].

Magneto-PL experiments revealed a pronounced thickness dependence of the magnetic field sensitivity. The monolayer CrSBr exhibited negligible magnetic-field effects on its PL spectrum, whereas the bilayer 2L CrSBr displayed significant field-induced spectral shifts and modifications in the excitonic lineshape (Figure 4a–c) [23]. This contrast highlights the critical role of interlayer electronic coupling in governing magneto-excitonic interactions and demonstrates that dimensionality fundamentally alters the coupling between excitons and the magnetic order.

At low temperatures (4 K), the PL spectra primarily consist of two bands, B1 and B2 (Figure 4d) [64]. The lower-energy B1 band, centered near 1.23 eV, dominates thicker flakes and bulk crystals but diminishes as the two-dimensional limit is approached. This band is attributed to impurity-related states, likely associated with sulfur and bromine vacancies [64, 66]. Conversely, the higher-energy B2 band persists across all thicknesses and is assigned to intrinsic exciton recombination [64, 66, 67, 68]. Whereas the 1 L and 2 L samples exhibited a single dominant excitonic feature (P1*), the thicker samples exhibited multiple excitonic transitions (P1, P2, P3, and P4) at lower energies. Notably, the P4 transition emerged from trilayer thickness onward and demonstrated exceptional magnetic field sensitivity, reflecting a strong coupling to interlayer magnetic correlations. The PL spectrum under an external magnetic field $\mathbf{B}$ for tri-layer and 15-layer CrSBr can be seen in Figures 4e and 4f [64].

Magnetic correlation spectroscopy further reveals the complexity of the excitonic landscape [69]. Excitation power-dependent measurements confirmed the excitonic origin of most optical transitions through linear scaling. However, several emission lines exhibited saturation at higher powers, indicative of localized excitonic states confined within shallow trapping potentials [70]. Temperature-dependent studies have shown that these localized excitons vanish above approximately 16 K owing to thermal activation, permitting carriers to escape confinement and quenching the associated emission peaks [71, 72]. The magnetic-field-dependent data revealed significant spectral weight redistribution among excitonic transitions, emphasizing the interplay between magnetic correlations and exciton localization.

Additional insights have been gained from studies on hBN-encapsulated few-layer CrSBr. The monolayers displayed a broad excitonic feature near 1.34 eV, whereas the bilayers and thicker samples exhibited additional narrow emission lines with linewidths of a few meV. The behavior of the PL peaks in this study is shown in Figure 5a [73]. A high-energy excitonic state (Xh) appears in bilayers and splits into two distinct transitions (Xh and Xh') in trilayers and tetralayers, separated by approximately $5\,\mu\mathrm{eV}$. These observations indicate a progressive reconstruction of the excitonic spectrum driven by an increase in interlayer coupling, reinforcing the strong correlation between dimensionality and optical response [74, 75].

Temperature-dependent photoluminescence measurements further confirmed that as the temperature increased, the excitons localized in shallow trapping potentials acquired sufficient thermal energy to escape confinement, leading to the disappearance of the corresponding emission peaks [76]. At elevated temperatures ($\sim100$ K), only selected emission peaks, such as XB, XD, and X3, persisted (Figure 5b, Figure 5c). The dependence of the emission peaks on the applied magnetic fields was also investigated, demonstrating that the excitonic emission of CrSBr is highly sensitive to magnetic fields. In the absence of a magnetic field, all emission peaks are visible (Figure 5d, Figure 5e), whereas many peaks (P1, P2, P3, XD, X5, and X4) vanish upon applying magnetic fields of $\pm0.5$ T [69].

A particularly remarkable recent development is the discovery of excitonic duality in CrSBr. Magneto-optical studies have revealed the coexistence of localized Frenkel-like excitons and delocalized Wannier-Mott excitons in the same material [77, 78]. This coexistence stems from the strongly anisotropic electronic structure of CrSBr, which offers a unique opportunity to simultaneously investigate two fundamentally distinct excitonic regimes. These exciton families exhibit markedly different responses to magnetic fields: Wannier-Mott excitons display pronounced spectral shifts and intensity redistribution, whereas Frenkel excitons remain largely localized with minimal field dependence. Complementary studies spanning monolayer to trilayer CrSBr revealed a striking odd-even layer dependence in the magneto-optical behavior; 1L and 3L samples exhibited similar characteristics, whereas 2L CrSBr displayed qualitatively distinct excitonic responses [3]. The representative magneto-PL and PL excitation (PLE) spectra of few-layer CrSBr acquired under tunable out-of-plane magnetic fields are shown in Figure 5f–Figure 5h. Figure 5f shows two-dimensional color maps of the PLE intensity as a function of excitation and detection energies for trilayer (3L) CrSBr, measured at magnetic fields ranging from 0 to 3.0 T. In the absence of an applied field, two distinct excitonic signatures were readily resolved: the high-energy B-exciton excitation band near 1.78 eV and a narrow A-series detection peak fixed at $\sim1.36$ eV. With increasing magnetic field, the integrated PLE signal of the $A^{\prime}$ subband (arising from bound or intervalley excitons bridging the B excitation manifold and A detection peak) increased drastically and monotonically, whereas the excitation and emission peak energies exhibited negligible magnetic-field-induced shifts.

Furthermore, the complementary stacked magneto-PL and magneto-PLE spectra shown in Figure 5g quantify the field-dependent evolution of the spectral intensity. The left-hand PL panel in Figure 5g shows the emission detected at the A exciton energy, revealing the progressive suppression of the $A^{\prime}$ shoulder peak relative to the main A peak as the magnetic field increased.

The PLE in the right panel of Figure 5g shows the monitoring absorption at the A detection channel, showing pronounced amplification of the B-exciton excitation resonance with increasing external magnetic field. Figure 5h further shows the critical effect of layer thickness on the intrinsic PL peak shape. A primary source of peak profile reshaping between 1L, 2L and 3L studies.

Copyright 2025, American Chemical Society. (f) False-color map of the PLE spectroscopy measured on 3L CrSBr around the A exciton for different values of magnetic field ranging from 0 to 3T. (g) PL and PLE spectra of 1L, 2L, and 3L CrSBr measured at 5 K under 2.41 eV excitation laser. (h) PL spectra of 3L CrSBr recorded at the B exciton resonance, demonstrating shifts in the B exciton energies with increasing applied magnetic field. Reproduced with permission. [3] Copyright 2025, IOP Science.

For 1L and 3L, the A′ low-energy shoulder is weak and broad, with the leading A exciton peak, while 2L exhibits a moderately intensified A′ feature, but no A peak is observed in the spectrum. Thickness-dependent quantum confinement controls interlayer orbital hybridization and exciton binding energies, modifying the relative oscillator strength of the A′ sub-exciton state without shifting that of the central exciton state. Collectively, this study demonstrates that the extrinsic measurement conditions and intrinsic material dimensionality dominate the variable PL peak line shapes and intensity ratios [3].

The evolution of narrow A and A′ excitonic resonances under a magnetic field highlights that dimensionality not only shapes the excitonic spectrum but also fundamentally alters the exciton-magnetic-order interactions. Collectively, these studies demonstrate the progressive evolution of the excitonic landscape from relatively simple emission in the monolayer limit to a complex manifold of magnetically sensitive excitonic states in multilayer and bulk CrSBr. The strong dependence of excitonic transitions on thickness, magnetic ordering, interlayer coupling, and external magnetic fields underscores the intimate relationship between dimensionality and optical response, establishing excitons as highly sensitive probes of correlated electronic and magnetic phenomena in layered magnetic semiconductors.

Future Perspectives, Challenges, and Emerging Technological Applications

CrSBr is a remarkable early vdW magnet owing to its robust air stability and antiferromagnetic ordering up to $\sim132$ K in bulk and $\sim140$ K in ultrathin layers. Its structural anisotropy, layer-dependent magnetism, strong spin–phonon coupling, rich excitonic features, and magneto-optical response make it an ideal platform for studying spin, lattice, charge, and exciton interactions in reduced dimensions. Despite these significant advances, several critical challenges remain. A primary objective in the field of two-dimensional magnetism is to achieve magnetic ordering at or above room temperature. For CrSBr, promising strategies to achieve this goal include strain engineering, chemical substitution, electrostatic doping, and heterostructure design, which offer avenues for modulating exchange interactions and magnetic anisotropy. Tailoring super-exchange pathways through compositional modifications or leveraging proximity effects in hybrid heterostructures may enhance the magnetic ordering temperatures and stabilize novel magnetic phases.

Another important direction is the development of optically addressable magnetic functionality. Given the strong sensitivity of excitonic transitions to the magnetic order in CrSBr, optical spectroscopy has emerged as a powerful noninvasive probe of spin configurations in atomically thin layers. This capability opens pathways for integrating magnetic and optical functionalities within a single material platform, wherein magnetic states can be monitored and potentially manipulated using their excitonic signatures. Such integration holds promise for low-power information processing technologies and advances in the study of light–matter interactions in magnetic semiconductors. Beyond isolated flakes, the incorporation of CrSBr into engineered heterostructures and optical cavities represents a promising frontier. Recent discoveries of robust exciton–magnon and magneto-excitonic interactions suggest that CrSBr may host novel hybrid quasiparticles when coupled with confined photonic modes. The realization of magnetically tunable exciton-polaritons and related collective excitations could enable the exploration of nonequilibrium quantum phenomena and strongly coupled light–matter systems. Concurrently, continued progress in material synthesis, interface engineering, and device fabrication is essential to translate the intrinsic physical properties of CrSBr into viable technological applications.

In summary, CrSBr occupies a distinctive position at the nexus of two-dimensional magnetism, excitonic physics, and magneto-optics. Ongoing efforts to deepen the understanding and control of its coupled electronic, magnetic, vibrational, and optical properties are anticipated to uncover new physical phenomena and broaden the scope of applications enabled by this versatile, layered magnetic semiconductor.

Acknowledgments

This work is supported by the European Union’s Marie Skłodowska-Curie Actions under the Horizon Europe research and innovation programme (Grant No. 101204286). M.R.Molas gratefully acknowledges support from the National Science Centre, Poland (Grant No. 2022/46/E/ST3/00166 and 2023/50/O/ST3/00310).

Author Contributions

Muhammad Aftab and Chinmay Kumar Mohanty wrote the original draft of the manuscript. Zain Ashfaq and Warisha Mehmood contributed to manuscript editing and visualization. Xiaoli Wang and Clément Faugeras reviewed and edited the manuscript. Wajid Ali and Maciej R. Molas supervised the work and acquired funding. All authors reviewed and approved the final version of the manuscript.

Data Availability

Data will be made available on request.

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