Cannizzarite is a naturally occurring mineral formed by van der Waals (vdW) stacking of alternating layers of PbS-like and Bi2S3-like two-dimensional (2D) materials. Although the PbS-type and Bi2S3-type 2D material layers are structurally isotropic individually, the forced commensuration between these two types of layers while forming the heterostructure of cannizzarite induces strong structural anisotropy. Here we demonstrate the mechanical exfoliation of natural cannizzarite mineral to obtain thin vdW heterostructures of PbS-type and Bi2S3-type atomic layers. The structural anisotropy induced anisotropic optical properties of thin cannizzarite flakes are explored through angle-resolved polarized Raman scattering, linear dichroism, and polarization-dependent anisotropic third-harmonic generation. Our study establishes cannizzarite as a new natural vdW heterostructure-based 2D material with highly anisotropic optical properties for realizing polarization-sensitive linear and nonlinear photonic devices for future on-chip optical computing and optical information processing.
Anisotropic photonic materials with linear dichroism are crucial components in many sensing, imaging, and communication applications. Such materials play an important role as polarizers, filters, and waveplates in photonic devices and circuits. Conventional crystalline materials with optical anisotropy typically show unidirectional linear dichroism over a broad wavelength range. The linear dichroism conversion phenomenon has not been observed in crystalline materials. The investigation of the unique linear dichroism conversion phenomenon in quasi‐1D hexagonal perovskite chalcogenide BaTiS3is reported. This material shows a record level of optical anisotropy within the visible wavelength range. In contrast to conventional anisotropic optical materials, the linear dichroism polarity in BaTiS3makes an orthogonal change at an optical wavelength corresponding to the photon energy of 1.78 eV. First‐principles calculations reveal that this anomalous linear dichroism conversion behavior originates from the different selection rules of the parallel energy bands in the BaTiS3material. Wavelength‐dependent polarized Raman spectroscopy further confirms this phenomenon. Such a material, with linear dichroism conversion properties, could facilitate the sensing and control of the energy and polarization of light, and lead to novel photonic devices such as polarization‐wavelength selective detectors and lasers for multispectral imaging, sensing, and optical communication applications.
more » « less- PAR ID:
- 10460295
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 31
- Issue:
- 33
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
more » « less
Abstract -
more » « less
Abstract Lengenbachite is a naturally occurring layered mineral formed with alternating stacks of two constituent PbS-like and M2S3-like two-dimensional (2D) material layers due to the phase segregation process during the formation. Here, we demonstrate to achieve van der Waals (vdW) heterostructures of lengenbachite down to a few layer-pair thickness by mechanical exfoliation of bulk lengenbachite mineral. The incommensurability between the constituent isotropic 2D material layers makes the formed vdW heterostructure exhibit strong in-plane structural anisotropy, which leads to highly anisotropic optical responses in lengenbachite thin flakes, including anisotropic Raman scattering, linear dichroism, and anisotropic third-harmonic generation. Moreover, we exploit the nonlinear optical anisotropy for polarization-dependent intensity modulation of the converted third-harmonic optical vortices. Our study establishes lengenbachite as a new natural vdW heterostructure-based 2D material with unique optical properties for realizing anisotropic optical devices for photonic integrated circuits and optical information processing.
-
more » « less
Abstract 2D anisotropic materials, such as black phosphorus, ReS2, and GaTe, have been shown to exhibit exciting direction‐ and polarization‐sensitive material properties. Highly crystalline chemical‐vapor‐transport‐grown ZrS3crystals exhibit large optical‐absorption‐coefficient anisotropy, which doubles under resonance conditions. The observed optical anisotropy manifests itself in angle‐resolved photocurrent density polar plots with dichroic ratio (
I pb/I pa) of 1.73 excited by a laser source of λ = 450 nm and 1.14 by λ = 532 nm. The optical absorption and electronic dichroic response are fully explained through detailed band structure and polarization‐sensitive optical‐absorption‐spectrum calculations. Not only is the family of 2D anisotropic semiconductors expanded into Zr‐based trichalcogenides but fundamental insights on how crystalline anisotropy, optical absorption dichroism, and generated photocurrents are interrelated in van der Waals Zr‐based trichalcogenides materials are also provided. -
Abstract The design and formation of van der Waals (vdW) heterostructures with different two-dimensional (2D) materials provide an opportunity to create materials with extraordinary physical properties tailored toward specific applications. Mechanical exfoliation of natural vdW materials has been recognized as an effective way for producing high-quality ultrathin vdW heterostructures. Abramovite is one of such naturally occurring vdW materials, where the superlattice is composed of alternating Pb 2 BiS 3 and SnInS 4 2D material lattices. The forced commensuration between the two incommensurate constituent 2D material lattices induces in-plane structural anisotropy in the formed vdW heterostructure of abramovite, even though the individual 2D material lattices are isotropic in nature. Here, we show that ultrathin layers of vdW heterostructures of abramovite can be achieved by mechanical exfoliation of the natural mineral. Furthermore, the structural anisotropy induced highly anisotropic vibrational and optical responses of abramovite thin flakes are demonstrated by angle-resolved polarized Raman scattering, linear dichroism, and polarization-dependent third-harmonic generation. Our results not only establish abramovite as a promising natural vdW material with tailored linear and nonlinear optical properties for building future anisotropic integrated photonic devices, but also provide a deeper understanding of the origin of structural, vibrational and optical anisotropy in vdW heterostructures.more » « less
-
more » « less
Abstract Nagyágite is a naturally occurring layered van der Waals heterostructure composed of alternating layers of [Pb(Pb,Sb)S2] and [(Au,Te)], where the component lattices are commensurately modulated. The weak van der Waals stacking between the heterolayers facilitates mechanical exfoliation. Due to its monoclinic crystal structure, nagyágite exhibits structural anisotropy which induces strong optical anisotropy. Here, the anisotropic optical properties of ultrathin nagyágite flakes mechanically exfoliated from a natural mineral are demonstrated through angle‐resolved polarized Raman scattering, linear dichroism, and polarization‐dependent anisotropic third‐harmonic generation. The study establishes nagyágite as a new type of natural van der Waals heterostructure based 2D material, which can be exploited for realizing ultrathin anisotropic optical devices for future on‐chip photonic integrated circuits.
