Hexagonal rare-earth manganites as promising photovoltaics and light polarizers

Lin

et al. 2017

Phys. Rev. Materials

Self Cite

CaOFeS is a semiconducting oxysulfide with polar layered triangular structure. Here a comprehensive theoretical study has been performed to reveal its physical properties, including magnetism, electronic structure, phase transition, magnetodielectric effect, as well as optical absorption. Our calculations confirm the Ising-like G-type antiferromagnetic ground state driven by the next-nearest neighbor exchanges, which breaks the trigonal symmetry and is responsible for the magnetodielectric effect driven by exchange striction. In addition, a large coefficient of visible light absorption is predicted, which leads to promising photovoltaic effect with the maximum light-to-electricity energy conversion efficiency up to 24.2%.

“…6(b)). Furthermore, the inherent polar structure may be advantaged for separation of photogenerated electron-hole pairs, which is also expected in ferroelectric materials [28,29,31].…”

Section: Optical Absorption and Photovoltaic Effectmentioning

confidence: 99%

Section: Optical Absorption and Photovoltaic Effectmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Exchange striction driven magnetodielectric effect and potential photovoltaic effect in polar CaOFeS

Lin

et al. 2017

Phys. Rev. Materials

Self Cite

“…6(b ], where the I 0 is the standard AM 1.5G solar spectrum, α ⊥ and α ∥ are the absorption coefficient and the L is the absorber thickness. 40, 41 An arrow points from each curve to a number that represents the result of the integration of that curve; this corresponds to the absorption power (in W/m 2 ).…”

Section: (G) 2(h) 2(i)mentioning

confidence: 99%

“…40, 41 Here we used typical absorber thickness of L = 500 nm, because that such absorber thickness is often used in the experiments. 13,17,42 For α(E), it is derived from weighted average of absorption coefficient as α(E) = (α ⊥ + 2α ∥ )/3.…”

Section: (G) 2(h) 2(i)mentioning

confidence: 99%

Electronic structure and optical properties of Cs2AX2′X4 (A=Ge,Sn,Pb; X′,X=Cl,Br,I)

Wang

Shi

2015

AIP Advances

We studied the crystal structures, electronic structures and optical properties of Cs2AX2′X4 (A=Ge,Sn,Pb; X′, X=Cl, Br, I) compounds using the first-principles calculation. Our optimized structures agree well with experimental and theoretical results. Band structure calculations, using the modified Becke-Johnson (mBJ) potential method, indicate that these compounds (with the exception of Cs2PbX2′I4) are semiconductors with the direct band gap ranging from 0.36 to 4.09 eV. We found the compounds Cs2GeBr2I4, Cs2GeCl2I4, Cs2GeI2Br4, Cs2SnI6, and Cs2SnBr2I4 may be good candidates for lead-free solar energy absorber materials.

Advanced Optical Materials

Intrinsic Strong Linear Dichroism of Multilayered 2D Hybrid Perovskite Crystals toward Highly Polarized‐Sensitive Photodetection

Liu

et al. 2019

to the polarized-light and thus enable a highly efficient photodetection. [13][14][15][16][17][18] The mainstream of this field is dominated by inorganic 2D systems, such as metallic graphene, black phosphorus, and transition metal dichalcogenides (e.g., MoS 2, ReS 2 , and GeSe 2 ). [5,6,[19][20][21][22][23] However, their device assembling often suffers from the complicated, high-cost and energy-intensive integration; it is particularly difficult to obtain bulk high-quality crystals. [24][25][26][27] All these unfavorable issues stimulate the urgent demand for exploring new linear dichroism systems as the feasible alternatives or supplements to the inorganic counterparts.Organic-inorganic 2D hybrid perovskites, as a subclass of 3D cubic prototype, have been explored for multiple applications, benefiting from their unique physical merits including structural flexibility, superior stability, and quantum-confined effects, etc. [28][29][30][31][32][33][34][35][36] From the structural perspective, organic components and inorganic frameworks feature an alternative arrangement, which resembles the quantum-confined architecture and therefore manifests the strongly anisotropic characteristics. [13,14] Particularly, this configuration anisotropy closely relates to the electronic structure and dielectric properties that exert a great influence on their optical absorption. The absorption coefficients along different crystallographic axes can be achieved from imaginary part and real part of the dielectric functions. That is, the real and imaginary parts of the complex refractive index are highly dependent on crystalline directions, thus corresponding to optical anisotropy of 2D hybrid perovskites (i.e., linear dichroism). [8] Definitely, such intrinsic linear dichroism of 2D hybrid perovskites affords infinite promises for polarized-light detections. For instance, (PEA) 2 PbI 4 exhibits linear dichroism deriving from the absorption disparity under polarized light along three crystallographic axis directions. [8] More recently, high-performance polarized-light detectors were constructed using 2D hybrid perovskite of (BA) 2 (MA)Pb 2 Br 7 , [18] based on the strong anisotropy of crystal architecture and optical absorption. In this context, it is proposed that intrinsic linear dichroism of 2D hybrid perovskites provides a great opportunity to achieve new candidates for polarized-light detection. Linear dichroism of 2D materials is brought into practical operation of polarized light detection; currently, organic-inorganic 2D hybrid perovskites with the linear dichroic nature offers immense potentials within this portfolio.Here, a newly tailored 2D hybrid perovskite, (iBA) 2 (MA)Pb 2 I 7 (1, where MA + is methylammonium and iBA + is n-isobutylammonium) is investigated, adopting a highly anisotropic bilayered perovskite motif that results in strong crystallographic-dependence of linear dichroism. Both the absorption spectra (300-650 nm) and polarized-sensitive activities of 1 exhibit the distinctive anisotropic characteristics. Con...