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Related papers: Optical properties of cubic and rhombohedral GeTe

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Partial substitution of Fe by Ta in the hole-doped La0.5Sr0.5FeO3 decreases the electric conductivity by up to three orders of magnitude. This decrease is in immediate correlation with a decrease of the electron hole concentration and a…

Ge/Si(001) multilayer heterostructures containing arrays of low-temperature self-assembled Ge quantum dots and very thin Si$_x$Ge$_{1-x}$ layers of varying composition and complex geometry have been studied using Raman spectroscopy and…

In this work, we report the effects of calcination temperature on structural, dielectric, semiconducting and optical properties of YFeO3 nanoparticles prepared by a high energy ball milling process. The structural analysis of the X-ray…

Materials Science · Physics 2019-10-08 Chandra Bhal Singh , Dinesh Kumar , Narendra Kumar Verma , Akhilesh Kumar Singh

Atomistically detailed computational studies of nanocrystals, such as those derived from the promising lead-halide perovskites, are challenging due to the large number of atoms and lack of symmetries to exploit. Here, focusing on…

Materials Science · Physics 2022-10-05 Giulia Biffi , Yeongsu Cho , Roman Krahne , Timothy C. Berkelbach

The relationship between the luminescence at 1.9 eV and the absorption bands at 2.0 eV and at 4.8 eV were investigated in a wide variety of synthetic silica samples exposed to different gamma- and beta-ray irradiation doses. We found that…

Materials Science · Physics 2007-05-23 L. Vaccaro , M. Cannas , B. Boizot

The complex optical properties of a single crystal of hexagonal FeCrAs ($T_N \simeq 125$ K) have been determined above and below $T_N$ over a wide frequency range in the planes (along the $b$ axis), and along the perpendicular ($c$ axis)…

Strongly Correlated Electrons · Physics 2014-03-21 A. Akrap , Y. M. Dai , W. Wu , S. R. Julian , C. C. Homes

Scanning tunneling microscopy and transport measurements have been performed to investigate the electronic structure and its temperature dependence in heavily Sr and Na codoped PbTe, which is recognized as one of the most promising…

In the development of highly efficient photovoltaic cells, solid perovskite systems have demonstrated unprecedented promise, with the figure of merit exceeding nineteen percent of efficiency. In this paper, we investigate the optical and…

Materials Science · Physics 2015-02-05 Towfiq Ahmed , C. La-O-Vorakiat , T. Salim , Y. M. Lam , Elbert E. M. Chia , Jian-Xin Zhu

The substitution of bismuth by samarium in BiFeO3 is known to induce a structural phase transition from the polar phase to a non-polar phase, with a possible antiferroelectric intermediate structure. In this paper, we investigate the impact…

The structural and electronic properties of germanium clathrates Ge$_{46}$ and K$_8$Ge$_{46}$ are studied by first principles calculations within the local density approximation. The equilibrium structures are obtained by {\em ab initio}…

Condensed Matter · Physics 2009-10-31 Jijun Zhao , Alper Buldum , Jianping Lu , C. Y. Fong

We report on THz, infrared reflectivity and transmission experiments for wave numbers from 10 to 8000 cm$^{-1}$ ($\sim$ 1 meV - 1 eV) and for temperatures from 5 to 295 K on the Kitaev candidate material {\alpha}-RuCl$_3$. As reported…

Strongly Correlated Electrons · Physics 2017-10-18 S. Reschke , F. Mayr , Zhe Wang , Seung-Hwan Do , K. -Y. Choi , A. Loidl

In this study, we employ a first-principles approach to conduct a comprehensive investigation of the properties of nine common native point defects in cubic boron nitride. This analysis combines standard semi-local and dielectric hybrid…

Materials Science · Physics 2024-02-14 Ngoc Linh Nguyen , Hung The Dang , Tien Lam Pham , Thi Minh Hoa Nghiem

A strong coupling between electric polarization and elastic deformation in solids is an important factor in creating useful electromechanical nanodevices. Such coupling is typically allowed in insulating materials with inversion symmetry…

Materials Science · Physics 2024-10-30 Hidefumi Takahashi , Yusuke Kurosaka , Kenta Kimura , Akitoshi Nakano , Shintaro Ishiwata

The quasiparticle band structures of 3d transition metals, ferromagnetic Fe, Ni and paramagnetic Cu, are calculated by the GW approximation. The width of occupied 3d valence band, which is overestimated in the LSDA, is in good agreement…

Materials Science · Physics 2009-11-07 Atsushi Yamasaki , Takeo Fujiwara

A room-temperature infrared spectroscopy study of elemental tellurium at pressures up to 8.44 GPa in the energy range 0.015-2 eV is reported. Optical signatures of the high-pressure polymorphs are investigated and compared to the results of…

AlN thin films have been grown on Si (100) substrates by reactive ion beam sputter deposition (IBSD) at different substrate temperatures varying from room temperature (RT) to 500oC. Substrate temperature induced microstructural transition…

Materials Science · Physics 2016-02-23 Neha Sharma , Shilpam Sharma , K. Prabakar , S. Amirthapandian , S. Ilango , S. Dash , A. K. Tyagi

Organic electro-optic materials have demonstrated promising performance in developing electro-optic phase shifters. Their integration with other silicon photonic processes, nanofabrication complexities, and durability remains to be…

We report point contact measurements in high quality single crystals of Cu0.2Bi2Se3. We observe three different kinds of spectra: (1) Andreev-reflection spectra, from which we infer a superconducting gap size of 0.6mV; (2) spectra with a…

Superconductivity · Physics 2015-06-03 T. Kirzhner , E. Lahoud , K. B. Chaska , Z. Salman , A. Kanigel

We have performed a systematic high-momentum-resolution photoemission study on ZrTe$_5$ using $6$ eV photon energy. We have measured the band structure near the $\Gamma$ point, and quantified the gap between the conduction and valence band…

We present results from ab initio calculations of the mechanical properties of the rhombohedral phase (beta) of vanadium metal reported in recent experiments, and other predicted high-pressure phases (gamma and bcc), focusing on properties…

Materials Science · Physics 2009-11-13 B. Lee , R. E. Rudd , J. E. Klepeis , R. Becker