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Results for “Te-Tm”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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8 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Dynamics of Spin Polarization in Tilted Polariton Rings

We have observed the effect of pseudomagnetic field originating from the polaritonic analog of spin-orbit coupling [transverse electric and transverse magnetic (TE-TM) splitting] on a polariton condensate in a ring-shaped microcavity. The effect gives rise to a stable four-leaf pattern around the ring as seen from the linear polarization measurements of the condensate photoluminescence. This pattern is found to originate from the interplay of the cavity potential, energy relaxation, and TE-TM splitting in the ring. Our observations are compared to the dissipative one-dimensional spinor Gross-Pitaevskii equation with the TE-TM splitting energy, which shows good qualitative agreement.

CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS↗
DOE OSTI2024

Integrated polarization-free Bragg filters with subwavelength gratings for photonic sensing

We present polarization-free Bragg filters having subwavelength gratings (SWGs) in the lateral cladding region. This Bragg design expands modal fields toward upper cladding, resulting in enhanced light interaction with sensing analytes. Two device configurations are proposed and examined, one with index-matched coupling between transverse electric (TE) and transverse magnetic (TM) modes and the other one with hybrid-mode (HM) coupling. Both configurations introduce a strong coupling between two orthogonal modes (either TE-TM or HM 1 -HM 2 ) and rotate the polarization of the input wave through Bragg reflection. The arrangements of SWGs help to achieve two configurations with different orthogonal modes, while expanding modal profiles toward the upper cladding region. Our proposed SWG-assisted Bragg gratings with polarization independency eliminate the need for a polarization controller and effectively tailor the modal properties, enhancing the potential of integrated photonic sensing applications.

Optics↗
NASA NTRS1982

Development of a tantalum pentoxide Luneberg lens

A process has been developed for the fabrication of a tantalum pentoxide waveguide Luneburg lens as the input collimator for an optical signal processing circuit on a silicon substrate, such as an integrated wavelength demultiplexer. The development of such a lens involved improvement of the deposition mask profile, reduction of surface scattering by underlaying the lens, reduction of edge scattering by using shims under the mask, and prediction and measurement of the TE-TM polarization aberration. It is shown that polarization aberration significantly affects the design of a demultiplexer system.

Bryan, D. A.↗
DOE OSTI2020

Materials Data on TmTe by Materials Project

TmTe is Molybdenum Carbide MAX Phase-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Tm is bonded to six equivalent Te atoms to form a mixture of distorted edge and corner-sharing TmTe6 pentagonal pyramids. All Tm–Te bond lengths are 3.07 Å. Te is bonded to six equivalent Tm atoms to form a mixture of edge, face, and corner-sharing TeTm6 octahedra. The corner-sharing octahedral tilt angles are 45°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TmTe by Materials Project

TmTe is Halite, Rock Salt structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Tm is bonded to six equivalent Te atoms to form a mixture of edge and corner-sharing TmTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Tm–Te bond lengths are 3.04 Å. Te is bonded to six equivalent Tm atoms to form a mixture of edge and corner-sharing TeTm6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TmTe by Materials Project

TmTe is Tetraauricupride structured and crystallizes in the tetragonal P4mm space group. The structure is three-dimensional. Tm is bonded in a body-centered cubic geometry to eight equivalent Te atoms. There are four shorter (3.24 Å) and four longer (3.25 Å) Tm–Te bond lengths. Te is bonded in a body-centered cubic geometry to eight equivalent Tm atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TmTe3 by Materials Project

TmTe3 crystallizes in the orthorhombic Cmcm space group. The structure is two-dimensional and consists of two TmTe3 sheets oriented in the (0, 1, 0) direction. Tm3+ is bonded in a 7-coordinate geometry to seven Te1- atoms. There are a spread of Tm–Te bond distances ranging from 3.05–3.44 Å. There are three inequivalent Te1- sites. In the first Te1- site, Te1- is bonded in a 4-coordinate geometry to six equivalent Tm3+ atoms. In the second Te1- site, Te1- is bonded in a distorted single-bond geometry to one Tm3+ and four equivalent Te1- atoms. All Te–Te bond lengths are 3.11 Å. In the third Te1- site, Te1- is bonded in a 4-coordinate geometry to four equivalent Te1- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tm2Te3 by Materials Project

Tm2Te3 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. there are two inequivalent Tm3+ sites. In the first Tm3+ site, Tm3+ is bonded to six Te2- atoms to form a mixture of corner and edge-sharing TmTe6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are a spread of Tm–Te bond distances ranging from 3.05–3.08 Å. In the second Tm3+ site, Tm3+ is bonded to six Te2- atoms to form a mixture of corner and edge-sharing TmTe6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are a spread of Tm–Te bond distances ranging from 3.04–3.06 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a rectangular see-saw-like geometry to four Tm3+ atoms. In the second Te2- site, Te2- is bonded in a rectangular see-saw-like geometry to four Tm3+ atoms.

36 MATERIALS SCIENCE↗