Laser heating effect on the power dependence of upconversion luminescence in Er3+-doped nanopowders

Raman spectra of the magnetic geometric frustration material – the botallackite-structure α-Cu2(OH)3Cl polycrystalline sample were measured down to liquid N2 temperature. It is found that the hydroxyl stretching bands shift abnormally according to the lattice thermal expansion effect of normal materials, i.e., they redshift with decreasing the sample temperature (negative thermal expansion) using liquid N2 cooling while other bands blueshift. This abnormality was also confirmed by observing the band-shifting caused by local laser heating effect using different laser powers, and can be qualitatively explained by checking the local hydroxyl environment with a trimeric hydrogen bond.

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The Upconversion Luminescence Properties of Er3+/Tm3+, Yb3+-Codoped Cubic BaLiF3

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2016.11870 ◽

2016 ◽

Vol 16 (4) ◽

pp. 3715-3719 ◽

Cited By ~ 1

Author(s):

Qinping Qiang ◽

Linna Guo ◽

Lili Han ◽

Yuhua Wang

Keyword(s):

Energy Levels ◽

Upconversion Luminescence ◽

Luminescence Properties ◽

Excitation Wavelength ◽

Power Dependence ◽

X Ray Diffraction ◽

X Ray ◽

Upconversion Emissions ◽

Surfactant Assisted ◽

Scanning Electron

Cubic BaLiF3 samples were prepared using a facile surfactant-assisted hydrothermal-microemulsion method. The samples were characterized by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The upconversion luminescence (UCL) properties of the Er3+/Tm3+, Yb3+-codoped BaLiF3 samples were measured under a 980 nm excitation wavelength. Moreover, the effects of varying the concentration of Li+ ions on the luminescence properties of Er3+, Yb3+ codoped BaLiF3 were also investigated. The Tm3+, Yb3+ codoped BaLiF3 samples displayed multicolor emissions. This behavior can be explained by the pump power dependence of the upconversion emissions and the energy levels diagram.

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Thermal effects on the Raman spectra of nanodiamonds

MRS Proceedings ◽

10.1557/opl.2011.309 ◽

2011 ◽

Vol 1282 ◽

Cited By ~ 1

Author(s):

Marc Chaigneau ◽

Hugues A. Girard ◽

Jean-Charles Arnault ◽

Razvigor Ossikovski

Keyword(s):

Raman Spectra ◽

Thermal Effects ◽

Laser Heating ◽

Quantum Confinement ◽

Laser Power ◽

Heating Effect ◽

Scattering Experiment ◽

Quantum Confinement Effects ◽

High Pressure High Temperature ◽

Peak Assignment

ABSTRACTWe report on the influence of the laser heating effect, potentially present in a Raman scattering experiment, on the behaviour of carbon phonon lines in the spectra of nanodiamond particles. Aside from the laser power used in the experiment, the extent of the thermal effect in question depends also on the nanodiamonds origin (obtained through detonation and high pressure high temperature techniques) as well as on the nanoparticles size. Laser heating should be properly taken into account when discussing Raman spectra of carbonaceous species, in particular, prior to addressing peak assignment and possible quantum confinement effects.

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