Faculty of Physics - University of Bucharest

UNIVERSITY OF BUCHAREST
FACULTY OF PHYSICS

Guest
2024-11-22 2:21

HOME CONFERENCES SEARCH LOGIN NEW USER IMAGES

Conference: Bucharest University Faculty of Physics 2015 Meeting

Section: Optics, Spectroscopy, Plasma and Lasers

Title:

Low and room temperature time-gated up-conversion emission of Er doped BiOCl excited at 1500 nm

Authors:

Ionut MATEI(1) , Daniel AVRAM(2) ,Carmen TISEANU(2)

Affiliation:

1)Faculty of Physics, University of Bucharest, Bucharest, Romania

2) National Institute for Laser, Plasma and Radiation Physics, Bucharest 077125, Romania

E-mail

m.ionut_catalin@yahoo.com

Keywords:

time-gated resolved up-conversion,NIR,ESA/GSA,ETU,CIE

Abstract:

Herein, we present our results on the up - conversion mechanisms and properties of Er doped Bismuth Oxy-Chloride (Er - BiOCl) under down- (Ultraviolet, UV to Visible, Vis spectral range) and up-conversion (Near Infrared, NIR) excitation. In recent years, BiOCl has drawn considerable attention for industrial applications, due to its unique electronic, photonic and catalytic performance. Despite the outstanding properties of the BiOCl, such as low phonon energy, high density, low toxicity, facile doping with lanthanide ions (due to size and charge compatibility between Bi3+ and Ln3+ ions) [1], few investigations have been dedicated to lanthanide ions doped BiOCl materials as possible candidates for optical imaging applications. We analyze the dependencies of red (~670 nm), and NIR (~800 nm) to green (~543 nm) emission ratio with Er concentrations (1 and 5%), excitation mode (380, 490 and ~1500 nm) and delay after the laser pulse. The up - conversion excitation spectra and decays are all analyzed in respect with the interplay between Ground State Absorption/Excited State Absorption and Energy Transfer Up-conversion mechanisms [2, 3]. Also, the number of photons necessary to populate the red, green and NIR emission levels are estimated from the dependency of intensity of the up-conversion emission vs. energy of the laser excitation pulse [4]. The CIE (International Commission on Illumination) diagram shows a single excitation delay tunable emission that change color from yellowish green to reddish orange by increasing the delay from 0.001 to 1 ms.

References:

1 Y. Li, Z. Song, C. Li, R. Wan, J. Qiu, Z. Yang, Z. Yin, Y. Yang, X. Wang, and Q. Wang, “Efficient near-infrared to visible and ultraviolet upconversion in polycrystalline BiOCl:Er3+/Yb3+ synthesized at low temperature,” Ceram. Int. 39(8), 8911–8916 (2013).

2 D. Avram, B. Cojocaru, M. Florea, V. Teodorescu, I. Tiseanu and C. Tiseanu "NIR to Vis - NIR up - conversion and X-ray excited emission of Er doped high Z BiOCl." Optical Materials Express, 5(5), 951-962 (2015)

3 Francois Auzel “Upconversion and Anti-Stokes Processes with f and d Ions in Solids” Chem. Rev., 104 (1), 139-174 (2004)

4 M. Pollnau, D. R. Gamelin, S. R. Luthi and H. U. Gudel "Power dependence of upconversion luminescence in lanthanide and transition-metal-ion systems." Physical Review B 61(5), 3337 (2000)