Direct demonstration of sensitization at 980nm optical excitation in erbium-ytterbium silicates

Abstract

Sensitization of erbium by ytterbium in Er x Yb 2-x SiO 5 thin films at 980nm optical excitation is demonstrated by means of comparison of the 1.54µm photoluminescence intensities excited with 488nm and 980nm light. Additionally, it is shown that detrimental Er-Er interactions such as concentration quenching increase non-radiative decay rates at high erbium concentrations. Dilution of erbium by ytterbium reduces these interactions, leading to an increase of internal quantum efficiency.

On-chip light sources for silicon photonics

“…An effective strategy to address this issue is introducing ytterbium (Yb) and yttrium (Y) ions into the erbium silicates to dilute the erbium ions because they share a similar ionic radius (Y: 0.90 Å , Er: 0.88 Å , Yb: 0.86 Å ) and silicate crystal structure. Consequently, the CU and concentration quenching were suppressed, and the infrared PL efficiency was greatly enhanced by optimizing the composition of Yb and Y additions [43][44][45] . Optical amplification was comprehensively analyzed and measured in Er/Yb/Y silicate waveguides 46,47 , and a 30 dB cm 21 modal gain was demonstrated in a Si photonic crystal slot structure 47 .…”

Low threshold Er_xYb(Y)_2−xSiO_5 nanowire waveguide amplifier

“…Some groups [11][12][13][14] have obtained optimized ion concentrations for the Er/Yb/Y silicates. Based on the optimized materials, several kinds of Er/Yb/Y silicate waveguide structures have been fabricated for optical amplification purpose [15][16][17][18][19].…”

“…Therefore, characterizing and controlling Er ions distances in such Er silicates are necessary. To overcome this problem, Ytterbium (Yb) and Yttrium (Y) cations were added into the structure to dilute Er ions, which can substitute Er ions in the silicate lattice and prevent neighboring Er ions from causing upconversion [11][12][13][14].…”