[13a-A35-1~10] 13.9 Optical properties and light-emitting devices

[13a-A35-8] Broadband-sensitive upconverters for crystalline silicon solar cells (II)

〇Yasuhiko Takeda¹, Mizuno Shintaro¹, Luitel Hom Nath¹, Yamanaka Ken-ichi¹, Tani Toshihiko¹ (1.Toyota Central L&D Labs.)

Keywords:upconversion, energy transfer, crystalline silicon solar cell

We investigated the mechanism of Ni²⁺-sensitized Er³⁺ upconversion emission of a broadband-sensitive upconverter La(Ga_0.5Sc_0.5)O₃:Er,Ni,Nb, which upconverts 1.1-1.6 um photons to 0.98 um photons, by time-resolved spectroscopy. The dominant mechanism is excitation of two Er³⁺ emitters to ⁴I_13/2 caused by energy transfer from two excited Ni²⁺ sensitizers followed by energy exchange between them leading to further excitation to ⁴I_9/2.