Broadband near infrared quantum cutting in Bi–Yb codoped Y2O3 transparent films on crystalline silicon

By a pulsed laser deposition technique the efficient broadband near-infrared downconversion Bi–Yb codoped crystallization Y2O3 transparent films have been grown successfully on Si (1 0 0) substrates. Upon excitation of ultraviolet photon varying from 300 to 400 nm, the near infrared quantum cutting has been obtained, which is originated from the transitions of the transition-metal Bi3+ 3P1 level to Yb3+ 2F5/2 level. The downconversion quantum efficiency of films is estimated to be 152%. The transparent Y2O3 films may have potential application in enhancing the conversion efficiency of crystalline Si solar cells.