Unidirectional Emission of a Site-Controlled Single Quantum Dot from a Pyramidal Structure.
Emission control of a quantum emitter made of semiconductor materials is of significance in various optical applications. Specifically, the realization of efficient quantum emitters is important because typical semiconductor quantum dots are associated with low extraction efficiency levels due to their high refractive index contrast. Here, we report bright and unidirectional emission from a site-controlled InGaN quantum dot formed on the apex of a silver-coated GaN nanopyramidal structure. We show that the majority of the extracted light from the quantum dot is guided toward the bottom of the pyramid with high directionality. We also demonstrate that nanopyramid structures can be detached from a substrate, thus demonstrating great potential of this structure in various applications. To clarify the directional radiation, the far-field radiation pattern is measured using Fourier microscopy. This scheme will pave the way toward the realization of a bright and unidirectional quantum emitter along with easy fabrication and large-area reproducibility.
Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology , 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
Sejeong
S
Kim
Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology , 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
Su-Hyun
SH
Gong
Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology , 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
Jong-Hoi
JH
Cho
Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology , 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
Yong-Hoon
YH
Cho
Unidirectional emission; efficient single emitter; self-aligned coupling; single-quantum emitter