Showing papers by "Takao Aoki published in 2017"

Efficient Single-Photon Coupling from a Nitrogen-Vacancy Center Embedded in a Diamond Nanowire Utilizing an Optical Nanofiber.

Abstract: Nitrogen-Vacancy (NV) centers in diamond are promising solid-state quantum emitters that can be utilized for photonic quantum applications. Various diamond nanophotonic devices have been fabricated for efficient extraction of single photons emitted from NV centers to a single guided mode. However, for constructing scalable quantum networks, further efficient coupling of single photons to a guided mode of a single-mode fiber (SMF) is indispensable and a difficult challenge. Here, we propose a novel efficient hybrid system between an optical nanofiber and a cylindrical-structured diamond nanowire. The maximum coupling efficiency as high as 75% for the sum of both fiber ends is obtained by numerical simulations. The proposed hybrid system will provide a simple and efficient interface between solid-state quantum emitters and a SMF suitable for constructing scalable quantum networks.

Simple method for fabrication of diamond nanowires by inductively coupled plasma reactive ion etching

Abstract: Diamond nanowires are fabricated on a bulk, single crystalline diamond near an edge of aluminum coating using inductively coupled plasma reactive ion etching. Two different density areas are simultaneously appeared where the dense area has 9 times higher density than that of the sparse area while keeping the size of nanowires almost uniform in these areas. The nanowire sizes realized in the dense (sparse) area are 858 ± 22 nm (876 ± 25 nm) in height and 126 ± 6 nm (124 ± 7 nm) in diameter, which is suitable for applications in optical quantum information processing.