Applied Physics Letters
Single-photon emission at 1.5 μ m from an InAs/InP quantum dot with highly suppressed multi-photon emission probabilities
Tomoyuki MIYAZAWA, K. Takemoto, Y. Nambu, Shigehito Miki, Taro Yamashita, Hirotaka Terai, Mikio Fujiwara, Masahide Sasaki, Yoshiki Sakuma, Motomu Takatsu, Tsuyoshi Yamamoto, Yasuhiko Arakawa
Abstract
We have demonstrated highly pure single-photon emissions from an InAs/InP quantum dot at the wavelength of 1.5 μm. By applying quasi-resonant excitation, one exciton is deterministically generated in an excited state, which then relaxes to the exciton ground state before recombining to emit a single photon. The photon-correlation function of the emission from the exciton ground state exhibits a record g(2)(0) value of (4.4 ± 0.2) × 10−4 measured using high-performance super-conducting single-photon detectors, without any background subtraction. This single-photon source with extremely low multi-photon emission probability paves the way to realize long distance quantum key distribution and low error-rate quantum computation.