Creation of a high-resolution atomic frequency comb and optimization of the pulse sequence for high-efficiency quantum memory in 167Er:Y2SiO5

Abstract

We created high-resolution atomic frequency combs (AFCs) and optimized the pulse sequence used in AFC memory to realize highly efficient AFC quantum memory using the 167Er3+:Y2SiO5 hyperfine level system. As a result, the formation and relaxation times of AFCs were revealed, and AFCs with a resolution of 800 kHz were created by using an appropriate pump light intensity. An efficiency of 0.16% with a memory time of 0.5 µs was achieved even under a zero magnetic field and a 10 ppm Er concentration sample. This result paves the way for realizing highly efficient communication-wavelength AFC quantum memory.