Abstract: Optical quantum memories can be used for storage or generation and subsequent retrieval of quantum light for the purpose of long-distance quantum communication. However, it is beneficial to consider more functions of quantum memories, which may then become parts of more complex hybrid quantum networks. In my works I have demonstrated protocols for spin-wave processing based on interference in multiplexed optical quantum memories [1,2]. In particular, our schemes based on ac-Stark modulation allow for reprocessing of light in both spatial and spectro-temporal degrees of freedom, enabling for example interference of pulses entering the memory at different times [3], or more complex manipulation such as a time-frequency fractional Fourier transform [4]. I will also discuss prospects for introducing Rydberg atoms to the scheme in order to facilitate multi-photon interaction or memory-enabled microwave-to-optical transduction via multimode nonlinear quantum optics.
[1] M. Parniak et al., Nature Communications 8, 2140 (2017)
[2] M. Parniak et al., Phys. Rev. Lett. 122, 063604 (2019)
[3] M. Mazelanik et al., Nature Communications 13, 691 (2022)
[4] B. Niewelt et al., Phys. Rev. Lett. 130, 240801 (2023)