Fig. 1
Basic principle and setup of the photonic–phononic memory. a Storing process: an optical data pulse is depleted by a strong counter-propagating write pulse, storing the data pulse as an acoustic phonon. b Retrieval process: in the retrieval process a read pulse depletes the acoustic wave, converting the data pulse back into the optical domain. c A basic schematic of the experimental setup. The inset shows a chalcogenide chip next to a 50-cent coin. The chip contains more than 100 spiral waveguides with different lengths (8.6, 11.7 and 23.7 cm). Note: this is only a schematic and the actual setup is more advanced and can be found in Supplementary Fig. 1 (CW continuous wave, SSB single-sideband modulator, IM intensity modulator, PG pulse generator, BP bandpass filter, PD photo-detector, LO local oscillator, Ω Brillouin frequency shift)
