Demonstration of optical short-term potentiation and short photonic memory. The analogy of PA phenomenon behavior to sound localization in avian nucleus laminaris (NL); a,b) 0.5 s lasting sound waves reach left (L) and right (R) ear with some phase delay depending on the source localization. b) The top of the phase-shifted sinusoidal waveforms reaching artificial NL, triggers (trig and pulse) photon excitation pulses (pulse width = 0.4 ms) to independently from laser diodes, which in a spatially colocalized manner stimulate optical PAS synapse by an effective pump intensity kinetic profiles (IP= (TL+TR)Io) and lead to appropriate (experimentally measured) PA kinetic emission intensity responses (IPA(t)), depending on the phase difference () between L and R ears; c,d) 2 pulse phase-difference (= 0-180)-dependent PA optical synapse integral luminescence intensity shows plasticity in response to (c) pulse width (= 0.1-50 ms,f= 10 Hz,IP= 103W cm-2) and d) sound frequency (= 10 ms,f= 10-40 Hz,IP= 103W cm-2), which enables to detect coincidence of two excitation pulses aiming to control the sensitivity and directionality of detection. The gray empty and solid rectangles denote experimental NL data for low mean input rate (MIR) 150 spikes s-1and strong MIR 400 spikes s-1sound wave intensities (data digitized from ref.[46]). The localization relative sensitivity is up to 0.61 for neurons and up to 3.2% deg-1for PAS (FigureS12, Supporting Information).
