Differential operation is an integral component of wave-based computation and has been extensively employed in signal processing applications. Nevertheless, current acoustic differentiators are essentially restricted to functioning independently in the temporal or spatial domains. Here, we propose an acoustic spatiotemporal differentiator (ASTD) utilizing an acoustic metagrating (AMG) that simultaneously performs first-order differentiation and generates a spatiotemporal vortex (STV). By breaking spatial mirror symmetry, the ASTD possesses a transfer function exhibiting linear dependence on both spatial wave-vector and temporal frequency, thereby enabling the first-order differentiation. A theoretical analysis reveals that, when introducing a π/2 phase delay between spatial and temporal differentiations, the ASTD can produce an STV with a topological charge (TC) opposite to that of the vortex in the momentum-frequency domain. Both simulations and experiments confirm the differentiation capability and STV generation of the ASTD. It is further demonstrated that the differentiator can detect sharp changes in spatiotemporal pulses even with intricate profiles. These findings offer a promising platform for advancing acoustic computing and signal processing in the spatiotemporal domain.

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• Acoustic vortices
• Analog computation
• Physics of computation
• Topological effects in acoustic systems
• Acoustic metamaterials
• Devices
• Metagratings
• Acoustic techniques