Graphene acousticelectric latch

We implement a logic latch by using a graphene-based acousticelectric transducer. We operate two pairs of inter-digital transducers to launch surface acoustic waves (SAWs) on a piezoelectric LiNbO₃ substrate and exploit graphene, an intrinsic two-dimensional gas, as channel material to sustain acousticelectric current I_ae induced by SAWs. By corporately tuning the amplitude of two SAWs, we can manipulate the propagation direction of I_ae so the magnitude and the sign of I_ae can be manipulated. We define the I_ae zero crossing as I_ae^off, and then demonstrate that I_ae can be switched with a ratio I_ae^on / I_ae^off ~ 10⁴ at a rate up to few tens kHz. Our device with the newly-developed sensing scheme provides a means to convert incoming acoustic waves modulated by digitized data sequence onto electric signals with frequency band suitable for digital audio modulation. Consequently, it can perform an effective latch operating and, potentially, may open a route for the future development of various logic devices based on two-dimensional materials.