Abstract: Provided herein are Ising logic-gates having at least four POs, each coupled to at least one other of the POs and configured to passively activate, responsive to a pump signal, a parametric oscillation, an output signal of the PO switchable between in-phase and out-of-phase, a plurality of coupling elements, each for coupling two of the at least four POs to form a plurality of blocks, each block having a mode corresponding to or interactive with a logical input, the mode passively activatable via the coupled POs to produce a corresponding block output, the plurality of block outputs tuned to selectively frustrate the plurality of block outputs to produce an output at negligible amplitude or constructively interfere with the plurality of block outputs to produce the output at detectable amplitude; and a power combiner for power-combining the plurality of block outputs to produce the output.

Abstract: Provided herein are systems for a wireless, battery-free acoustic sensor having a subharmonic tag (SubHT) and an acoustic transducer, wherein the acoustic transducer is integrated with the SubHT, such that an acoustic signal received by the acoustic transducer modulates an electrical output of the SubHT when the SubHT is interrogated by a radiofrequency input signal of a reader device, resulting in conversion of the acoustic signal into information transmitted by the sensor via a radiofrequency output signal without the use of battery power.