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 Ising machines having a resonant input mesh driven by a pump signal, a resonant output mesh coupled to the input mesh through a nonlinear component to form a parametric frequency divider (PFD), and the nonlinear component configured to passively activate, responsive to the pump signal exceeding a threshold power, a parametric oscillation between the input and output meshes having an oscillation frequency equal to half an angular input frequency of the pump signal, wherein an output signal of the PFD can be switched between an in-phase state and an out-of-phase state.

Abstract: Provided herein are methods and systems for subharmonic tags including a single antenna having a reactive input impedance and a set of lumped components coupled to the antenna, the lumped components having a frequency-dependent input impedance, wherein the frequency-dependent input impedance of the lumped components causes the coupled antenna and lumped components to resonate at both an input frequency of the subharmonic tag and at an output frequency of the subharmonic tag.

Abstract: Provided herein are Ising tags for multidimensional threshold sensing including at least three parametric oscillators (POs), each coupled to and power-combined with at least one other of the at least three POs, each of the at least three POs configured to passively activate, responsive to a pump signal exceeding a threshold power, wherein an output signal of the PO can be switched between in-phase and out-of-phase, sensor elements each for sensing one of a plurality of PoIs, each coupling two of the POs and configured to set the threshold power of the coupled POs to be exceeded by the pump signal upon violation of a corresponding parameter of interest threshold, wherein a multidimensional sensing threshold is defined as a locus of all combinations of values of the parameters of interest for which the output signals of the POs constructively interfere to increase an output power of the combined output signal.

Abstract: Provided herein are Ising machines having a resonant input mesh driven by a pump signal, a resonant output mesh coupled to the input mesh through a nonlinear component to form a parametric frequency divider (PFD), and the nonlinear component configured to passively activate, responsive to the pump signal exceeding a threshold power, a parametric oscillation between the input and output meshes having an oscillation frequency equal to half an angular input frequency of the pump signal, wherein an output signal of the PFD can be switched between an in-phase state and an out-of-phase state.