Parametric oscillation in nonlinear dipole arrays

An experimental investigation of large nonlinear dipole arrays is presented, using a diode-loaded dipole placed between two parallel conducting plates. Using this topology the authors were able to demonstrate enhanced conversion efficiency into the second harmonic and obtain spontaneous parametric oscillation for certain array geometries. Parametric oscillation was achieved by strongly driving the antenna at a single pump frequency and adjusting the cavity length for resonance at a subharmonic. A pump threshold for parametric down-conversion was observed, below which no sub-harmonics were produced. These results suggest using quasi-optical techniques for frequency multiplication and parametric up-conversion or amplification