Quantum Measurements

Abstract This work demonstrates the capabilities of an entangled photon-pair source at telecom wavelengths, based on a photonic integrated Si3N4 microresonator with monolithically integrated piezoelectric frequency tuning. Previously, frequency tuning of photon pairs generated by microresonators has only been demonstrated using thermal control, however these have limited actuation bandwidth and are not compatible with cryogenic environments.

Abstract Silicon nitride (Si3N4) is commonly employed to integrate third-order nonlinear optical processes on a chip. Its amorphous state, however, inhibits significant second-order nonlinear response. Recently, second-harmonic generation enhancement has been observed in Si3N4 waveguides after an all-optical poling (AOP) method.

Multi-mode fields In a similar manner, for a multi-mode field composed of a few sinusoidal terms and by adding resonant inductive terms as \(\frac{1}{2}\Sigma {L_n}{\dot{{\hat{q}}}}_n^2\) with \({{\hat{q}}_n} = S{{\hat{Q}}_n}\) and \({\omega _n} = 1/\sqrt {S{L_n}{C_0}}\), we may write down the total Hamiltonian $${\hat{H}} = \hbar \mathop {\sum}\limits_n {\omega _n}\left( {{\hat{a}}_n^\dag {{{\hat{a}}}_n} + \frac{1}{2}} \right) - \frac{{\hbar \tau }}{4}{\left[ {\mathop {\sum}\limits_n \sqrt...