title: Strain-optic active control for quantum integrated photonics.
abstract: We present a practical method for active phase control on a photonic chip that has immediate applications in quantum photonics. Our approach uses strain-optic modification of the refractive index of individual waveguides, effected by a millimeter-scale mechanical actuator. The resulting phase change of propagating optical fields is rapid and polarization-dependent, enabling quantum applications that require active control and polarization encoding. We demonstrate strain-optic control of non-classical states of light in silica, showing the generation of 2-photon polarisation N00N states by manipulating Hong-Ou-Mandel interference. We also demonstrate switching times of a few microseconds, which are sufficient for silica-based feed-forward control of photonic quantum states.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Humphreys
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Metcalf
authors.forename: Justin B
authors.initials: JB
authors.lastname: Spring
authors.forename: Merritt
authors.initials: M
authors.lastname: Moore
authors.forename: Patrick S
authors.initials: PS
authors.lastname: Salter
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Booth
authors.forename: W
authors.initials: W
authors.lastname: Steven Kolthammer
authors.forename: Ian A
authors.initials: IA
authors.lastname: Walmsley