title: Creation and measurement of broadband squeezed vacuum from a ring optical parametric oscillator.
abstract: We report a 65 MHz-bandwidth triangular-shaped optical parametric oscillator (OPO) for squeezed vacuum generation at 860 nm. The triangle structure of our OPO enables the round-trip length to reach 45 mm as a ring cavity, which provides a counter circulating optical path available for introducing a probe beam or generating another squeezed vacuum. Hence our OPO is suitable for the applications in high-speed quantum information processing where two or more squeezed vacua form a complicated interferometer, like continuous-variable quantum teleportation. With a homemade, broadband and low-loss homodyne detector, a direct measurement shows 8.4 dB of squeezing at 3 MHz and also 2.4 dB of squeezing at 100 MHz.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Serikawa
authors.forename: Jun-Ichi
authors.initials: JI
authors.lastname: Yoshikawa
authors.forename: Kenzo
authors.initials: K
authors.lastname: Makino
authors.forename: Akira
authors.initials: A
authors.lastname: Frusawa