Russell Bloomer

Parallel generation of quadripartite cluster entanglement in the optical frequency comb.

Scalability and coherence are two essential requirements for the experimental implementation of quantum information and quantum computing. Here, we report a breakthrough toward scalability: the simultaneous generation of a record 15 quadripartite entangled cluster states over 60 consecutive cavity modes (Q modes), in the optical frequency comb of a single optical parametric oscillator. The amount of observed entanglement was constant over the 60 Q modes, thereby proving the intrinsic scalability of this system. The number of observable Q modes was restricted by technical limitations, and we conservatively estimate the actual number of similar clusters to be at least 3 times larger. This result paves the way to the realization of large entangled states for scalable quantum information and quantum computing.

Experimental continuous-variable entanglement from a phase-difference-locked optical parametric oscillator

We observed continuous-variable entanglement between the bright beams emitted above threshold by an ultrastable optical parametric oscillator (OPO), classically phase locked at a frequency difference of

Entangling the optical frequency comb: Simultaneous generation of multiple 2 × 2 and 2 × 3 continuous-variable cluster states in a single optical parametric oscillator

161.827\phantom{\rule{0.2em}{0ex}}324\phantom{\rule{0.2em}{0ex}}0(5)\phantom{\rule{0.3em}{0ex}}\mathrm{MHz}

Broadband amplitude squeezing in a periodically poled KTiOPO4 waveguide.

. The amplitude-difference squeezing is

Toward quantum computing with oscillators

\ensuremath{-}3\phantom{\rule{0.3em}{0ex}}\mathrm{dB}

Protecting an EPR state by quantum engineering of decoherence

and the phase-sum one is

Playing the quantum harp: Multipartite squeezing and entanglement of harmonic oscillators

\ensuremath{-}1.35\phantom{\rule{0.3em}{0ex}}\mathrm{dB}

Nonlocal restoration of two-mode squeezing in the presence of strong optical loss

. Besides proving entanglement in a phase-locked OPO, such outstanding frequency-difference stability paves the way for transferring entanglement between different optical frequencies and densely implementing continuous-variable quantum information in the frequency domain.

Experimental continuous-variable entanglement of phase-locked bright optical beams

AbstractWe report on our research effort to generate large-scale multipartite optical-mode entanglement using as few physical resources as possible. We have previously shown that cluster-and GHZ-type N-partite continuous-variable entanglement can be obtained in an optical resonator that contains a suitably designed second-order nonlinear optical medium, pumped by at most