Over a year in the making, the mega paper about continuous variable cluster states has finally been published on the archives. Titled, `Quantum Computing with Continous Variable Clusters‘, the paper is essentially a refinement of the idea I jointly proposed as a first year PhD student that it would be pretty cool to have an formulation of measurement based computation where each node was a quantum harmonic oscillator.

Though the idea seemed fairly second nature at the time (hey, just take qubits and replace them with optical modes!), the level of interest in it has been quite a pleasant surprise. The second follow-up paper aims at polishing the idea, and includes a lot of the details that was sort of brushed away during the initial proposal.

Quantum Computing with Continuous-Variable Clusters
Mile Gu, Christian Weedbrook, Nicolas C. Menicucci, Timothy C. Ralph, Peter van Loock

Continuous-variable cluster states offer a potentially promising method of implementing a quantum computer. This paper extends and further refines theoretical foundations and protocols for experimental implementation. We give a cluster-state implementation of the cubic phase gate through photon detection, which, together with homodyne detection, facilitates universal quantum computation. In addition, we characterize the offline squeezed resources required to generate an arbitrary graph state through passive linear optics. Most significantly, we prove that there are universal states for which the offline squeezing per mode does not increase with the size of the cluster. Simple representations of continuous-variable graph states are introduced to analyze graph state transformations under measurement and the existence of universal continuous-variable resource states.

Arxiv Link

Not the most exciting paper, but it has pretty pictures, including my first ever attenmpt at doing rendering wtih 3D studio max. That’s got to be worth something right? Also, I must thank Christian Weedbrook, who capacity in eliminating all of my typos as I busily hammered away at furniture here in Singapore is so remarkable that I’m convinced he secretly hides a quantum computer in his back yard!