In order to design a quantum computer, one has to understand the physics of how it operates. This project will develop a simulation of the Ising machine quantum computer, in a joint project with NTT Research, one of the largest international industrial research laboratories.
The Ising machine is a novel type of large-scale quantum computer, which solves NP-hard problems with large potential impact in many practical applications. The class of problems that are solved are the MAX-CUT graph minimization problems commonly found in optimization and routing. Unlike most existing quantum computing research programs, these problems are of widespread direct relevance to many fields. Such difficult optimization challenges are a long-spread limitation for conventional computers, owing to their exponential complexity.
However, the PhD is not limited to these problems, which are already of wide applicability to routing and VLSI design. There are many other related NP-hard optimization problems which may be tractable with the novel quantum Ising machine hardware.
The Ising machine is a non-equilibrium, coherently driven physical system composed of linked parametric amplifiers, whose steady-state is thought to be equivalent to the ground state of the Ising model with variable coupling, which is known to solve MAX-CUT problems. Simulations of Ising machine operation will be carried out in a joint program with the new NTT Research Phi laboratory in San Jose. Theoretical work will be carried out in conjunction with the ongoing quantum computing experiments at NTT Labs, Stanford, Cornell and Caltech.
As well as utilizing existing phase-space representations and software, the student will develop new GPU based software to parallelize and speed up results. This will include novel algorithms as well, which will make use of Q-functions and extra-dimensional equilibration. An important task will be to develop and apply novel entanglement and Schrodinger cat formation measures, in order to estimate quantum entanglement and non-classicality during the optimization process.
This project will be to work with a team to optimize hardware protocols. This will require developing code to simulate the quantum computer, either using phase-space methods based on stochastic equations or using more advanced algorithms for stochastic bridges. The target hardware will include both the fiber-optical hardware currently in NTT and Stanford, and a new generation of superconducting quantum circuit experiments. This will involve group meetings, by video and in person, with Phi network researchers in USA and Japan.
Funding will be either directly through the research grant, or via a jointly funded program with Swinburne University funding.