Hybrid Photonic Qubits

CQC2T research at UNSW@ADFA will contribute to the Quantum Resources, Quantum Communications and Photonic Quantum Computation work packages.

Photonic Quantum Computation: Non-deterministic gate operation is a significant challenge to the development of larger-scale photonic quantum computation circuits. Compared to other optical schemes, coherent-state quantum computing (CSQC) has a number of desirable features, including more efficient basic gates, efficient "Bell-state" measurement, deterministic teleportation and "cheap" error correction protocols. The principle goal of the Hybrid Photonic Qubits Program is to demonstrate efficient (P>0.5) entangling gates. Heralded photon-subtracted squeezed states will be used as the nonclassical resource in CSQC. One-way computation is another potentially high-payoff approach to larger-scale photonic quantum computation circuits. The Hybrid Photonic Qubits program will contribute to the Centre in this area also.

Quantum Communications: The capacity of a quantum communication channel will be a significant issue for full-scale quantum communications. The Hybrid Photonic Qubits program will demonstrate multiplexed quantum communication protocols, such as teleportation of non-classical continuous-variable states and CSQC basis states, on a multiplexed quantum bus.

Quantum Resources: The generation of non-classical resource states and the development of new techniques of quantum measurement and control are also critical issues. The Hybrid Photonic Qubits program will continue to work in the area of adaptive phase estimation. Members of the Centre have made the first experimental demonstration of adaptive quantum smoothing, breaking the standard quantum limit for optical phase estimation by more than a factor of 2 and considerably improving on the previous world record. The technique will be used in the preparation and manipulation of a variety of non-classical resource states useful for quantum communications and quantum computation. The team will also work to deliver next-generation detectors at a telecommunications wavelength.