Quantum tomography on high-dimensional systems

Project level: Honours

Quantum tomography---characterising a quantum system by assigning it a quantum state---is an essential building block for future technologies like quantum metrology or quantum computation. Ideal quantum tomography is accurate and robust to noise, while simultaneously being quick and efficient. The standard technique for decades only fulfills parts of these criteria and quickly becomes unfeasible, even for medium sized systems. As the number of possible states increases, the requirements on the number of measurements to characterise the system grow with it exponentially. The very feature that gives quantum mechanics its immense possibilities, hinders our capacity to describe it.  

In this project, you will explore efficient methods to find high-dimensional quantum states in theory and experiment. Going beyond the better-known qubit (2-dimensional), you will investigate qudits (d-dimensional) which offer a range of advantages like higher information capacity per particle or increased robustness to noise. Your experimental system will be single photons, where we encode the information in the transverse spatial mode/shape. In the lab, you will become familiar with essential techniques and equipment of quantum optics experiments. You will be integrated into our welcoming team environment and our position in the Centre of Excellence for Engineered Quantum Systems (EQUS) which offers great mentoring and networking opportunities.