Harnessing Qudits

Can we bring applications for quantum technologies closer in reach?



Quantum computers leverage the laws of quantum mechanics to perform calculations beyond the capabilities of regular computers. There is however an important hurdle: quantum computers are hard to build, and current devices are therefore small and noisy. As a result, we need strategies to make near-future quantum computers more powerful, and hence useful.



A promising path towards making quantum computers more efficient and more robust to imperfections is the use of “qudits”: d-dimensional quantum systems that serve as computational units for quantum computations.



Regular computers are predominantly based on binary encodings, using 0s and 1s for information processing. Current quantum computers also mostly use binary encodings, albeit in quantum superpositions of the values 0 and 1 (qubits) that allow them to exploit the quantumness of these states and entanglement for information processing. Quantum systems underpinning today’s quantum computers can manipulate information in several different energy levels, i.e. in qudits.



Qudits allow for highly efficient quantum computations: Compared to 2-level approaches, qudit algorithms require smaller registers and require dramatically fewer gate operations.

So far, qudit-based quantum computing is still in its very beginnings. This talk explores the potential and first achievements of this approach.