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arXiv · 2010.00632

Robust and Efficient High-dimensional Quantum State Tomography

Markus Rambach·Mahdi Qaryan·Michael Kewming·Christopher Ferrie·Andrew G. White·Jacquiline Romero
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Abstract

The exponential growth in Hilbert space with increasing size of a quantum system means that accurately characterising the system becomes significantly harder with system dimension d. We show that self-guided tomography is a practical, efficient, and robust technique of measuring higher-dimensional quantum states. The achieved fidelities are over 99.9% for qutrits (d=3) and ququints (d=5), and 99.1% for quvigints (d=20), the highest values ever realised for qudits. We demonstrate robustness against experimental sources of noise, both statistical and environmental. The technique is applicable to any higher-dimensional system, from a collection of qubits through to individual qudits, and any physical realisation, be it photonic, superconducting, ionic, or spin.

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Markus Rambach, Mahdi Qaryan, Michael Kewming, Christopher Ferrie, Andrew G. White, Jacquiline Romero. 2020-10-01. Robust and Efficient High-dimensional Quantum State Tomography. https://doi.org/10.1103/physrevlett.126.100402

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