Superconducting single-photon camera for quantum state tomography

• Main Authors: Brosseau, Pierre, Vetlugin, Anton N., Adamo, Giorgio, Dong, Shuyu, Soci, Cesare
• Other Authors: Interdisciplinary Graduate School (IGS)
• Format: Conference or Workshop Item
• Language: English
• Published: 2024
• Subjects: Physics; Quantum state tomography; Superconducting nanowire single-photon detectors (SNSPD); Metamaterials; Optical quantum technologies; Multi-pixel camera
• Online Access: https://hdl.handle.net/10356/177984; https://www.optica.org/events/topical_meetings/quantum/
• Institution: Nanyang Technological University

The polarization of quantum light provides a versatile and robust platform for implementing optical quantum technologies. Polarization quantum states are widely used in fundamental tests of quantum mechanics, quantum key distribution and entanglement swapping, quantum metrology and quantum computing. However, the practical utility of such states is defined by the ability to characterize them quickly and reliably. Quantum state tomography, a set of polarization measurements that recovers the density matrix of an unknown state, is routinely performed using bulky optical components and single-photon detectors, as shown in Fig. 1(a). Since active rotation of optical components (e.g., wave plates) is usually required to perform measurements in different polarization bases, this approach has limited scalability and robustness.