Feb 26 2024Reviewed by Lexie Corner
A novel technique has been employed by Paderborn University scientists to ascertain the properties of optical, or light-based, quantum states.
They are employing so-called homodyne detection for the first time with specific photon detectors, gadgets that can identify individual light particles. The approach is crucial for quantum information processing because it can characterize optical quantum states. Accurate comprehension of the attributes is crucial for application in quantum computing, among other applications. The findings were published in the specialized journal Optica Quantum.
Homodyne detection is a method frequently used in quantum optics to investigate the wave-like nature of optical quantum states.
Timon Schapeler, Department of Physics, Paderborn University
Utilizing the technique, Schapeler and Dr. Maximilian Protte have looked into the so-called continuous variables of optical quantum states. The varying characteristics of light waves are involved in this. These include, among other things, the amplitude or phase or the oscillatory behavior of waves, which are crucial for the focused manipulation of light.
Superconducting nanowire single-photon detectors, which are currently the fastest devices for photon counting, were used for the first time in the measurements by physicists. With their unique experimental setup, the two scientists have demonstrated a linear response of a homodyne detector with superconducting single-photon detectors to the input photon flux. This indicates that the measured signal is proportionate to the input signal, to put it another way.
In principle, the integration of superconducting single-photon detectors brings many advantages in the area of continuous variables, not least the intrinsic phase stability. These systems also have almost 100 % on-chip detection efficiency. This means that no particles are lost during detection. Our results could enable the development of highly efficient homodyne detectors with single-photon sensitive detectors.
Timon Schapeler, Department of Physics, Paderborn University
Beyond qubits, the standard computing units of quantum computers, working with continuous variables of light opens up new and exciting possibilities in quantum information processing.
Journal Reference:
Protte, M., et al. (2024) Low-noise balanced homodyne detection with superconducting nanowire single-photon detectors. Optica Quantum. doi.org/10.1364/OPTICAQ.502201
Source: https://www.uni-paderborn.de/