arXiv subjects

Arman Mansouri

Publications and source records attributed to Arman Mansouri.

3 recordsLinked to original sources

arXiv2026

Experimental demonstration of a multi-particle collective measurement for optimal quantum state estimation

We experimentally demonstrate a two-particle collective measurement proposed as the optimal solution to a quantum state estimation game. Our results suggest that, in practice, the collective measurement strategy is at least as good as the best local approach, and it achieves a higher average fidelity when accounting for systematic errors. This photonic implementation uses a recently developed universal two-photon projective measurement based on Hong-Ou-Mandel interference, polarization-dependent loss, and unitary operations. We compare the performance to the case where the entangling component of the measurement is suppressed. We further apply the collective measurement to quantum state tomography, observing a near-optimal scaling of the infidelity with the total number of samples.

quant-ph↗

arXiv2025

Fast and Automated Optical Polarization Compensation of Fiber Unitaries

The polarization of light is critical in various applications, including quantum communication, where the photon polarization encoding a qubit can undergo uncontrolled changes when transmitted through optical fibers. Bends in the fiber, internal and external stresses, and environmental factors cause these polarization changes, which lead to errors and therein limit the range of quantum communication. To prevent this, we present a fast and automated method for polarization compensation using liquid crystals. This approach combines polarimetry based on a rotating quarter-waveplate with high-speed control of the liquid-crystal cell, offering high-fidelity compensation suitable for diverse applications. Our method directly solves for compensation parameters, avoiding reliance on stochastic approaches or cryptographic metrics. Experimental results demonstrate that our method achieves over 99% fidelity within an average of fewer than six iterations, with further fine-tuning to reach above 99.5% fidelity, providing a robust solution for maintaining precise polarization states in optical systems.

quant-ph↗

arXiv2024

Boson Sampling with Gaussian input states: toward efficient scaling and certification

A universal quantum computer of large scale is not available yet, however, intermediate models of quantum computation would still permit demonstrations of a quantum computational advantage over classical computing and could challenge the Extended Church-Turing Thesis. One of these models based on single photons interacting via linear optics is called Boson Sampling. Although Boson Sampling was demonstrated and the threshold to claim quantum computational advantage was achieved, the question of how to scale up Boson Sampling experiments remains. To make progress with this problem, here we present a practically achievable pathway to scale Boson Sampling experiments by combining continuous-variable quantum information and temporal encoding. We propose the combination of switchable dual-homodyne and single-photon detections, the temporal loop technique, and scattershot-based Boson Sampling. We detail the required assumptions for concluding computational hardness for this configuration. Furthermore, this particular combination of techniques moves towards an efficient scaling and certification of Boson Sampling, all in a single experimental setup.

quant-ph↗