Post-selected von Neumann Measurement with Superpositions of Orbital-Angular-Momentum Pointer States

TL;DR

This paper explores how orbital angular momentum pointers in von Neumann measurements can be optimized through superpositions of Gaussian and Laguerre-Gaussian states, leading to non-Gaussian states with improved quantum measurement properties.

Contribution

It introduces the use of OAM pointers with superpositions of Gaussian and LG states in von Neumann measurements, demonstrating state transformation and performance enhancement.

Findings

Optimized superpositions improve measurement precision.

Postselection induces Gaussian to non-Gaussian state transition.

Enhanced signal-to-noise ratio and quantum state properties.

Abstract

We investigated an orbital angular momentum (OAM) pointer within the framework of von Neumann measurements and discovered its significant impact on optimizing superpositions of Gaussian and Laguerre-Gaussian (LG) states. Calculations of the quadrature squeezing, the second-order cross-correlation function, the Wigner function, and the signal-to-noise ratio (SNR) support our findings. Specifically, by carefully selecting the anomalous weak value and the coupling strength between the measured system and the pointer, we demonstrated that the initial Gaussian state transforms into a non-Gaussian state after postselection. This transition highlights the potential of OAM pointers in enhancing the performance of quantum systems by tailoring state properties for specific applications.