Neutron Interferometry:

Intro

This repository contains some projects on neutron interferometry. Neutron interferometry is interferometry with neutrons. Interferometry, in most cases, involves the coherence splitting of a wave and its interferences with another operation. In neutrons, the interferometer is fabricated from single crystals. The most common geometry is the three-blade geometry shown below. There are other geometries, including the four and five-blade neutron interferometers. A review of interferometry including these geometries can be found in the article Neutron interferometry at the NIST. Interferometry with neutrons is unique in that

1. It involves the coherent splitting a single particle wave
2. Only single particle interference is observed
3. The neutron has a spin and can be polarized to add another degree freedom
4. It can be used to verify some clauses of foundations as well as probe materials

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Much development has lead to the discovery of subspaces encoded in a neutron interferometer in which information is shielded from vibrational noise, commonly referred to as decoherence-free subspace. Some of these work can be found in this arXiv article and references therein. Another interesting work is that of controlling the spin-orbit of a neutron wavepacket. These advancement has led to research progress with potential to probe properties of materials, including skyrmions.

Below is a cartoon of the propagation of a wave through a neutron interferometer.Animation of NI. The signal is chacterized by the value of the contrast. The contrast is defined by the normalized intensity (Imax-Imin)/(Imax+Imin). Below is s typical figure. I in the intensity in either of the ports at the output hisorically referred to as the O- and H-beams. See below for their variation

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Project folder

In these folders are programmed to simulate the propagation of a wave via a neutron interferometer. The wave is modelled in a similar to a quantum walk. An incident wave propagates through a lattice and spreads into a multi-ray limited only by the spatial coherence of the neutron wavepacket. The projects included in these folders are

• Simulation of beam profiles
• Noise effect in a NI

The effect of noise can be modelled as shown in work published paper available on at the at University of Waterloo Repository

The effect of noise can be modelled as following ().