Neutron Interferometry at the National Institute of Standards and Technology

C J Wood,D Sarenac,M Arif,D G Cory,D A Pushin,M G Huber,C B Shahi,J Nsofini

doi:10.1155/2015/687480

Abstract

Neutron interferometry has proved to be a very precise technique for measuring the quantum mechanical phase of a neutron caused by a potential energy difference between two spatially separated neutron paths inside interferometer. The path length inside the interferometer can be many centimeters (and many centimeters apart) making it very practical to study a variety of samples, fields, potentials, and other macroscopic medium and quantum effects. The precision of neutron interferometry comes at a cost; neutron interferometers are very susceptible to environmental noise that is typically mitigated with large, active isolated enclosures. With recent advances in quantum information processing especially quantum error correction (QEC) codes we were able to demonstrate a neutron interferometer that is insensitive to vibrational noise. A facility at NIST’s Center for Neutron Research (NCNR) has just been commissioned with higher neutron flux than the NCNR’s older interferometer setup. This new facility is based on QEC neutron interferometer, thus improving the accessibility of neutron interferometry to the greater scientific community and expanding its applications to quantum computing, gravity, and material research.

Highlights

The first single crystal neutron interferometer of Mach-Zehnder type was demonstrated by Rauch et al in 1974 [1]
The Neutron Interferometer and Optics Facility (NIOF) at NIST was built during the construction of the guide hall with vibration isolation in mind
It is placed on a separate foundation from the guide hall floor and consists of two vibration isolation stages

Summary

Introduction

The first single crystal neutron interferometer of Mach-Zehnder type was demonstrated by Rauch et al in 1974 [1]. A few months later Colella, Overhauser, and Werner studied the effects of gravity on a neutron by tilting the interferometer and observing a gravity induced phase shift [2]. In subsequent years the experiment was improved and repeated several times with thorough studies of systematic uncertainties (such as Sagnac effect and crystallographic stress [3,4,5,6]). In recent years there has been renewed interest in use of single crystal neutron interferometry to study gravity [7, 8] and in proposals for searching for non-Newtonian gravity [9], dark energy [10, 11], and other forces [12]

Neutron Interferometer and Optics Facility at NIST

Equivalence of a Neutron Interferometer and Light Mach-Zehnder Interferometer

Coherence and QIP

A New Beam Line