Nuclear Spin Gyroscope using Neon-21 atoms
Abstract
Nuclear Spin Gyroscope using Neon-21 atomsMichael RomalisDepartment of PhysicsPrinceton UniversityProposal to Fundamental Research in Atomic, Molecular and Quantum PhysicsAbstractPrinceton University considers the research listed herein to be fundamental research asprescribed in NSDD189. We anticipate an award that may include foreign nationals (non-USpersons) and may be freely published.Inertial rotation sensors serve a crucial role for precision navigation and a number of differenttechnologies have been explored for this purpose. One of the approaches that recently attractedincreased attention is based on precession of nuclear spins. Nuclear spin gyroscopes provide aquantum-mechanically stable method for sensing inertial rotation based on intrinsic angularmomentum of nuclear spins. Nuclear spin gyroscopes have relatively simple implementation andcan be scaled to down to centimeter size while retaining navigation-grade sensitivity. Such smallsize sensors become increasingly important for various autonomous applications. However, sofar there is no approach that provides both short-term and long-term stability.We propose to develop new techniques using Ne-21 atoms which have not been previously usedfor nuclear spin gyroscopes. Ne-21 atoms combine many advantageous properties, includinglow sensitivity to magnetic fields and long spin coherence times. We will explore two methodsfor using Ne, partially based on our prior research, in order to realize a gyroscope that combineslow angle random walk (ARW) noise and a small bias drift with low power and small size.One method uses a comparison between spin precession of Rb atoms and Ne-21 atoms. This isan efficient method since Rb atoms are already introduced into the cell in order to polarize Ne-21atoms by spin exchange. With a similar approach our group has demonstrated navigation-gradeARW performance, but the long-term bias drift remained too high for practical applications. Wepropose a new method that can eliminate long-term drift by allowing one to distinguish betweenoptical and atomic signals.A second approach is based free precession of two nuclear spin species, for example He-3 andNe-21. In the past our group has explored a similar approach using He-3 and Xe-129 spins. Wehave shown that free precession measurements give good long-term stability on a time scale of24 hours. However, short term ARW performance was just approaching navigation-gradeperformance. We expect that Ne-21 will provide much better performance because the spincoherence time for Ne-21 is more than an order of magnitude longer than for Xe-129.Both experimental investigations will be largely conducted using existing apparatus, so weexpect to realize both approaches within 2 years. We will characterize the performance of sensorprototypes with an active volume of less than 1 cm3. Successful demonstration of navigationgradeprecision and accuracy will point to a practical path for miniature inertial navigationsystems.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 03, 2017
- Source ID
- N000141712251
Entities
People
- Michael Romalis
Organizations
- Office of Naval Research
- Trustees of Princeton University
- United States Navy