THIS GRANT IS A CONTINUATION OF N000141410802 - Basic science with an ultracold molecule clock: forbidden transitions, nonadiabatic physics, and precision metrology

Approach:This section describes the progress to be made in the course of the next three years on the Sr2 molecular lattice clock. In contrast to work described in Sec. 1.3, these experiments involve two-photon transitions that connect vibrational levels within the ground state (as illustrated in Fig. 8(a)) via intermediate states belonging e.g. to the excited 0+u potential. In the ?high-precision? mode, selected pairs of levels can be measured very accurately to improve model-independent laboratory limits on __ =_ (Sec. 1.4.1); in the ?high-speed? mode, many levels can be measured with a good precision, setting a constraint on nm-scale mass-dependent interactions and quantifying the applicability of the BO approximation (Sec. 1.4.2).Objective:This proposal outlines the goals of high-resolution laser spectroscopyto carry out tests of fundamental laws that may affect important metrological applications, and to advance basic molecular physics.Many new techniques have recently become available to produce and control ultracold molecules for a variety of applications. We have developed a method of creation and high-resolution imaging of a new class of molecules in an optical lattice trap. These ultracold diatomic strontium molecules possess several interesting properties that open the door to new science and a new level of control in molecule manipulation and probing, both in their ground and excited electronic statesNaval Relevance:The main goal of the ONR Atomic, Molecular and Quantum Physics Program is to ?advance navigation, timekeeping and sensing technology by investment in long-range, fundamental research?. The work proposed here perfectly fits this mission, being fundamental cutting-edge research on the interface of ultracold molecular science and high-precision measurement. Timekeeping (and hence navigation) is addressed explicitly in this proposal, and we describe an important addition to the global toolbox of fundamental quantum clock-making. The outstanding degree of control exerted over our lattice-trapped molecules is a starting point for many sensing applications, and in fact one of the proposed directions involves a greatly improved sensitivity to tiny nanometer-scale mass-dependent forces.