title: Coherent NMR Stark spectroscopy.
abstract: We demonstrate phase-coherent Stark effects from a radiofrequency E field at twice the NMR frequency (2ω(0)) of (69)Ga in GaAs. The 2ω(0) phase (ϕ(E)) selects component responses from the nuclear quadrupole Hamiltonian (H(Q)). This is possible by synchronizing few-μs 2ω(0) pulses with an NMR line-narrowing sequence, which averages the Stark interaction to dominate spectra on a background with 10(3)× enhanced resolution. Spectra vs ϕ(E) reveal relative sizes of tensorial factors in H(Q). Comparative modeling and numerical simulations evaluate spectral features unexplained by average Hamiltonian theory, and suggest improvements for quantitative calibration of individual response components. Application of this approach to bulk samples is of value to define Stark responses that may later be used to interrogate the internal electrostatics of structured samples.
authors.affiliation: Department of Chemistry & Chemical Biology and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180, United States.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Tarasek
authors.forename: David J
authors.initials: DJ
authors.lastname: Goldfarb
authors.forename: James G
authors.initials: JG
authors.lastname: Kempf
mesh_terms: D003198:Computer Simulation; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008956:Models, Chemical; D008958:Models, Molecular