Nuclear Quadrupole Resonance Frequency in Multilayered Cuprates

Nuclear Quadrupole Resonance*

A resonance phenomenon which is closely related to NMR is nuclear quadrupole resonance (NQR), which was discovered in 1950 by Dehmelt and Kruger. All nuclei with a spin > 1 possess in addition to the magnetic moment, an electric quadrupole moment eQ, which measures the deviation of the distribution of the positive charge in the nucleus from spherical symmetry. While e is the elementary charge, ...

Nuclear Quadrupole Resonance Spectroscopy

Low Frequency Nuclear Quadrupole Resonance with SQUID Amplifiers*

The dc SQ U ID (Superconducting QUantum Interference Device) can be configured as an ampli­ fier of spin-echos with a noise temperature of approximately 10 mK (f/1 MHz) at an operating temperature of 1.5 K. A Fourier transform spectrometer based on a SQ U ID with a superconducting input circuit and operated in a flux-locked loop is used to obtain nuclear quadrupole resonance (NQR) spectra in a ...

Nuclear Quadrupole Resonance (paper Ii)

The Polymer Diagnostics Section (Code 6122) of the U.S. Naval Research Laboratory (NRL) has expertise in solid state nuclear magnetic resonance (NMR), magnetic resonance imaging (MRI), and nuclear quadrupole resonance (NQR). In 1983, NRL established an interagency agreement with the Federal Aviation Administration (FAA) to advise the FAA on NMR methods to detect explosives. We were aware of ear...

Nuclear Quadrupole Resonance (paper I)

Nuclear quadrupole resonance (NQR) combines the spatial localization capability and convenience of metal detection or ground-penetrating radar (GPR) with the compound specific detection capability offered by chemical detection techniques. Starting in the mid-1990s, groups at Quantum Magnetics Inc. and the Naval Research Laboratory made considerable improvements in the basic scientific and instr...