Low-frequency NMR and NQR with a dc SQUID amplifier
A sensitive Fourier-transform spectrometer based on a dc SQUID (Superconducting QUantum Interference Device) has been developed for the direct detection of nuclear magnetic resonance (NMR) in zero applied magnetic field and pure nuclear quadrupole resonance (NQR) at low frequencies. The motivation to detect zero field NMR and NQR is to provide a new high resolution spectroscopy technique at frequencies below 200 kHz to study ultra-weak interactions in chemicals and materials. By comparing the sensitivity of a SQUID amplifier with that of a conventional semiconductor amplifier, it is shown that a SQUID amplifier is essential for the direct detection of low frequency resonant signals. The spectrometer has a frequency response extending from about 10 to 200 kHz, and a recovery time (after the magnetic pulse is removed) of about 50 {mu}s. The spectrometer is used to detect NMR spectra from Pt and Cu metal powders in a magnetic field of 6 mtesla, and NQR spectra from {sup 2}D in a tunneling methyl group and {sup 14}N in NH{sub 4}ClO{sub 4}. Finally, the zero field NMR spectrum from a quantum tunneling methyl group is calculated. 25 refs., 34 figs., 2 tabs.
- Research Organization:
- Lawrence Berkeley Lab., CA (USA)
- Sponsoring Organization:
- USDOE; USDOE, Washington, DC (USA)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 5775965
- Report Number(s):
- LBL-30096; ON: DE91011829
- Resource Relation:
- Other Information: Thesis (Ph.D.)
- Country of Publication:
- United States
- Language:
- English
Similar Records
Nuclear magnetic resonance with dc SQUID (Super-conducting QUantum Interference Device) preamplifiers
Nuclear magnetic resonance with dc SQUID preamplifiers
Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COPPER
NUCLEAR MAGNETIC RESONANCE
NITROGEN 14
NUCLEAR QUADRUPOLE RESONANCE
PLATINUM
POWDERS
AMMONIUM COMPOUNDS
FOURIER TRANSFORM SPECTROMETERS
MAGNETIC FIELDS
METHYL RADICALS
SQUID DEVICES
TUNNEL EFFECT
ZERO SOUND
ALKYL RADICALS
ELECTRONIC EQUIPMENT
ELEMENTS
EQUIPMENT
FLUXMETERS
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
MEASURING INSTRUMENTS
METALS
MICROWAVE EQUIPMENT
NITROGEN ISOTOPES
NUCLEI
ODD-ODD NUCLEI
PLATINUM METALS
RADICALS
RESONANCE
SPECTROMETERS
STABLE ISOTOPES
SUPERCONDUCTING DEVICES
TRANSITION ELEMENTS
400101* - Activation
Nuclear Reaction
Radiometric & Radiochemical Procedures
426001 - Engineering- Superconducting Devices & Circuits- (1990-)