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A firmware-defined digital direct-sampling NMR spectrometer for condensed matter physics
M Pikulski1, T Shiroka1, H-R Ott1
1Laboratorium für Festkörperphysik, ETH Hönggerberg, CH-8093 Zürich, Switzerland and Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland.
The Review of Scientific Instruments
|October 3, 2014
Summary
A new digital, broad-band nuclear magnetic resonance (NMR) spectrometer was developed for condensed matter research. This flexible, software-defined instrument offers competitive performance and easy replication for advanced studies.
Area of Science:
- Condensed Matter Physics
- Spectroscopy
- Digital Instrumentation
Background:
- Traditional Nuclear Magnetic Resonance (NMR) spectrometers can be complex and expensive.
- There is a need for flexible, adaptable, and cost-effective instrumentation for condensed matter research.
Purpose of the Study:
- To design and implement a novel digital, broad-band NMR spectrometer.
- To create a versatile and extensible platform for condensed matter probing.
- To demonstrate competitive performance compared to conventional NMR systems.
Main Methods:
- Utilized direct sampling in transmission and reception.
- Employed a single, commercially available signal processing device with a Field-Programmable Gate Array (FPGA).
- Defined spectrometer functions via FPGA firmware and application software.
Main Results:
- The digital NMR spectrometer operates up to 400 MHz (800 MHz with undersampling).
- Features digital down-conversion with a ±10 MHz passband and supports high repetition rates.
- Demonstrated competitive performance through test data, comparable to conventional designs.
Conclusions:
- The developed software-based NMR spectrometer offers flexibility, fast replication, and extensibility.
- Components can be reused for other projects, enhancing value.
- The system provides a viable, high-performance alternative for condensed matter research.
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