mrfmsim 0.4.2

Simulate magnetic resonance force microscopy experiments.

mrfmsim is a Python framework for simulating magnetic resonance force microscopy (MRFM) experiments. The package is based on the mmodel framework, which provides modular modeling capabilities for the experiments.

This mrfmsim package contains tools to simulate signals in a Magnetic Resonance Force Microscope (MRFM) [1] [2] [3] experiment. The code in the package simulates signal from electron spins, particularly the nitroxide spin radical “TEMPO” to selected nuclear spins (1H, 19F, and 71Ga).

The package host variety of MRFM experiments with the tip-on-cantilever setup. It can simulate signals from both Curie-law spin magnetization and spin fluctuations (in the small polarization limit); and can simulate force experiments and force-gradient experiments (in the small-cantilever-amplitude limit and without the small amplitude approximation — in the large amplitude limit). It can simulate signal with the cantilever and field-aligned in both the hangdown [4] and SPAM [5] [6] experimental geometries.

Quickstart

Installation

mrfmsim installation

To install the package, run:

pip install mrfmsim

For development from a cloned repository, run:

pip install .

Graphviz installation

Graphviz is required only for graph visualization: Graphviz Installation For Windows installation, please choose “add Graphviz to the system PATH for all users/current users” during the setup.

For macOS systems, sometimes brew install results in an unexpected installation path, it is recommended to install with conda:

conda install -c conda-forge pygraphviz

Examples and documentation

The full documentation is available at mrfmsim documentation. Step-by-step examples are available in the overview documentation, including a downloadable overview notebook. Detailed experiment examples are documented in the experiment pages.

Tests

To run the tests locally:

python -m pytest

To test in different environments:

tox

Contributing

We welcome contributions! Please see our Contributing Guide for details on how to follow our development guidelines and submit pull requests.

References

[1]

Sidles, J. A.; Garbini, J. J.; Bruland, K. J.; Rugar, D.; Züger, O.; Hoen, S. & Yannoni, C. S. “Magnetic Resonance Force Microscopy”, Rev. Mod. Phys., 1995, 67, 249 - 265 [10.1103/RevModPhys.67.249].

[2]

Kuehn, S.; Hickman, S. A. & Marohn, J. A. “Advances in Mechanical Detection of Magnetic Resonance”, J. Chem. Phys., 2008, 128, 052208 [10.1063/1.2834737]. OPEN ACCESS.

[3]

Poggio, M. & Degen, C. L. “Force-Detected Nuclear Magnetic Resonance: Recent Advances and Future Challenges”, Nanotechnology, 2010, 21, 342001 [10.1088/0957-4484/21/34/342001].

[4]

Mamin, H. J.; Budakian, R.; Chui, B. W. & Rugar, D. “Detection and Manipulation of Statistical Polarization in Small Spin Ensembles”, Phys. Rev. Lett., 2003, 91, 207604 [10.1103/PhysRevLett.91.207604].

[5]

Marohn, J. A.; Fainchtein, R. & Smith, D. D. “An Optimal Magnetic Tip Configuration for Magnetic-Resonance Force Microscopy of Microscale Buried Features”, Appl. Phys. Lett., 1998, 73, 3778 - 3780 [10.1063/1.122892]. SPAM stands for Springiness Preservation by Aligning Magnetization.

[6]

Garner, S. R.; Kuehn, S.; Dawlaty, J. M.; Jenkins, N. E. & Marohn, J. A. “Force-Gradient Detected Nuclear Magnetic Resonance”, Appl. Phys. Lett., 2004, 84, 5091 - 5093 [10.1063/1.1762700].