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The Quantum Diamond Microscope (QDM)

The application of paleomagnetic techniques to meteorites and rocks of the early Earth has created the need to analyze weakly magnetized samples that are heterogeneous at the <<1 mm scale.  Single chondrules, for example, often have magnetic moments of less than 1x10-13 A m2 and dimensions of several hundred micrometers. 

QDM

The QDM at the Harvard Paleomagnetics Laboratory has achieved spatial resolutions of ~1 µm with moment sensivities of less than 1x10-16 A m2, allowing it to image the magnetic fields generated by individual, single-domain ferromagnetic grains.  These capabilities can be used to directly quantify natural or artificial magnetizations from grain ensembles or identify the mineralogical carriers of observed magnetization.

QDM II

In the lab

Publications:

M.W.R Volk*, R.R. Fu, R. Trubko*, P. Kehayias*, D.R. Glenn*, E.A. Lima. (2022) QDMlab: A MATLAB toolbox for analyzing quantum diamond microscope (QDM) magnetic field maps. Comput. Geosci. 167, 105198.

R. Ebadi, A. Mathur, E.H. Tanin, N.D. Tailby, M.C. Marshall, A.Ravi, R. Trubko*, R.R. Fu, D.F. Phillips, S. Rajendran, R.L. Walsworth. (2021) Ultra-heavy dark matter search with electron microscopy of geological quartz. Phys. Rev. D. 104, 015041.

R.R. Fu, E.A. Lima, M.W.R. Volk*, R. Trubko* (2020) High-resolution moment magnetometry with the quantum diamond microscope. Geochem. Geophys. Geosyst. 21, e2020GC009147. 

E.V. Levine, M.J. Turner, P. Kehayias*, C.A. Hart, N. Langellier, R. Trubko*, D.R. Glenn*, R.R. Fu, R.L. Walsworth (2019) Principles and techniques of the quantum diamond microscope. Nanophotonics 8, 1945-1973. (Physics convention for author order: Walsworth and Fu are paper PIs). 

D.R. Glenn, R. R. Fu, P. Kehayias, D. Le Sage, E. A. Lima, B. P. Weiss, and R. L. Walsworth. "Micrometer‐scale magnetic imaging of geological samples using a quantum diamond microscope." Geochemistry, Geophysics, Geosystems (2017). PDF

R.R. Fu, B.P. Weiss, E.A. Lima, P. Kehayias, J.F. Araujo et al. (2017) Evaluating the paleomagnetic potential of single zircon crystals using the Bishop Tuff.  Earth Planet. Sci. Lett. 458, 1-13. PDF

R.R. Fu, B.P. Weiss, E.A. Lima, R.J. Harrison, X.-N. Bai et al.  (2014) Solar nebula magnetic fields recorded in the Semarkona meteorite.  Science 346, 1089-1092. PDF