Skills & Expertise

Notable Accomplishments

Wrote significant portions of the disk defragmenter in Windows 2000/XP.
Wrote software in use by many Banks (Chase, Wells Fargo, Citi etc.)
Worked on Chile’s internet backbone (1998)
Co-holder of two patents, including one sold to Square.
Helped measure the chemical state of iron in interstellar space.
Determined that several particles likely from interstellar space are crystalline.
Helped double the number of interstellar particles found using a Convolutional Neural Net.
Helped date the age of Jupiter using 26Al->26Mg radioisotope decay from comet Wild 2. ⚛
Identified that rocky objects in comet Wild 2 formed in high pressure and temperature environments.
Identified multiple water-based geological events on asteroid Ryugu’s parent.
Identified molecular carbonate water evaporation residue in Bennu samples.
Helped pioneer the use of several techniques for astromaterials including nanoIR and STEM/EDS tomography.
Co-founder of FIRST robotics Team 980 (which has gone to the world championship). (FIRST Team 980)

Scanning electron microscopy (SEM) and focused ion beam microscopy (FIB) imaging and analysis for high resolution (nm) and high contrast using various detectors including Everhart-Thornley secondary detectors, solid state, and scintillator based backscatter detectors, and continuous dynode electron multiplier (CDM) technology.
Familiarity with many models including Zeiss, Hitachi, JEOL, FEI, and Tescan.
Energy dispersive spectroscopy (EDS) for elemental quantification and mapping.
Electron channeling and electron backscatter diffraction (EBSD) for mineral identification and orientation analysis.
Low vacuum, low voltage, and other charge reduction techniques.
Air free sample preparation for samples that cannot be exposed to oxygen.
Ion milling and deposition using gas insertion systems (GIS).
Sample preparation methods including polishing, ion milling, coating, cleaving, FIB, etc.

High contrast imaging including energy filtered imaging, plasmonic imaging, and darkfield.
Electron diffraction including selected area diffraction for large samples (100’s of nanometers and up) and convergent beam diffraction for small samples. These allow analysis of crystal identification, orientation, thickness, twinning, etc.
Electron Energy Loss Spectroscopy (EELS) and energy filtered imaging (EFTEM) of core-loss states which allows quantification of low-Z elements and spectroscopic information (similar to soft X-ray XANES).
EELS of the low energy regime which allows determination of optical constants of materials, and determination of electron mobilities.
Tomography for analysis of 3D structures.
EDS for elemental mapping and quantification, including elemental tomography.
Atom location by channeling enhanced microanalysis (ALCHEMI) for determination of atom site locations.
High resolution imaging (atomic scale) including exit wave reconstruction via focus stacks.
Familiarity with many models and configurations including Philips, JEOL, and Zeiss.
Sample prep including ultramicrotomy, dimpling and polishing, ion milling, cleaving, dispersions, etc.
Air free analysis.

X-ray Diffraction for single crystal, polycrystal, monochromatic, Laue, etc. Crystal identification, particle size analysis, strain analysis, diffraction topography, etc. to fully characterize the properties of various crystals.
X-ray fluorescence (XRF) under various geometries including grazing exit and trace element identification.
X-ray absorption fine structure spectroscopy (XANES) of elements on soft and hard x-ray beamlines. Determination of site symmetry and oxidation states of elements from XANES.
Extended X-ray absorption fine structure (EXAFS) of elements on hard x-ray beamlines. Detailed determination of coordination environments around specific atoms.
Scanning Transmission X-ray Microscopy (STXM) for nano-scale imaging of samples in the soft X-ray regime. Quantification of trace elements in complex assemblages and analysis of materials through soft X-ray XANES and EXAFS.
Ptychography for high resolution STXM analysis.
X-ray magnetic circular dichroism (XMCD) using Photoemission electron microscopy (PEEM) for imaging of magnetic materials at the nanoscale.
Fourier Transform Infrared Spectroscopy (FTIR) for identification of functional groups in silicates and organics.
Nano-IR using the synchrotron as an IR source.

I have experience with data acquisition and/or data analysis on the following beamlines:

Advanced Light Source (ALS)

European Synchrotron Radiation Facility (ESRF)

AFM-IR for analysis of sub-diffraction-limited infrared spectra using the Bruker nanoIR3-s including both contact mode and REINS.
SNOM for analysis of full optical constants (real and imaginary) using nearfield infrared spectroscopy with resolution down to a few nanometers.
Synchrotron and laser based light sources.
AFM imaging and data processing including use of phase and height analysis.

Chandra X-ray observatory including the CIAO data analysis pipeline (Westphal et al. 2019).
XMM-Newton X-ray observatory including the SAS data analysis pipeline.
Machine learning and data analysis of X-ray datasets.

Plane wave and local basis density functional theory (DFT) including Quantum Expresso (QE), VASP, exciting, and Orca.
Simulation of basic structures and material constants such as bulk modulus.
Simulation of infrared vibrational modes.
Simulation of K-edge X-ray spectra via XSPECTRA.
Simulation of L-edge X-ray spectra via ROCIS.
Molecular dynamics using LAMMPS and Carr-Parinello MD using QE.
Click to view simulation video

X-ray spectra simulation and analysis using FEFF and Demeter.
Ab-initio Simulation of thermodynamic constants.
Calculation of thermodynamic parameters using Gibbs minimization and CALPHAD including MELTS, Thermocalc, HSC Chemistry, and my own software.

High performance computing including the Perlmutter supercomputer (#5 on the Top 500 list, Nov 2021), Vulcan and Etna clusters located at the Lawrence Berkeley National Laboratory.
Familiarity with MPI, OpenMP, distributed file systems etc.
Embedded environments including PIC, Cypress PSOC, RP2040 etc.
PCs (Windows, Mac OS, Linux).
Once wrote my own boot sector for fun.

Fundamental electronics including transistor structure and design, solid state physics, sensors and instrumentation. I did rudimentary fabrication of BJTs, FETs, and MEMS in college from design through analysis including FIBing and TEM analysis of a silicon transistor.
Analog, digital and mixed signal electronics, with experience weighted more heavily towards analog/mixed.
High voltage electronics.
PCB design.
Motor drivers, etc.
Robotics