Introduction
I am a graduate student in the Department of Physics at Stanford University. As part of the research group of Dr. Kent Irwin, I focus on the application of superconducting detectors to X-ray spectroscopy.
Working at the Stanford Synchrotron Radiation Lightsource (SSRL), I operate a 240 pixel transition-edge sensor (TES) array in support of a diverse user program at beamline 10-1. TES devices have emerged in the soft X-ray regime as moderate-resolution, high-throughput spectrometers that are particularly suited to measure dilute and damage-sensitive samples. My role as an instrumentation scientist has focused on fast data processing, instrument calibration, and ease-of-use for users.
My research into spectroscopy focuses on using partial-fluorescence-yield X-ray absorption spectroscopy to probe electronic structure in transition-metal complexes. Transition metals play a critical role in proteins such as hemoglobin and photosystem-II, catalysts, and batteries. In all of these systems, metals have a powerful ability to change oxidation states, store energy, and shuttle electrons around. X-ray spectroscopy allows us to directly probe the properties of transition metals that make them so useful for chemistry and biology.
Selected Publications
- Titus, C. J., et al. “Operational optimizations for TES detectors at a femtosecond X-ray laser”, J. Low Temp. Phys. (2020)
- Lee, S.-j., Titus, C. J., et al. “Soft X-ray spectroscopy with transition-edge sensors at Stanford Synchrotron Radiation Lightsource beamline 10-1”, Rev. Sci. Instrum. 90. (2019)
- Titus, C. J., et al. “Error-Correcting Codes for Code-Division Multiplexed TES Detectors”, J. Low Temp. Phys., 193(34). (2018)
- Titus, C.J. et al, "L-edge spectroscopy of dilute, radiation-sensitive systems using a transition-edge-sensor array", J. Chem. Phys. 147, 214201 (2017)
A full list of my publications is avaliable via Google Scholar and ORCID
Conferences
Past Presentations
- "Conference Talk: “Lessons from the beamline: Implementing a TES spectrometer as a facility instrument at SSRL for x-ray measurements in chemistry, biology, and materials science”, 18th International Conference on Low Temperature Detectors, Milan, Italy (July 2019)
- Conference Poster: “2p3d RIXS as a complement to L-edge XAS”, Inelastic X-ray Scattering 2019, Stonybrook, New York, USA (June 2019)
- Conference Talk: “Realizing the promise of Transition Edge Sensors for X-ray Spectroscopy”, Applied Superconductivity Conference, Seattle, Washington, USA (November 2018)
- Conference Poster: “TES x-ray detectors for high efficiency spectroscopy of hemoglobin and other proteins”, 17th International Conference on Low Temperature Detectors, Kurume, Japan (July 2017)
- Conference Talk: “Ultrasensitive probing of local electronic structure in the soft X-ray regime”, Materials Research Society, Phoenix, Arizona, USA (April 2017)
Code
I maintain and develop codes for doing calculations of X-ray spectra. All codes are provided with no guarantees as to accuracy, documentation, user-friendliness, etc. They are provided as-is. Please contact me with any questions or corrections.
Repositories
- TTMult: Source code for the classic "TTMult" set of programs, comprised of Cowan's atomic code, Butler's group theory code, and Thole's configuration-interaction code for crystal-field and ligand-field calculations. Some errors have been fixed, and makefiles are provided for linux and Windows systems.
- pyttmult: A python interface to TTMult that allows TTMult programs to be called either via command line scripts or python functions.
Contact Me
You can contact me at ctitus [at] stanford.edu