Ph.D. in Theoretical Chemical Physics | Quantum Computing | Scientific Software Developer

I'm a quantum theorist and scientific software engineer with deep expertise in spin dynamics, entangled exciton modeling, and numerical methods for quantum systems. I build theory and software that connect foundational quantum science with real-world quantum technologies—from spin-based qubit control to efficient hybrid DFT simulations.

• 📘 JDE Model for Quantum Information
  Developed the JDE model, a spin-exciton Hamiltonian used to simulate nonadiabatic singlet fission dynamics and entangled quintet states.

• 🎯 Selection Rules via Wigner-Eckart
  Derived symmetry-based transition rules that enable deterministic population of EPR-active sublevels—paving the way for qubit initialization at room temperature.

• ⚡ Multigrid Method for Hybrid DFT
  Developed a new multigrid ISDF approach to drastically reduce CPU and memory costs in periodic DFT calculations. Integrating into PySCF extensions.

• 📈 Simulation-Experiment Synergy
  Matched theory with time-resolved EPR spectra in rigid dimers and crystalline systems using simulated-annealing for spectral fitting.

• Spectroscopy: Time-resolved electron paramagnetic resonance (trEPR), Raman, vibrationally resolved UV-Vis, spatially resolved ultrafast pump-probe microscopy
• Quantum Chemistry:
  • Variational energy minimization, spin Hamiltonians, Dirac-Heisenberg exchange, spin-dipole coupling, zero-field splitting, scaling
  • Coupled systems, entanglement, coherence, clock transitions, quantum beats
  • Population & spin dynamics, diffusion, nonadiabatic transition theory, state-selective relaxation, selection rules
• Electronic Structure:
  • PySCF, Gaussian
  • Hartree-Fock, hybrid DFT, exchange-correlation, periodic boundary conditions, excited state modeling (TD-DFT), k-points
  • Multigrid methods, Fast Fourier Transforms (FFT), matrix decompositions (ID, QRCP, SVD), tensor hypercontraction (THC, rPS), density fitting (RI, ISDF)
• Numerical Methods:
  • Eigensystems, tensor contraction, linear algebra
  • Least-squares optimization, stochastic optimization for non-linear fitting (simulated annealing)
  • Monte Carlo methods, k-means clustering
  • Numerical methods for differential equations, integration, and interpolation
• Programming:
  • Linux, MacOS
  • Bash, vi, SLURM
  • Python, C/C++, Julia, MATLAB, Mathematica, Igor, LabView
  • Numpy, numba, scipy, joblib, matplotlib, pandas, pyfftw, mpi4py, h5py
  • OpenMP, MPI, multi-threading, high-performance computing, compilers, dependency management
  • Software packaging and testing (pip, Pkg.jl), documentation, version control (Git, Github), optimization, benchmarking

• Singlet Fission for Quantum Information: The JDE Model, Sci. Rep. 10, 18480 (2020)
• Entangled Spin-Polarized Excitons from Singlet Fission, Nat. Commun. 14, 1180 (2023)
• Multigrids for Interpolative Separable Density Fitting, J. Phys. Chem. A 128, 7451–7461 (2024)
• Triplet-Pair Spin Signatures, Proc. Nat. Acad. Sci. 119, 29 (2022)

Feel free to reach out!!! kori.smyser@gmail.com