Research

Quantum dynamics, spectroscopy, and molecular polaritons.

I study how strong light–matter coupling reshapes molecular dynamics, spectroscopy, and transport, then build the theoretical and computational tools needed to simulate those processes.

Molecular ensemble collectively interacting with a standing optical cavity field
01

Light–matter interaction

Cavity-modified chemistry

When molecules exchange energy coherently with a confined photon, the useful degrees of freedom become hybrid light–matter states.

I develop quantum-dynamics frameworks for molecular ensembles under strong coupling. The work connects microscopic models to linear and two-dimensional spectra, revealing polaron decoupling, long-lived polaritonic coherence, motional narrowing, and collective many-body behavior in vibrational strong coupling.

  • Exciton–polaritons
  • Vibrational strong coupling
  • Cavity QED
  • Collective coupling
Ultrafast pulses and wavepacket dynamics resolved as a two-dimensional spectrum
02

Reading molecular motion

Condensed-phase spectroscopy

Spectra are not only peaks. Their shapes, cross-peaks, and waiting-time evolution encode how molecules move and exchange energy.

I formulate response functions in terms of trajectory-based dynamics and design efficient strategies for computing linear and nonlinear spectra of systems inseparable from their fluctuating environments. Two-dimensional electronic spectroscopy provides a particularly direct view of coherence, coupling, and energy-transfer pathways.

  • Linear absorption
  • 2DES
  • Response functions
  • Lineshape analysis
Coherent quantum wavepacket coupled to harmonic modes and trajectory paths
03

Dynamics in context

Mixed quantum–classical dynamics & open quantum systems

The environment is not background noise. It controls decoherence, relaxation, transport, and the observables measured in spectroscopy.

I develop trajectory methods combining partial linearized density-matrix dynamics with Lindblad formalisms so that Markovian and non-Markovian dissipation can be handled in a common simulation. Related work explores spin mapping, polaron and Schrieffer–Wolff transforms, and reaction-coordinate mappings.

  • PLDM
  • Lindblad dynamics
  • Mapping methods
  • Structured baths
Wavepacket, sparse transforms, and parallel computational blocks
04

Scaling the calculation

Numerical methods for quantum dynamics

A physical theory becomes useful only when its calculation remains accurate and affordable at the scale of the experiment.

I develop sparse propagation schemes, Chebyshev expansions, symmetry and unique-variable reductions, and high-performance implementations in Python, C++, and Julia. The objective is to retain the relevant quantum structure while making ensemble and nonlinear-spectroscopy calculations tractable.

  • Chebyshev propagation
  • HEOM
  • HPC & GPU
  • Machine learning

Computational workflow

How the calculations are organized.

  1. 01

    Model

    Identify the smallest Hamiltonian and bath that preserve the physics of interest.

  2. 02

    Propagate

    Choose a dynamics method that balances quantum accuracy, scale, and observable.

  3. 03

    Measure

    Construct linear or nonlinear response functions in the experimental language.

  4. 04

    Interpret

    Connect spectral signatures back to coherence, transport, and molecular structure.