## Welcome

We are a group of theoretical physicists and chemists based at the National Research Council of Canada (NRC) in the Steacie Laboratory, formerly known as the Steacie Institute for Molecular Sciences. The Laboratory is named after Dr. E.W.R. Steacie, F.R.S. (1900-1962) who was President of NRC from 1952 to 1962; he introduced the Postdoctorate Fellowship scheme at NRC. Our research programs cover a wide range of topics within chemical physics, AMO physics, quantum information, and material sciences.

## Highlights

### High-Dimensional Intra-City Quantum Cryptography with Structured Photons

Quantum key distribution (QKD) promises information-theoretically secure communication and is already on the verge of commercialization. The next step will be to implement high-dimensional protocols in order to improve noise resistance and increase the data rate. Hitherto, no experimental verification of high-dimensional QKD in the single-photon regime has been conducted...

### Full-dimensional treatment of short-time vibronic dynamics in a molecular high-order-harmonic-generation process in methane

The method of multiconfigurational strong-field approximation with Gaussian nuclear wave packets is developed to study the effect of nuclear motion for molecules in strong laser fields, where an investigation on the polyatomic molecule methane reveals that the high-order-harmonic generation contains signatures of field-free vibronic dynamics at the conical intersection and...

### Entanglement between more than two hundred macroscopic atomic ensembles in a solid

Multiparty entanglement is generally fragile and difficult to quantify. Dicke states are multiparty entangled states where a single excitation is delocalized over many systems. Building on previous work on quantum memories for photons, we create a Dicke state in a solid by storing a single photon in a crystal that...

### Solving the Schrödinger Equation with deep neural networks

A deep (convolutional) neural network is trained to predict the ground-state energy of an electron in two-dimensional potentials. The machinery of deep learning is developed to learn the mapping between potential and energy, which bypasses the need to numerically solve the Schrödinger equation and the need for computing wave functions....

### Signatures of the continuum electron phase in molecular strong-field photoelectron holography

Laser-driven electron recollision is at the heart of the rapidly growing field of attosecond science. The recollision wavepacket is qualitatively described within the strong-field approximation, which commonly assumes tunnelling ionization and plane-wave propagation of the liberated electron in the continuum. However, with increasing experimental sophistication, refinements to this simple model have...

### Direct imaging of rotational wave-packet dynamics of diatomic molecules

We use linearly polarized 45 fs pulses to create rotational wave packets in N2 and O2. We Coulomb explode molecules with a high-intensity circularly polarized pulse and use an ion imaging detector to measure a series of two-dimensional projections of the wave packet’s angular distribution in 27 fs increments. We highlight the evolving wave...