Quantum walks and wavepacket dynamics on a lattice with twisted photons

Area of Science:

• Quantum physics
• Photonics
• Quantum information science

Background:

• Quantum walks are crucial for simulating quantum systems, entanglement, and computation.
• Previous photonic implementations relied on complex multipath interferometers.
• A need exists for more efficient and versatile photonic quantum walk platforms.

Purpose of the Study:

• To experimentally realize a discrete quantum walk in the orbital angular momentum (OAM) space of light.
• To develop a novel photonic platform for quantum simulations that overcomes limitations of existing methods.
• To explore band structure and topological features using this new platform.

Main Methods:

• Experimental implementation of a discrete quantum walk using the OAM of light.
• Utilizing a single light beam, avoiding interferometers.
• Flexible control over input and output superposition states.
• Simulating quantum dynamics of Gaussian wavepackets to explore band structure.

Main Results:

• Successful experimental realization of a discrete quantum walk for single and two photons in OAM space.
• Demonstration of a compact and scalable photonic implementation requiring linear optical resources.
• Exploration of system band structure and spin-orbit topological features.
• Validation of a versatile platform for quantum simulations.

Conclusions:

• A novel and versatile photonic platform for discrete quantum walks has been demonstrated.
• This approach offers advantages in scalability, resource efficiency, and control over previous interferometric schemes.
• The platform facilitates advanced quantum simulations, including the study of topological phenomena in photonic systems.