PhD Proposal: Carson Evans
Location
Physics : 401
Date & Time
May 4, 2022, 1:30 pm – 3:00 pm – Canceled
Description
ADVISOR: Dr. Todd Pittman
TITLE: Experimental Storage of Entangled Photons in Cyclical Quantum Memories
ABSTRACT: One of the main challenges in the field of quantum information is the difficulty of storing qubits while maintaining their quantum state. Since the realization of quantum computing, a great deal of work has gone into the technology required to create, maintain, and manipulate quantum states. At present, there are numerous approaches to representing qubits with various physical systems (e.g., particle spins, ions, superconducting currents, etc.). Our group is focused on using individual photons as our qubits with the information encoded in the polarization degrees of freedom. Photons are ideal candidates for sending and receiving information as they are self-propagating and tend to not interact heavily with the environment due to their charge-free nature. One challenge facing the use of photons is the need to store them for later use without destroying their non-classical state. A considerable amount of work has gone into finding an ideal candidate for optical quantum memories of which we will briefly review, but we hope to go beyond individual quantum memories.
Here I propose research to demonstrate the active storage and release of two polarization-entangled photons generated by spontaneous parametric down conversion in separate quantum memories, confirming the ability to maintain entanglement between a pair of photonic qubits while stored independently. We will use a Cyclical Quantum Memory (CQM) which is a device that uses a simple free-space Sagnac loop, polarizing beamsplitter, and Pockels cell to actively store arbitrary photonic qubits encoded in their polarization states and release them on-demand. Additionally, we plan to investigate the various sources of noise within one CQM and the role they play in the more complicated system of two entangled CQMs. We believe this will be a tangible step forward in the development of quantum information devices as well providing insight into the nature of quantum entanglement.
TITLE: Experimental Storage of Entangled Photons in Cyclical Quantum Memories
ABSTRACT: One of the main challenges in the field of quantum information is the difficulty of storing qubits while maintaining their quantum state. Since the realization of quantum computing, a great deal of work has gone into the technology required to create, maintain, and manipulate quantum states. At present, there are numerous approaches to representing qubits with various physical systems (e.g., particle spins, ions, superconducting currents, etc.). Our group is focused on using individual photons as our qubits with the information encoded in the polarization degrees of freedom. Photons are ideal candidates for sending and receiving information as they are self-propagating and tend to not interact heavily with the environment due to their charge-free nature. One challenge facing the use of photons is the need to store them for later use without destroying their non-classical state. A considerable amount of work has gone into finding an ideal candidate for optical quantum memories of which we will briefly review, but we hope to go beyond individual quantum memories.
Here I propose research to demonstrate the active storage and release of two polarization-entangled photons generated by spontaneous parametric down conversion in separate quantum memories, confirming the ability to maintain entanglement between a pair of photonic qubits while stored independently. We will use a Cyclical Quantum Memory (CQM) which is a device that uses a simple free-space Sagnac loop, polarizing beamsplitter, and Pockels cell to actively store arbitrary photonic qubits encoded in their polarization states and release them on-demand. Additionally, we plan to investigate the various sources of noise within one CQM and the role they play in the more complicated system of two entangled CQMs. We believe this will be a tangible step forward in the development of quantum information devices as well providing insight into the nature of quantum entanglement.
