Cryogenics for a Quantum Network Testbed
Abstract
Diamond quantum emitters have recently enabled critical milestone experiments showing that this technology is capable of reaching the next stage of functionality: deployment into a coherent quantum network. These milestone experiments include network demonstrations of entanglement-on-demand; exceeding the Òrepeaterless quantum communication boundÓ to realize Òquantum advantageÓ in quantum networks. The further combination of these emitters with photonic integrated circuits (PICs) enables miniaturization of optical quantum circuits because several optic and electronic functionalities can be added on the same chip. These advances are enabled by cryogenic refrigeration which improves qubit coherence by orders of magnitude at temperatures below 4 K. Here we propose to develop a state-of-the-art closed-cycle cryocooler based with a helium sorption fridge to reach sub-Kelvin temperatures with sufficient cooling power for at least 16 qubit channels. This regime will enable quantum network studies based on Group-IV vacancy complexes in diamond, where the decrease in thermal phonon occupation will increase spin coherence times to tens of milliseconds or seconds as needed for applications involving multiple qubits. As an affordable alternative to dilution refrigeration, this sorbtion-based cryosystem will also accelerate research towards scalable quantum devices based on arrays of quantum emitters integrated with photonic integrated circuits. This hybrid system -- combining waveguide-coupled artificial atoms in diamond and III-V quantum dots with photonic circuits -- will enable miniaturization of optical quantum circuits towards scalable applications,with a particular focus on evaluation of routing and efficient quantum information distribution in the context of quantum networking.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 03, 2022
- Source ID
- W911NF2210043
Entities
People
- Dirk Englund
Organizations
- Army Contracting Command
- Massachusetts Institute of Technology
- United States Army