Integrated spin-QED platform with spatio-temporal delivery of effective magnetic fields for all-optical qubit control
Abstract
The most promising platforms for quantum systems are circuit QED , ion traps , spins in silicon, cold atom arrays and defect centers in diamond /silicon carbide . As the number of qubits are scaled up, these near-term systems will have applications in quantum simulation , many-body localization and exotic phases of matter, quantum memories, quantum sensing , single-shot quantum detection , quantum networks and eventually error corrected quantum computing. Integration of sources, control beams and high efficiency detectors on the same miniaturized platform can pave the way for advanced qubit control protocols, efficient read-out schemes as well as error correction codes towards robust scalable quantum systems. One formidable challenge is the targeted spatio-temporal application of magnetic fields and microwave (MW) fields especially for spin qubit control. Bulky microwave antennas used for generating MW pulses and the large spatial mode volume of low frequency electromagnetic radiation are a significant obstacle towards scalability. Bulky magnets cannot be switched and MW antennas do not provide qubit addressability which is crucial for scalability and isolation of qubits. Targeted magnetic fields and MW pulse sequences are required for devices such as circulators as well as for qubit rotation protocols in spin qubits. Thus, a fundamentally new approach to targeted on-demand switchable magnetic field delivery to a precise nanoscale spatial location can provide a disruptive advance for qubit rotation and control. The goal of this three year program is to develop an integrated spin QED platform which exploits the local photon spin density of optical frequency light waves to provide targeted effective magnetic field delivery to spin qubits. The photon spin density is a local vector physical property associated with light that has recently risen to the fore-front of nanophotonics. Fundamentally different from orbital angular momentum carried by free-space optical beams and whispering gallery mode resonators, the spin angular momentum is an intrinsic degree of freedom of light. The striking property that distinguishes it from OAM is that it can be controlled locally within sub-wavelength mode volumes. Our first step is to develop a theoretical framework for on-chip few qubit systems interacting with the nanoscale sub-wavelength photonic spin density. This will help with designing optimized spatio-temporal wavepackets that can be used for targeted effective magnetic field delivery and all-optical qubit driving protocols. In the long run, we believe our efforts can lead to new spatio-temporal all optical qubit driving protocols to dynamically decouple quantum information from a noisy environment. One major advantage of integrated spin QED is the all-dielectric, non-metallic, non-magnetic platform which preserves the intrinsic spin qubit coherence times and allows for all-optical qubit control. A major milestone will be the achievement of effective magnetic fields on-chip solely through an all-optical route with picojoule level gate operations. This can pave the way for future scalable spin qubit based quantum systems.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 25, 2021
- Source ID
- W911NF2110287
Entities
People
- Zubin Jacob
Organizations
- Army Contracting Command
- Purdue University
- United States Army