Research Projects
Current Research:
Quantum Sensing with Trapped Ions
When building a quantum sensor, there’s generally a tradeoff between then number of qubits measured in parallel and the quantum coherence and control fidelity. For continous signals, it is favorable to increase the number of sensors and sacrifice fidelity. However, we recently showed theoretically and experimentally that if the signal is intermittent it is necessary to maintain near-unity fidelity.
To this end, I have been developing and integrated photonics platform for parallel control of an array of trapped ions, each trapped in their own potential to limit crosstalk.
References:
1. Quantum Sensing of Intermittent Stochastic Signals Sara Mouradian, Neil Glikin, Eli Megidish, Kai-Isaak Ellers, Hartmut Haeffner, arXiv:2010.03678
Novel Ion Trap Architectures
Trapped ions allow unsurpassed control over their electronic and motional states. Microfabricated traps allow for engineered control of ion position and motion. In a circularly symmetric trap we are developing techniques for coherent control over angular momentum states of ion rings. A second trap with 98 controllable electrodes allows for shuttling, splitting, and merging of strings of ions.
References:
1. Coherent Control of the Rotational Degree of Freedom of a Two-Ion Coulomb Crystal Erik Urban, Neil Glikin, Sara Mouradian, Kai Krimmel, Boerge Hemmerling, Hartmut Haeffner PRL 123 (13), 133202 (2019)
Previous Research:
Integrated Architectures for Quantum Information Processing
Current quantum computing systems are bulky and don't do much. To realize a quantum advantage, we'll need to build, maintain, and control quantum systems of tens, hundreds, and eventually millions of qubits.
Luckily, we can learn from the evolution of classical computing and begin to integrate quantum nodes, control fields, and classical logic. I'm interested in designing and demonstrating integrated, scalable architectures for building, maintaining, and controlling quantum systems. During my PhD I integrated diamond based quantum memories into a photonic integrated circuit and am interested in expanding this to leverage CMOS technology.
References:
1. Scalable integration of long-lived quantum memories into a photonic circuit Sara Mouradian, Tim Schroeder, Carl B. Poitras, Luozhou Li, Jordan Goldstein, Edward H. Chen, Michael Walsh, Jaime Cardenas, Matthew L. Markham, Daniel J. Twitchen, Michal Lipson, Dirk Englund, PRX, 5 (3), 031009 (2015)
2. A tunable waveguide-coupled cavity design for scalable interfaces to solid-state quantum emitters Sara Mouradian, Dirk Englund, APL Photonics, 2 (4), 046103 (2017)
Design and Fabrication of Diamond Nanophotonics
The NV center in diamond is an important tool for quantum information processing, and almost all applications directly depend on the rate of photons that can be collected from these centers. To increase the rate of emission and collection, it is necessary to pattern the diamond on the scale of the wavelengths of interest (100s of nm). We have developed a process to fabricate state-of-the-art nanophotonic structures from bulk diamond, demonstrating increased emission, collection, and routing control of photons emitted from NV centers in diamond.
References:
1. Rectangular Photonic Crystal Nanobeam Cavities in Bulk Diamond Sara Mouradian, Noel Wan, Tim Schroeder, Dirk Englund, Applied Physics Letters 111, 021103 (2017)
2. Two-Dimensional Photonic Crystal Slab Nanocavities on Bulk Single-Crystal Diamond Noel Wan, Sara Mouradian, Dirk Englund, Applied Physics Letters 112, 141102 (2018)
3. Fabrication of Triangular Nano Beam Waveguide Networks in Bulk Diamond Using Single-Crystal Silicon Hard Masks, Igal Bayn*, Sara Mouradian* , Luozhou Li, Tim Schroeder, Ophir Gaathon, Ming Lu, Aaron Stein, Dirk Englund, APL 105 (21), 211101 (2014)