## Sirui Lu - Research Overview
## Many-body physics, tensor network, and topological phasesWe derived neural network representations for many quantum many-body states, such as (generalized) stabilizer states, and topological ordered states. We expect our exact representation results will inspire future numerical studies for larger system sizes.
## Quantum algorithms on near-term devicesTwo candidates for noisy intermediate quantum technologies are quantum machine learning algorithms and quantum approximate optimization algorithm (QAOA). For QML, I did a numerical simulation for a generative quantum machine learning model and proposed a variational learning algorithm. For QAOA, the two most important open questions are its circuit depth scaling of intermediate depth and its diabatic mechanism. I address the first question with Murphy Yuezhen Niu and Prof. Isaac Chuang and the second question with Sheng-Tao Wang on diabatic annealing.
## Quantum entanglement
## Quantum simulation on AMO platforms.I have collaborated with many experimentalists in simulating quantum physics and benchmarking quantum devices on NMR and NV center systems. Collaborations on diﬀerent experiments platform deepen my understanding of the strength and limitations of diﬀerent systems. This, in turn, will help me to better work on theories with relevance to state-of-the-art experiments.
Together with my collaborators in Prof. Bei Zeng’s group, we develope the first NMR cloud quantum computing platform: NMRCloudQ.
We proposed a machine learning based method for the local quantum state tomography, which may be scalable to a large number of qubits.
## Quantum error correction and fault-toleranceIn this work, we construct quantum codes that allow transmitting both quantum and classical information with better parameters than hybrid codes obtained from the best-known stabilizer quantum codes. Our code construction is based on the codeword-stabilized code, which is the most general framework for constructing codes beyond stabilizer formalisms. This work elicited my interesting in non-stabilizer codes.
Since then, I became particularly interested in understanding how non-stabilizer codes could attribute to the realization of large-scale quantum computation. Examples abound: non-additive codes with a higher rate, topologically ordered system such as double semion and double Fibonacci, many fault-tolerant techniques involving the code deformation, code-switching, gauge fixing, and “loosely” versions of transversal gates. I am also interested in studying different physics from the quantum error correction perspective — for example, topological order and the black hole. |