Learning to Control Quantum Systems

Haixu Yu, Xudong Xu, Hailan Ma +2 more

In recent years, some experimental studies and simulations show that reinforcement learning (RL) is an effective learning control approach for solving certain quantum control problems. In this paper, Q-learning with different exploration strategies (e.g., ε-greedy and Softmax), probabilistic Q-learning (PQL) and quantum reinforcement learning (QRL) are applied to solve the state transition problem of two-level quantum systems (e.g., spin-1/2 systems), respectively. These reinforcement learning algorithms are introduced and analyzed regarding the learning control problem of the spin-1/2 system. According to the constraints of the control fields, two typical kinds of controllers, i.e., three-switch controller and Bang-Bang controller, are designed using reinforcement learning. The learning performance of the above RL algorithms for both of the three-switch control and Bang-Bang control of two-level quantum systems are demonstrated and analyzed.

G. Huang

Daoyi Dong, Ian R. Petersen

Hailan Ma, Chunlin Chen

This paper summarizes several recent achievements in the area of learning control of quantum systems and draw several new directions for future research. Three learning algorithms including gradient method, differential evolution and reinforcement learning are introduced for quantum control. Quantum state control in closed and open quantum systems is analyzed, where gradient method and differential evolution are employed, respectively. The approach of deep reinforcement learning for quantum gate control is introduced, and a sampling-based learning control is illustrated for robust control of quantum gates.

Daoyi Dong, Ian R. Petersen

This chapter presents results on enhancing robustness of quantum systems with uncertainties using the sampling-based learning control (SLC) method. In Sect. 4.2, the SLCSampling-based learning control method is applied to state control of superconducting qubitsQubit, robust control of photoassociationPhotoassociation of O+H and synchronizing a laser with molecules for charge transfer $$^\text {a}$$ , $$^\text {b}$$ , $$^\text {c}$$ . Robust control based on SLC and b-GRAPE is presented for generating quantum gatesQuantum gate in Sect. 4.3 and SLC of open quantum systems is investigated in Sect. 4.4 $$^\text {d}$$ .

J. W. Clark, Dennis G. Lucarelli, Tzyh‐Jong Tarn