Dual quadratic estimates in polynomial and boolean programming
Annals of Operations Research
Global Optimization with Polynomials and the Problem of Moments
SIAM Journal on Optimization
An Introduction to Quantum Filtering
SIAM Journal on Control and Optimization
Network Synthesis of Linear Dynamical Quantum Stochastic Systems
SIAM Journal on Control and Optimization
A Newton-like method for solving rank constrained linear matrix inequalities
Automatica (Journal of IFAC)
Brief paper: On the geometric and dynamic structures of the H2 optimal and H∞ central controllers
Automatica (Journal of IFAC)
Sliding mode control of two-level quantum systems
Automatica (Journal of IFAC)
Switching control of closed quantum systems via the Lyapunov method
Automatica (Journal of IFAC)
Time-varying H∞ control for a class of linear quantum systems: A dynamic game approach
Automatica (Journal of IFAC)
Notes on sliding mode control of two-level quantum systems
Automatica (Journal of IFAC)
Quantum control and information processing
Quantum Information Processing
Minimal resources identifiability and estimation of quantum channels
Quantum Information Processing
Hi-index | 22.16 |
Based on a recently developed notion of physical realizability for quantum linear stochastic systems, we formulate a quantum LQG optimal control problem for quantum linear stochastic systems where the controller itself may also be a quantum system and the plant output signal can be fully quantum. Such a control scheme is often referred to in the quantum control literature as ''coherent feedback control''. It distinguishes the present work from previous works on the quantum LQG problem where measurement is performed on the plant and the measurement signals are used as the input to a fully classical controller with no quantum degrees of freedom. The difference in our formulation is the presence of additional non-linear and linear constraints on the coefficients of the sought after controller, rendering the problem as a type of constrained controller design problem. Due to the presence of these constraints, our problem is inherently computationally hard and this also distinguishes it in an important way from the standard LQG problem. We propose a numerical procedure for solving this problem based on an alternating projections algorithm and, as an initial demonstration of the feasibility of this approach, we provide fully quantum controller design examples in which numerical solutions to the problem were successfully obtained. For comparison, we also consider the case of classical linear controllers that use direct or indirect measurements, and show that there exists a fully quantum linear controller which offers an improvement in performance over the classical ones.