Optimal quantum control via numerical pulse shape optimization for two exciton qubits confined to semiconductor quantum dots

Optimal quantum control (OQC), which iteratively optimizes the control Hamiltonian to achieve a target quantum state, is a versatile approach for manipulating quantum systems. For optically-active transitions, OQC can be implemented using femtosecond pulse shaping which provides control over the amplitude and/or phase of the electric field. Optical pulse shaping has been employed to optimize physical processes such as nonlinear optical signals [1], photosynthesis [2], and has recently been applied to optimizing single-qubit gates in multiple semiconductor quantum dots [3]. In this work, we examine the use of numerical pulse shape optimization for optimal quantum control of multiple qubits confined to quantum dots as a function of their electronic structure parameters. The numerically optimized pulse shapes were found to produce high fidelity quantum gates for a range of transition frequencies, dipole moments, and arbitrary initial and final states. This work enhances the potential for scalability by reducing the laser resources required to control multiple qubits.\\[4pt] [1] Bartels, R. et al., Nature 2000, 406, 164-166.\\[0pt] [2] Herek, J. L. et al., Nature 2002, 417, 533-535.\\[0pt] [3] Gamouras, A. et al; Nano Lett. 2013, 13(10), 4666-4670.