Abstract: Sense+compute (S+C) quantum-state carriers (QSCs), e.g., rubidium atoms, can be used provide more scalable quantum sensor systems. Multiple S+C QSCs can capture sensor data. The sensor data can then be transformed in the quantum domain according to a quantum tomographic protocol. The transformed data can be measured to provide a respective classical domain measurement. The sensing, transformation, and measurement can be repeated to provide a set of measurements (corresponding to different transformations) that can be combined according to the quantum tomography protocol to generate a model of the original quantum state. Estimation error associated with the model can be scaled down at a rate corresponding more closely to increases in the number N of QSCs than ?{square root over (N)}, even in the presence of noise.

Abstract: A device includes applying coupling and transformation operations to quantum states according to a Hamiltonian specification. Information is received at a digital computer based in part on measurements of the quantum states. The digital computer provides information for preparing quantum states associated with quantum processing elements based in part on the information. A control module applies coupling and transformation operations based on interaction with the digital computer for processing the constrained optimization problem. The processing includes preparing quantum states associated with quantum processing elements characterized by a summation of a constraint Hamiltonian and an objective Hamiltonian. The processing further includes operating the control module to evolve a time-dependent Hamiltonian by forming a sum of a first term having the constraint Hamiltonian and a second term.

Abstract: Sense+compute (S+C) quantum-state carriers (QSCs), e.g., rubidium atoms, can be used provide more scalable quantum sensor systems. Multiple S+C QSCs can capture sensor data. The sensor data can then be transformed in the quantum domain according to a quantum tomographic protocol. The transformed data can be measured to provide a respective classical domain measurement. The sensing, transformation, and measurement can be repeated to provide a set of measurements (corresponding to different transformations) that can be combined according to the quantum tomography protocol to generate a model of the original quantum state. Estimation error associated with the model can be scaled down at a rate corresponding more closely to increases in the number N of QSCs than ?{square root over (N)}, even in the presence of noise.

Abstract: A quantum-hardened power grid includes grid nodes (e.g., power plants, renewable energy sources and substations) and transmission lines connecting the grid nodes. The grid nodes include stable quantum clocks that permit the power grid to continue operation in the event of downtime for a GPS or other external synchronization reference. Operation sans an external reference can be extended by synchronizing atomic clocks across grid nodes using a quantum network. The atomic clocks can be used with quantum sensors and quantum computers to provide grid state estimates, e.g., using quantum tomography “at the edge”. In addition, these quantum devices can be used to compute responses to grid faults and cyberattacks.