ABSTRACT
There is equal “wonder” looking back from this end of the time tunnel that Feynman was able to herald the promise of quantum technology somany years ago. In our quest for a deeper understanding of physical and biological phenomena, only now, perhaps, we move seriously into the control of the “small-scale” world of quantum mechanics. The rules of this world herald new types of materials and devices [1-3]. Quantum information systems and instruments of measurement promise an exponential improvement in speed and/or resolution compared to their classical counterparts. Many of these systems inherently rely on estimation and control for their normal operation, for example, atomic clocks, measuring electrical, thermal, and photonic characteristics, biometrics, magnetometry, gravimetry, and the many proposed implementations of a quantum computer. Instrumentation noise, decoherence, and modeling errors are all sources of uncertainty which either separately or in combination hinder the ability of the material or device to meet performance demands. Some of these systems require estimation to determine if the system is meeting performance demands and then apply a control adapted to the specific estimated error, for example [4-8].
