Reduced dynamics with renormalization in solid-state charge qubit measurement

Quantum measurement will inevitably cause backaction on the measured system, resulting in the well-known dephasing and relaxation. In this paper, in the context of solid-state qubit measurement by a mesoscopic detector, we show that an alternative backaction known as renormalization is important under some circumstances. This effect is largely overlooked in the theory of quantum measurement.

Hong Kong SAR Government 604007 604508National Natural Science Foundation 60425412 90503013Major State Basic Research Project of China 2006CB921201 This work is supported by RGC (604007 and 604508) of the Hong Kong SAR Government the National Natural Science Foundation (60425412 and 90503013) and the Major State Basic Research Project (2006CB921201) of China.