Decoherence dynamics of a charge qubit coupled to the noise bath

By virtue of the canonical quantization method, we present a quantization scheme about a charge qubit based on the superconducting quantum interference device (SQUID), taking the self-inductance of the loop into account. Under the reasonable short-time approximation, we study the effect of decoherence in the Ohmic case by employing the response function and the norm. It is confirmed that the decoherence time which depends on the parameters of circuit components, coupling strength, and temperature, can be as low as several picoseconds, so that there is enough time to record information.