Energy barrier to decoherence - art. no. 040302

We propose a ground-state approach to realizing quantum computers. This sch eme is time-independent and inherently defends against decoherence by posse ssing an energy barrier to excitation. We prove that our time-independent q ubits can perform the same algorithms as their time-dependent counterparts. Advantages and disadvantages of the time-independent approach are describe d. A model involving quantum dots is provided for illustration.