Quantum Information in Semiconductors: Noiseless Encoding in a   Quantum-Dot Array
  A potential implementation of quantum-computation schemes in semiconductor-based structures is proposed. In particular, an array of quantum dots is shown to be an ideal quantum register for a noiseless information encoding. In addition to the suppression of phase-breaking processes in quantum dots due to the well-known phonon bottleneck, we show that a proper quantum encoding allows to realise a decoherence-free evolution on a time-scale long compared to the femtosecond scale of modern ultrafast laser technology. This result might open the way to the realization of semiconductor-based quantum processors. 
Paolo Zanardi (1 and 2) and Fausto Rossi (1 and 3) ((1) Istituto   Nazionale per la Fisica della Materia (INFM) (2) Institut...