Bayat, AbolfazlCreffield, CharlesJefferson, John HPepper, MichaelBose, Sougato2023-06-182023-06-182015-100268-124210.1088/0268-1242/30/10/105025https://hdl.handle.net/20.500.14352/24284©IOP Publishing Ltd. AB was supported by the EPSRC grant EP/K004077/1 (nano-electronic based quantum technologies). SB is supported by an ERC grant. CEC was supported by the MINECO (Spain) through grants FIS2010-21372 and FIS2013-41716-P. MP thanks the EPSRC, and JHJ and CEC acknowledge support from the EU NanoCTM network.We show how single quantum dots, each hosting a singlet-triplet qubit, can be placed in arrays to build a spin quantum cellular automaton. A fast (∼ 10 ns) deterministic coherent singlet- triplet filtering, as opposed to current incoherent tunneling/slow-adiabatic based quantum gates (operation time ∼ 300 ns), can be employed to produce a two-qubit gate through capacitive (electrostatic) couplings that can operate over significant distances. This is the coherent version of the widely discussed charge and nano-magnet cellular automata, and would increase speed, reduce dissipation, and perform quantum computation while interfacing smoothly with its classical counterpart. This combines the best of two worlds – the coherence of spin pairs known from quantum technologies, and the strength and range of electrostatic couplings from the charge-based classical cellular automata. Significantly our system has zero electric dipole moment during the whole operation process, thereby increasing its charge dephasing time.engjournal articlehttp://dx.doi.org/10.1088/0268-1242/30/10/105025http://iopscience.iop.orghttp://arxiv.org/abs/1310.4376open access51-73ComputationFieldFísica-Modelos matemáticosFísica matemática