PhD Proposal: Fernando Calderon
Tuesday, May 6, 2014 · 10 AM - 12 PM
TITLE: Dynamically Corrected Gates for Capacitively Coupled Singlet-Triplet Qubits
ABSTRACT: Among the different candidates for a quantum computer, spin qubits in semiconductor quantum dots present the advantages of scalability, long coherence times and rapid gate operations. Particularly, a qubit encoded in the low-lying singlet-triplet subspace of two electrons in a double-dot has the promising features of immunity to homogeneous fluctuations of the magnetic field and purely electrical controllability. Nevertheless, the major drawback for the realization of a quantum computer is qubit decoherence due to environmental noise. Singlet-triplet qubits are affected by two sources of noise: charge noise and Overhauser noise. In this light, dynamically corrected gates (DCGs) were proposed to protect qubit operations from errors. A type of DCGs, customized under the particular constraints of the double-dot system, has recently been proposed to correct errors in single-qubit and exchange-based two-qubit operations.
So far, there is not an approach to DCGs for capacitive-based two-qubit gates and considering the advantages (scalability and no leakage states) of the capacitive coupling scheme over the exchange coupling scheme, the present research proposal has as its objective the design of dynamically corrected gates for two capacitively coupled singlet-triplet qubits.