Accession Number:

ADA470587

Title:

Small-Qubit-Number Methods for Superconductive Quantum Computation

Descriptive Note:

Final rept. 1 Apr 2004-31 Jul 2007

Corporate Author:

MASSACHUSETTS INST OF TECH CAMBRIDGE

Personal Author(s):

Report Date:

2007-06-30

Pagination or Media Count:

12.0

Abstract:

We have developed two experimental schemes that can be used to implement the Factorized Quantum Lattice-Gas Algorithm for the 1 D Diffusion Equation with Persistent-Current Qubits. One scheme involves biasing the PC Qubit at multiple flux bias points throughout the course of the algorithm. An implementation analogous to that done in Nuclear Magnetic Resonance Quantum Computing is also developed. Errors due to a few key approximations utilized and differences between the PC Qubit and NMR systems were studied Adiabatic quantum computation AQCis an approach to universal quantum computation in which the entire computation is performed in the ground state of a suitably chosen Hamiltonian. To make feasible a large-scale AQC experiment, we have proposed a scalable architecture for AQC based on the superconducting qubits. We have developed a set of processes that address the theoretically predicted need for extremely well-matched Josephson junction qubits in quantum computers. The work has focused on novel fabrication approaches such as nanoimprint lithography, which is able to replicate patterns with an extremely high degree of uniformity, and on methods of electron-beam lithography that achieve exceptional resist contrast, and thus high resolution, low line-edge roughness, and a correspondingly high degree of dimensional control in the resulting figures. We have accomplished this feat using two complimentary methods, one for negative-tone resist using cold development, the other for positive-tone resist using salt in the development solution. We have also demonstrated a method of AlAlOxAl junction fabrication that uses lithographically-defined reentrant resist profiles.

Subject Categories:

  • Electricity and Magnetism
  • Particle Accelerators
  • Quantum Theory and Relativity

Distribution Statement:

APPROVED FOR PUBLIC RELEASE