The research done by the graduate students on this grant focus on two topics: predominately, the focus was on the measurements of a persistent-current qubit driven by an on-chip radiation source, and secondarily on the fabrication of qubits for a fast turn around time. For the first topic the student preformed experiments of the monolithic integration of an onchip radiation source with a persistent-current (PC) qubit and dc SQUID measurement ...
The results of this research centered on the experimental studies of a single superconducting persistent current qubit, the implementation of type-II algorithms using these qubits, and the proposal for adiabatic quantum computing using these qubits. The major experimental results on single superconducting persistent current qubits have been the observation of the quantum energy level crossings in niobium qubits, and the microwave measurements of intra-well relaxation times. We have developed two ...
Two dilution refrigerators have been installed and made operational for the purpose of having dedicated measurement systems one at MIT and the other at the University of Rochester for carrying out quantum computing experiments. Both systems are a Kelvinox 400 model from Oxford instruments, equipped with both dc and rf lines for measurements; and both systems are vibrationally isolated and magnetically and electrically shielded for low noise measurements. Within the ...
The DC characteristics of single triangular Josephson Junction (JJ) cells and single row arrays have been studied to their potential as rf oscillators. Measurements of under damped systems reveal two steps in the current voltage (IV) characteristic, corresponding to LSC and LJ resonances. These steps are characteristics of single cells, and their position does not change significantly with array size. Measurements of two different cell sizes showed that the upper ...
A Josephson oscillator array was investigated through both DC and AC experiments. The simulations and analysis of Yukon and Lin suggested that arrays with three junctions per cell might have unique advantages as high frequency oscillators. These triangular arrays operate with a bias flux of half a flux quantum and power is coupled from the horizontal junctions. This configuration allows one to couple from a whole ...
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