Prof Jonathan Jones

Abstract:

Generic models of two and three coupled two-level system (TLS) entangled through their interaction with a single mode field sustained in an ideal cavity, including other interactions among TLS, exhibit violation of Bell's and Mermin's inequality periodically in the interaction time of theTLS with the field mode. The effect of the initial states of TLS on the violation of these inequalities are discussed. The entanglement measure in terms of concurrence for these systems is also calculated which matches very well with the violation of Bell's inequality results. These systems can be employed for quantum logic gate implementations useful in quantum computing. © 2012 Old City Publishing, Inc.

Abstract:

We briefly describe the use of gradient ascent pulse engineering (GRAPE) pulses to implement quantum logic gates in nuclear magnetic resonance quantum computers, and discuss a range of simple extensions to the core technique. We then consider a range of difficulties that can arise in practical implementations of GRAPE sequences, reflecting non-idealities in the experimental systems used.

Abstract:

We use the mode-matching technique to study parallel-plate waveguide resonant cavities that are filled with a dielectric. We apply the generalized scattering matrix theory to calculate the power transmission through the waveguide-cavities. We compare the analytical results to experimental data to confirm the validity of this approach.