Superposition of states in multi-lambda systems via generalized pulse area method

Abstract

This paper presents an exact analytic solution for creation of any preselected coherent superposition of states in multi-lambda quantum systems by a train of coincident pulses. We show that the solution of a multi-lambda system composed of degenerate ground states, excited states, and a single initial state can be reduced by using Morris–Shore transformation to the solution of a three-state system. In this method, all of the pump and Stokes pulses have the same time dependence and the ratio of the pump pulses can be used to control the probability amplitudes of the ground states in the coherent superposition of states. Effect of spontaneous emission is efficiently suppressed by employing a train of coincident pulses. This technique resembles the technique of generalized -pulses with minimal pulse areas which is easy to reach experimentally.

Keywords:

• pulse area method
• Morris–Shore transformation
• multi-lambda systems

Notes

We acknowledge the financial support of the MSRT of Iran and Urmia University.