STIRAP in sodium vapor with picosecond laser pulses

TL;DR

This study investigates STIRAP transfer efficiency in sodium vapor using picosecond laser pulses, revealing quantum interference effects between multiple pathways and demonstrating near Fourier transform-limited laser performance.

Contribution

It provides experimental and theoretical insights into multi-pathway quantum interference in STIRAP with ultrafast pulses in sodium vapor.

Findings

Both 3p states influence transfer efficiency when tuned to the 3P1/2 state.

Quantum interference occurs between competing pathways.

High-efficiency transfer achieved with near-transform-limited pulses.

Abstract

Experimental measurements and calculations of STIRAP transfer efficiencies were made on a sodium gas starting from the $3^2{\rm S}_{1/2}$ electronic ground state, passing through the $3^2{\rm P}_{1/2}$ and/or the $3^2{\rm P}_{3/2}$ to the $5^2{\rm S}_{1/2}$ state. The lasers used in the experiments had a pulse width of several picoseconds and were close to the Fourier transform limit. Although the linewidth of the laser was much smaller than the spin orbit splitting between the $3^2{\rm P}_{1/2}$ and $3^2{\rm P}_{3/2}$ states, Experiments and calculations reveal that both 3p states play a role in the transfer efficiency when the lasers are tuned to resonance through the $3^2{\rm P}_{1/2}$ state, revealing evidence for quantum interference between the competing pathways.