Observation of V-type electromagnetically induced transparency and optical switch in cold Cs atoms by using nanofiber optical lattice

Optical nanofiber(ONF)is a special tool to achieve the interaction between light and matter with ultralow power.In this paper,we demonstrate V-type electromagnetically induced transparency(EIT)in cold atoms trapped by an ONFbased two-color optical lattice.At an optical depth of 7.35,90%transmission can be achieved by only 7.7 pW coupling power.The EIT peak and linewidth are investigated as a function of the coupling optical power.By modulating the pWlevel control beam of the ONF-EIT system in sequence,we further achieve efficient and high contrast control of the probe transmission,as well as its potential application in the field of quantum communication and quantum information science by using one-dimensional atomic chains.