2014 A tunable single mode laser has been used to excite the 03BB = 640.2 and 626.6 nm lines of 20Ne, 21Ne and 22Ne. Using the velocity selective optical pumping method, we have measured the hyperfine structures and isotopic shifts of these two lines. We obtain the following values for the 21Ne hyperfine structure constants of the 2p9 level : We have also measured isotope shifts and obtained va...

When stimulated Raman pumping (SRP) is applied to a stream of isolated molecules, such as found in a supersonic molecular beam expansion, we show that SRP can neither saturate nor power broaden a molecular transition connecting two metastable levels that is resonant with the energy difference between the pump and Stokes laser pulses. Using the optical Bloch-Feynman equations, we discuss the pum...

The gapless energy spectrum of electrons and holes in single graphene layers (SGLs), graphene bilayers (GBLs), and non-Bernal stacked multiple graphene layers (MGLs) opens up prospects of creating graphene-based terahertz (THz) and infrared (IR) lasers. The interband population inversion in such lasers can be achieved, for instance, by optical pumping [1]. However, the excess energy received by...

We report the successful application of space-charge forces of a low-energy electron beam for improvement of particle lifetime determined by beam-beam interaction at a high-energy collider. In our experiments, an electron lens, a novel instrument developed for the beam-beam compensation, was set on a 980-GeV proton bunch at the Fermilab Tevatron proton-antiproton collider. The proton-bunch loss...

Along with its well known charge and mass, the electron also carries an intrinsic angular momentum, or spin. The rules of quantum mechanics allow us to measure only the probability that the electron spin is in one of two allowed spin states. When a beam carries a net excess of electrons in one of these two allowed spin states, the beam is said to be polarized. The beam polarization may be measu...

We present modeling studies of quasi-three-level laser oscillators, the validity of which was revealed by Ti:Al(2)O(3)-pumped Yb:YAG laser experiments, and these results are shown to be in excellent agreement with the theory. As much as 75% slope efficiency was obtained with a hemispherical laser cavity. Previous modeling calculations of laser performance have been valid only for certain specia...