Anomalous discharge mode in a kinetically-enhanced copper vapor laser: visualization by "Hook" method

An anomalous discharge mode of a kinetically-enhanced copper vapor laser is reported. Under conditions of high-HCl density, the discharge makes an abrupt transition into a mode which is identified by a near field laser beam profile having a green (511 nm) central spot on a yellow (578 nm) background. Hook-method measurements reveal that a steep channel is produced in the radial Cu density profile, which forms a strong plasma lens duct for wavelengths nearby Cu resonance.