Coherent has released an infrared version of the company's successful Verdi family of solid state lasers, delivering 25W of single-mode continuous wave (CW) output at 1064nm. The new Verdi IR 25 laser has the same diode-pumped, solid-state (Nd:YVO4) unidirectional ring-resonator design as is standard in all green Verdi lasers. Its single-longitudinal-mode output has noise of less than 0.04 per cent RMS, narrow-linewidth of less than 2.5MHz FWHM, and a coherence length greater than 60m. In addition, a piezo-actuated resonator mirror enables the output frequency to be tuned over a range of more than 3.2GHz, and/or to be locked to an external reference cavity. The bandwidth for piezoelectric control is DC to 20kHz.
Outstanding beam-pointing stability (more than 2µrad/°C) and beam quality (M² less than 1.1) eliminate the need for frequent adjustments of the beam and simplify laser alignment. Moreover, the natural stability of this single-mode design means that the output power can be smoothly varied over a 15W to 25W range without mode-hops. No other CW infrared laser offers this combination of power and stability. In addition, the output is linearly polarised with an extinction ratio greater than 100:1.
The Verdi IR 25 is suitable for applications in the optical trapping of atoms, where its low noise and mode-hop-free operation enables atom trapping for extended times. The high output power means a single Verdi IR laser can generate several traps simultaneously. Other applications include optical tweezers, optical/semiconductor material development and remote optical sensing. In addition, the low noise and high power make the Verdi IR 25 an ideal source for harmonic generation and pumping mid-infrared optical parametric oscillators (OPOs) for high-resolution molecular spectroscopy.