Ho:YLF pumped HBr laser

Abstract

A Ho:YLF laser pumped HBr molecular laser was developed that produced up to 2.5 mJ of energy in the 4 micron wavelength region. The Ho:YLF laser was fiber pumped using a commercial Tm:fibre laser. The Ho:YLF laser was operated in a single longitudinal mode via injection seeding with a narrow band diode laser which in turn was locked to one of the HBr transitions. The behavior of the HBr laser was described using a rate equation mathematical model and this was solved numerically. Good agreement both qualitatively and quantitatively between the model and experimental results was obtained.

Optically pumped tunable HBr laser in the mid-infrared region

“…The highest reported output energy from such a laser thus far was 2.5 mJ in a 132 ns pulse, which emitted simultaneously on the P(4) and P(5) lines (the energy level diagram is shown in Fig. 1), and this result was previously reported by our group [6]. An in-house developed injection seeded single-frequency Ho:YLF ring laser was used as the pump source [7].…”

Ho:YLF & Ho:LuLF slab amplifier system delivering 200 mJ, 2 µm single-frequency pulses

“…High energy, single-frequency sources at 2 µm are sought after for remote sensing of CO 2 [1] as well as for pumping of molecular lasers [2]. Excellent sources of 2 µm radiation are lasers built with Thulium (Tm 3+ or just Tm) and Holmium (Ho 3+ or just Ho) doped materials which oscillate in the region of 1.9 µm and 2 µm respectively.…”

2-μm high-power multiple-frequency single-mode Q-switched Ho:YLF laser for DIAL application

“…First single-frequency injection-seeding operation of a Ho:YLF oscillator was already mentioned at low PRF (100 Hz) in Botha et al [19] at 2,064 nm but not fully characterized. Here, the seeding of the Ho:YLF oscillator is tested at high PRF (2 kHz) and the DFB seeder is locked to R30 CO 2 line center at 2,050.97 nm.…”

“…A precursor work of Bollig et al [18,19] demonstrated an injection-seeded single-frequency Q-switched Ho:YLF master oscillator power amplifier (MOPA) pumped by a Tm fiber laser which delivers 70 mJ per pulse at 50 Hz repetition rate at 2,064 nm. Seeding was performed using an internal-modulated distributed-feedback laser diode (DFB) with a Pound-Drever-Hall (PDH) technique to lock the oscillator cavity length [20].…”