Efficient cryogenic near-infrared Tm:YLF laser

Efficient cryogenic near-infrared Tm:YLF laser.

Operation of a cw thulium laser emitting at 816 nm has been demonstrated in bulk Tm:YLF with 46% slope efficiency. Prior cw demonstrations of this transition have been limited to ZBLAN fiber hosts and prior lasing in bulk crystalline host material has been limited to quasi-cw operation due to population trapping. Trapping at the 3F4 level was mitigated by co-lasing at 1876 nm. The co-lasing tec...

Near-Infrared Laser Adjuvant for Influenza Vaccine

Safe and effective immunologic adjuvants are often essential for vaccines. However, the choice of adjuvant for licensed vaccines is limited, especially for those that are administered intradermally. We show that non-tissue damaging, near-infrared (NIR) laser light given in short exposures to small areas of skin, without the use of additional chemical or biological agents, significantly increase...

Near-infrared diode laser airborne hygrometer

We describe a new laser-based hygrometer for ambient water vapor monitoring which uses a fiber-optic coupled, near-infrared diode laser in conjunction with high frequency wavelength modulation spectroscopy. The instrument operates unattended, uses little power, can be extremely compact, and exhibits high detection sensitivity. This instrument was flown on a KC-135 aircraft for a period of six m...

Infrared Filters for Cryogenic Receivers

A cryogenic infrared calibration target.

A compact cryogenic calibration target is presented that has a peak diffuse reflectance, R ⩽ 0.003, from 800 to 4800 cm(-1) (12 - 2 μm). Upon expanding the spectral range under consideration to 400-10,000 cm(-1) (25 - 1 μm) the observed performance gracefully degrades to R ⩽ 0.02 at the band edges. In the implementation described, a high-thermal-conductivity metallic substrate is textured with ...