Efficient infrared upconversion via a ladder-type atomic configuration

Efficient infrared imaging upconversion via quantum coherence

We show that quantum coherence can be used to achieve marked improvement in the efficiency of the process of infrared upconversion. In one particular example which we analyze in detail, we show that it is possible to convert infrared radiation at a wavelength of 100 mm to the visible with essentially 100% efficiency while maintaining diffraction-limited imaging of the infrared field. © 2000 Ame...

Efficient infrared upconversion in Gap

Mechanisms for linear conversion of infrared to visible were investigated in extrinsic Gap. Efficient (1 %) conversion of 10 micron to visible was observed in GaP:Zn,O. Several device applications are discussed and a quantum counter scheme involving 111-V photocathodes is presented.

Near-infrared deep brain stimulation via upconversion nanoparticle-mediated optogenetics.

Optogenetics has revolutionized the experimental interrogation of neural circuits and holds promise for the treatment of neurological disorders. It is limited, however, because visible light cannot penetrate deep inside brain tissue. Upconversion nanoparticles (UCNPs) absorb tissue-penetrating near-infrared (NIR) light and emit wavelength-specific visible light. Here, we demonstrate that molecu...

Mid-infrared upconversion spectroscopy

Relationship between two- and three-photon coherence in a ladder-type atomic system.

We investigated the relationship between two- and three-photon coherence in terms of the transition routes and coupling field intensities in a Doppler-broadened ladder-type atomic system for the 5S(1/2)-5P(3/2)-5D(5/2) transition in (87)Rb atoms. Three-photon electromagnetically induced absorption (TPEIA) due to three-photon coherence was observed in the only transition route that exhibited a d...