Hassaun A. Jones-Bey

Senior Editor and Freelance Writer

Hassaun A. Jones-Bey was a senior editor and then freelance writer for Laser Focus World.

Research

NANOTECHNOLOGY: Photonic crystal aids quest for visible plasmon laser

March 1, 2009
Researchers from the New Jersey Institute of Technology (NJIT; Newark, NJ) have reported the first demonstration of laser threshold, gain, spectral line-narrowing, and feedback...
Sunlight (not shown) enters the top surface of a luminescent solar concentrator (LSC) and stimulates emission of luminescent rays that either proceed, through total internal reflection, to the solar cell (at left of each drawing) or exit the concentrator if they fall within the escape cone (top). When mirrors are applied directly to bottom and edges (blue), total internal reflection ceases, and all rays reflect with the reflection coefficient of the mirror, which leads to a reduction in reflection and power-conversion efficiency for rays outside of the escape cone (bottom left). An air gap between the mirror and the LSC, however, enhances efficiency by combining total internal reflection with mirror reflection of escaping rays (bottom right) [1].
Sunlight (not shown) enters the top surface of a luminescent solar concentrator (LSC) and stimulates emission of luminescent rays that either proceed, through total internal reflection, to the solar cell (at left of each drawing) or exit the concentrator if they fall within the escape cone (top). When mirrors are applied directly to bottom and edges (blue), total internal reflection ceases, and all rays reflect with the reflection coefficient of the mirror, which leads to a reduction in reflection and power-conversion efficiency for rays outside of the escape cone (bottom left). An air gap between the mirror and the LSC, however, enhances efficiency by combining total internal reflection with mirror reflection of escaping rays (bottom right) [1].
Sunlight (not shown) enters the top surface of a luminescent solar concentrator (LSC) and stimulates emission of luminescent rays that either proceed, through total internal reflection, to the solar cell (at left of each drawing) or exit the concentrator if they fall within the escape cone (top). When mirrors are applied directly to bottom and edges (blue), total internal reflection ceases, and all rays reflect with the reflection coefficient of the mirror, which leads to a reduction in reflection and power-conversion efficiency for rays outside of the escape cone (bottom left). An air gap between the mirror and the LSC, however, enhances efficiency by combining total internal reflection with mirror reflection of escaping rays (bottom right) [1].
Sunlight (not shown) enters the top surface of a luminescent solar concentrator (LSC) and stimulates emission of luminescent rays that either proceed, through total internal reflection, to the solar cell (at left of each drawing) or exit the concentrator if they fall within the escape cone (top). When mirrors are applied directly to bottom and edges (blue), total internal reflection ceases, and all rays reflect with the reflection coefficient of the mirror, which leads to a reduction in reflection and power-conversion efficiency for rays outside of the escape cone (bottom left). An air gap between the mirror and the LSC, however, enhances efficiency by combining total internal reflection with mirror reflection of escaping rays (bottom right) [1].
Sunlight (not shown) enters the top surface of a luminescent solar concentrator (LSC) and stimulates emission of luminescent rays that either proceed, through total internal reflection, to the solar cell (at left of each drawing) or exit the concentrator if they fall within the escape cone (top). When mirrors are applied directly to bottom and edges (blue), total internal reflection ceases, and all rays reflect with the reflection coefficient of the mirror, which leads to a reduction in reflection and power-conversion efficiency for rays outside of the escape cone (bottom left). An air gap between the mirror and the LSC, however, enhances efficiency by combining total internal reflection with mirror reflection of escaping rays (bottom right) [1].
Optics

PHOTOVOLTAICS: Optical modeling determines luminescent solar-concentrator efficiency

A multi-institutional team of researchers, working through the FULLSPECTRUM project of the European Commission, has published encouraging research results from a five-year investigation...
(Courtesy of Harvey Mudd College and Los Alamos National Laboratory)
An optical refrigerator depends on removal of high-energy photons to cool a special laser-pumped material. In the simplest implementation, this is accomplished by directly attaching a thermal link that is then butt-coupled to a heat load (top). To improve refrigeration efficiency, several versions of optical-waveguide tapers and lens elements can be used as thermal links to remove absorptive photons (bottom).
An optical refrigerator depends on removal of high-energy photons to cool a special laser-pumped material. In the simplest implementation, this is accomplished by directly attaching a thermal link that is then butt-coupled to a heat load (top). To improve refrigeration efficiency, several versions of optical-waveguide tapers and lens elements can be used as thermal links to remove absorptive photons (bottom).
An optical refrigerator depends on removal of high-energy photons to cool a special laser-pumped material. In the simplest implementation, this is accomplished by directly attaching a thermal link that is then butt-coupled to a heat load (top). To improve refrigeration efficiency, several versions of optical-waveguide tapers and lens elements can be used as thermal links to remove absorptive photons (bottom).
An optical refrigerator depends on removal of high-energy photons to cool a special laser-pumped material. In the simplest implementation, this is accomplished by directly attaching a thermal link that is then butt-coupled to a heat load (top). To improve refrigeration efficiency, several versions of optical-waveguide tapers and lens elements can be used as thermal links to remove absorptive photons (bottom).
An optical refrigerator depends on removal of high-energy photons to cool a special laser-pumped material. In the simplest implementation, this is accomplished by directly attaching a thermal link that is then butt-coupled to a heat load (top). To improve refrigeration efficiency, several versions of optical-waveguide tapers and lens elements can be used as thermal links to remove absorptive photons (bottom).
Research

SOLID-STATE LASERS: CVD growth methods enable diamond Raman laser

The lure of compact solid-state diamond lasers operating in desirable spectral regions and power regimes, along with numerous other optoelectronic applications, is helping to ...