The Center for Quantum Devices in the News by    
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81.  
QCL peak power record smashed
QCL peak power record smashed
Photonics Spectra magazine, February 2010, p. 19-20 - February 28, 2010
Only a year ago, the peak output power of a quantum cascade laser (QCL) was only 34W. Today, thanks to research at the Center for Quantum Devices (CQD), peak power of 120 W from a single device at room temperature has been achieved. This "breakthrough is particularly attractive for sensing chemicals at a distance and for infrared countermeasures," Professor Razeghi said, "because power is a luxury that defines range, speed, and sensitivity for targeting remote applications." ... [read more]
 
82.  
Producing more light than heat from quantum cascade lasers
Producing more light than heat from quantum cascade lasers
Semiconductor Today magazine, Vol. 5, Issue 1 - February 28, 2010
Two separate groups have reported increased wall-plug efficiency (WPE) for quantum cascade lasrs (QCLs) in Nature Phtonics: Manijeh Razeghi et. al at the Center for Quantum Devices (CQD) and Peter Liu et. al from Princeton and John Hopkins Universities. The CQD team uses a single-well injector to achieve 53% WPE at 40K with an emitting wavelength of 5 μm. In other words, they "Produce a quantum cascade laser that prduces more light than heat." ... [read more]
 
83.  
Quantum Cascade lasers, a glass half full
Quantum Cascade lasers, a glass half full
NATURE PHOTONICS | NEWS AND VIEWS - February 15, 2010
Since the first report of its successful operation in the mid-1990s1, the quantum cascade laser (QCL) has evolved to become an important source of mid-infrared and terahertz radiation. However, it has historically been labelled as a device with a relatively poor efficiency of operation. This view may finally be about to change, thanks to the report in Nature Photonics by the Center for Quantum Devices of mid-infrared QCLs that provide wall-plug efficiencies reaching 50% for the first time. ... [read more]
 
84.  
New Quantum Cascade Lasers Emit More Light Than Heat
New Quantum Cascade Lasers Emit More Light Than Heat
Northwestern University McCormick News Article - January 11, 2010
Northwestern University researchers have developed compact, mid-infrared laser diodes that generate more light than heat — a breakthroughs in quantum cascade laser efficiency. The results are an important step toward use of quantum cascade lasers in a variety of applications, including remote sensing of hazardous chemicals. The quantum cascade laser (QCL) is a diode laser that is designed on the quantum mechanical level to produce light at the desired wavelength with high efficiency. Unlike traditional diode lasers, the device is unipolar, requiring only electrons to operate. A significant effort has been spent trying to understand and optimize the electron transport, which would allow researchers to improve the laser quality and efficiency. “This breakthrough is significant because, for the very first time, we are able to create diodes that produce more light than heat,” says Razeghi. “Passing the 50 percent mark in efficiency is a major milestone, and we continue to work to optimize the efficiency of these unique devices.” ... [read more]
 
85.  
CQD Students Receives 1<sup>st</sup> and 2<sup>nd</sup> Place Boeing Engineering Award
CQD Students Receives 1st and 2nd Place Boeing Engineering Award
Boeing press release - December 2, 2009
Can Bayram, a fifth-year PhD student in electrical engineering and computer science and member of the Center for Quantum Devices, was selected as the Boeing Company’s 2009 Engineering Student of the Year. Pierre Yves-Delaunay, another 5th year PhD student also from the Center for Quantum Devices was the runner-up. ... [read more]
 
86.  
Researchers Demonstrate 100-Watt-Level Mid-infrared Lasers
Researchers Demonstrate 100-Watt-Level Mid-infrared Lasers
Northwestern University Press Release - December 1, 2009
Northwestern University researchers from the Center for Quantum Devices have achieved a breakthrough in quantum cascade laser (QCL) output power, delivering 120 watts from a single device at room temperature. In this work, Professor Razeghi’s team demonstrated that the ridge width of a broad-area QCL can be increased up to 400 microns, without suffering from filiamentation. As a result, room temperature peak output power as high as 120 watts was obtained from a single device, which is up from 34 watts only a year ago. ... [read more]
 
87.  
University Labs: Where Women Excel
University Labs: Where Women Excel
Society of Women Engineers Fall Magazine, Vol. 55, No. 4, p. 48-53 - September 30, 2009
What propels women to head university labs, especially when tenure and biological calendars collide? Manijeh Razeghi director of the Center for Quantum Devices at Northwestern University, stands in the its midst. She had the unique opportunity to build her center from the ground up. In her words, her goal was "to decrease the gap between research and production, while facing all the technical challenges and stringent requirements in order to ensure a safe and invigorating working environment." ... [read more]
 
88.  
ULTRAVIOLET DETECTORS: Nitrides push performance of UV photodiodes
ULTRAVIOLET DETECTORS: Nitrides push performance of UV photodiodes
Laser Focus World, p. 47-51 - September 1, 2009
Nitrides offer considerable advantages over other materials for ultraviolet detection. Recently, they proved useful for creating the world’s first UV single-photon detectors with efficiencies to 20%–detectors that could enable quantum computing and data encryption. ... [read more]
 
89.  
ULTRAVIOLET DETECTORS: Nitrides push performance of UV photodiodes
ULTRAVIOLET DETECTORS: Nitrides push performance of UV photodiodes
OptoIQ (A subsidiary of Laser Focus World) - September 1, 2009
Nitrides offer considerable advantages over other materials for ultraviolet detection. Recently, they proved useful for creating the world’s first UV single-photon detectors with efficiencies to 20%–detectors that could enable quantum computing and data encryption. ... [read more]
 
90.  
Superlattices see in the dark
Superlattices see in the dark
SPIE Newsroom - July 28, 2009
Six years ago, the Center for Quantum Devices (CQD) at Northwestern University fabricated the first IR camera based on Type-II material. After that, the CQD focused on improving the optical and electrical performance of the imager. We developed a new variant of a type-II superlattice, called M-structure, because of the M-shape of the band alignment, which allows for more-flexible control of the energy gap, energy levels, and effective mass. Many processing imporovements were also developed. The design, fabrication, and processes improvments have combined to make type-II superlattices a viable alternative to HgCdTe for IR imaging. ... [read more]
 

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