|Author||Wienold, M. ♦ Röben, B. ♦ Lü, X. ♦ Rozas, G. ♦ Schrottke, L. ♦ Biermann, K. ♦ Grahn, H. T.|
|Source||United States Department of Energy Office of Scientific and Technical Information|
|Subject Keyword||CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS ♦ DESIGN ♦ ELECTRONS ♦ EMISSION ♦ FREQUENCY DEPENDENCE ♦ LASERS ♦ PHONONS ♦ PULSES ♦ RELAXATION ♦ SCATTERING|
|Abstract||We report on the observation of an approximately linear reduction in the maximum operating temperature with an increasing emission frequency for terahertz quantum-cascade lasers between 4.2 and 5.4 THz. These lasers are based on the same design type, but vary in period length and barrier height for the cascade structure. The sample emitting at the highest frequency around 5.4 THz can be operated in pulsed mode up to 56 K. We identify an additional relaxation channel for electrons by longitudinal optical phonon scattering from the upper to the lower laser level and increasing optical losses toward higher frequencies as major processes, leading to the observed temperature behavior.|
|Learning Resource Type||Article|
|Publisher Place||United States|
|Journal||Applied Physics Letters|
Ministry of Human Resource Development (MHRD) under its National Mission on Education through Information and Communication Technology (NMEICT) has initiated the National Digital Library of India (NDLI) project to develop a framework of virtual repository of learning resources with a single-window search facility. Filtered and federated searching is employed to facilitate focused searching so that learners can find out the right resource with least effort and in minimum time. NDLI is designed to hold content of any language and provides interface support for leading vernacular languages, (currently Hindi, Bengali and several other languages are available). It is designed to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is being developed to help students to prepare for entrance and competitive examinations, to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is being developed at Indian Institute of Technology Kharagpur.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Human Resource Development (MHRD), through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
For any issue or feedback, please write to email@example.com