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Intersubband Emitters: GaAs-based Quantum-Cascade Lasers

Quantum-cascade lasers based on the GaAs/(Al,Ga)As materials system are already very useful radiation sources for many applications in the terahertz (THz) spectral region. This spectral region ranges typically from 0.1 to 10 THz bridging the electronics-based microwave region with the optics-based infrared region.

 

Due to their high emission powers and narrow line widths in continuous-wave operation, THz quantum-cascade lasers are excellent emitters of electromagnetic radiation for high-resolution spectroscopy. The THz region is of great current interest for spectroscopic applications, since rotational states of many molecules, impurity transitions in semiconductors, and fine-structure transitions in atoms as well as ions can result in THz absorption or emission. Currently, quantum-cascade lasers are unrivaled for local oscillators at frequencies above 3 THz in heterodyne detectors. Furthermore, imaging with THz radiation can be used for material testing or security purposes. The key challenges are the increase of the practical operating temperature and the wall plug efficiency of THz quantum-cascade lasers. The practical operating temperature is determined by an output power of at least 1 mW in continuous-wave operation.

Selected Publications

5 Author L. Schrottke , X. Lü , B. Röben , K. Biermann , T. Hagelschuer , M. Wienold , H.-W. Hübers , M. Hannemann , J. H. van Helden , J. Röpcke , H. T. Grahn
Title

High-performance GaAs/AlAs terahertz quantum-cascade lasers for spectroscopic applications

Source IEEE Trans. Terahertz Sci. Technol. , 10 , 133 ( 2019 )
DOI : 10.1109/TTHZ.2019.2957456 | 3129 Cite : Bibtex RIS
L. Schrottke, X. Lü, B. Röben, K. Biermann, T. Hagelschuer, M. Wienold, H.-W. Hübers, M. Hannemann, J. H. van Helden, J. Röpcke, and H. T. Grahn

4 Author B. Röben , X. Lü , K. Biermann , L. Schrottke , H. T. Grahn
Title

Terahertz quantum-cascade lasers for high-resolution spectroscopy of sharp absorption lines

Source J. Appl. Phys. , 125 , 151613 ( 2019 )
DOI : 10.1063/1.5079701 | Download: PDF | 3071 Cite : Bibtex RIS
B. Röben, X. Lü, K. Biermann, L. Schrottke, and H. T. Grahn

3 Author X. Lü , E. Luna , L. Schrottke , K. Biermann , H. T. Grahn
Title

Determination of the interface grading parameter for terahertz quantum-cascade laser structures based on transmission electron microscopy

Source Appl. Phys. Lett. , 113 , 172101 ( 2018 )
DOI : 10.1063/1.5042326 | Download: PDF | 3035 Cite : Bibtex RIS
X. Lü, E. Luna, L. Schrottke, K. Biermann, and H. T. Grahn

2 Author L. Schrottke , X. Lü , B. Röben , K. Biermann , M. Wienold , H. Richter , H.-W. Hübers , H. T. Grahn
Title

Intrinsic frequency tuning of terahertz quantum-cascade lasers

Source J. Appl. Phys. , 123 , 213102 ( 2018 )
DOI : 10.1063/1.5024480 | Download: PDF | 3015 Cite : Bibtex RIS
L. Schrottke, X. Lü, B. Röben, K. Biermann, M. Wienold, H. Richter, H.-W. Hübers, and H. T. Grahn

1 Author B. Röben , X. Lü , M. Hempel , K. Biermann , L. Schrottke , H. T. Grahn
Title

Terahertz quantum-cascade lasers as high-power and wideband, gapless sources for spectroscopy

Source Opt. Express , 25 , 16282 ( 2017 )
DOI : 10.1364/OE.25.016282 | Download: PDF | 2916 Cite : Bibtex RIS
B. Röben, X. Lü, M. Hempel, K. Biermann, L. Schrottke, and H. T. Grahn

Selected Publications from our Cooperation Partners

2 Author T. Alam , M. Wienold , X. Lü , K. Biermann , L. Schrottke , H. T. Grahn , H.-W. Hübers
Title

Frequency and power stabilization of a terahertz quantum-cascade laser using near-infrared optical excitation

Source Opt. Express , 27 , 36846 ( 2019 )
DOI : 10.1364/OE.27.036846 | Download: PDF | 3160 Cite : Bibtex RIS
T. Alam, M. Wienold, X. Lü, K. Biermann, L. Schrottke, H. T. Grahn, and H.-W. Hübers

1 Author T. Hagelschuer , H. Richter , M. Wienold , X. Lü , B. Röben , L. Schrottke , K. Biermann , H. T. Grahn , H.-W. Hübers
Title

A compact 4.75-THz source based on a quantum-cascade laser with a back-facet mirror

Source IEEE Trans. Terahertz Sci. Technol. , 9 , 606 ( 2019 )
DOI : 10.1109/TTHZ.2019.2935337 | 3140 Cite : Bibtex RIS
T. Hagelschuer, H. Richter, M. Wienold, X. Lü, B. Röben, L. Schrottke, K. Biermann, H. T. Grahn, and H.-W. Hübers

Contact

Prof. Dr. Holger T. Grahn

Head of Department 

+49 30 20377-318

htgrahn@pdi-berlin.de

Dr. Lutz Schrottke

Senior Scientist

+49 30 20377-339

lutz@pdi-berlin.de