Enhancement of THz emission from semiconductor surfaces

M.B. Johnston1, A. Dowd1, D.M. Whittaker2, A. Corchia1, A.G. Davies1, E.H. Linfield1
1Department of Physics, Cavendish Laboratory, University of Cambridge, Cambridge, UK
2Departments of Physics and Astronomy, University of Sheffield, Sheffield, UK

Tóm tắt

We have studied the generation of coherent pulses of terahertz (THz) radiation from semiconductor surfaces both experimentally and using a Monte-Carlo carrier dynamics simulation. Collimated THz beams are observed from surface-field THz emitters and three methods of improving the efficiency of these emitters are demonstrated: (i) by applying a magnetic field, (ii) by reducing the effective refractive index of the device and (iii) by altering the geometry of the device. An enhancement of 21/spl times/ is seen in a prism based GaAs/InAs THz emitter.

Từ khóa

#Surface emitting lasers #Semiconductor lasers #Optical pulses #Quantum cascade lasers #Optical pulse generation #Photonic band gap #Charge carrier processes #Gas lasers #Power lasers #Laser excitation

Tài liệu tham khảo

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