Design and performance of a THz emission and detection setup based on a semi-insulating GaAs emitter

• DOI: 10.1063/1.1459095
• Publication Date: 2002-07-26T13:27:17Z
• Authors: G. Zhao; R. N. Schouten; N. van der Valk; W. Th. Wenckebach; P. C. M. Planken
• Keywords: Crystal (programming language)

We have built a relatively simple, highly efficient, THz emission and detection system centered around 15 fs Ti:sapphire laser. In the system, 200 mW of laser power is focused to 120 μm diam spot between two silverpaint electrodes on surface semi-insulating GaAs crystal, kept at temperature near 300 K, biased with 50 kHz, ±400 V square wave. Using rapid delay scanning lock-in we obtain probe quantum-noise limited signals using standard electro-optic scheme 1-mm-thick (110) oriented ZnTe crystal or 0.1-mm-thick GaP crystal. The maximum THz-induced differential signal that observe ΔI/I=7×10−3, corresponding peak amplitude 95 V/cm. average was measured be about 40 μW, our knowledge, highest reported so far generated oscillators as pump source. uses off-the-shelf electronics requires no microfabrication techniques.