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This is the raw data related to the publication "High-field THz pulses from a GaAs photoconductive emitter for non-linear THz studies". The file "THzPowerMeasurement.xlsx" is manually noted THz power reading from the locking. It is used for Figs. 2(a&b). The file "005-PCA-60V_100mW.thz" is the THz time-domain data corresponding to Fig2 (c).   The files "017******* to 027**********" are data corresponding to Figs 3(a&b). Plots in Figs. 4(b-d) are also calculated from these data files. The files "005-PCA-1point2mm.thz" are data used for THz spot diameter calculation.

We investigate here terahertz enhancement effects arising from micrometer and nanometer structured electrode features of photoconductive terahertz emitters. Nanostructured electrode based emitters utilizing the palsmonic effect are currently one of the hottest topics in the research field. We demonstrate here that even in the absence of any plasmonic resonance with the pump pulse, such structures can improve the antenna effect by enhancing the local d.c. electric field near the structure edges. Utilizing this effect in Hilbert-fractal and grating-like designs, enhancement of the THz field of up to a factor of ~ 2 is observed. We conclude that the cause of this THz emission enhancement in our emitters is different from the earlier reported plasmonic-electrode effect in a similar grating-like structure. In our structure, the proximity of photoexcited carriers to the electrodes and local bias field enhancement close to the metallization cause the enhanced efficiency. Due to the nature of this effect, the THz emission efficiency is almost independent of the pump laser polarization. Compared to the plasmonic effect, these effects work under relaxed device fabrication and operating conditions.

We present a scalable large-area terahertz (THz) emitter designed for excitation with 1.55 µm pump radiation. It is based on an InGaAs heterostructure combined with a microstructured electrode pattern. Electric fields of more than 2.5 V/cm in the THz focus are reached, the spectrum of the pulses extends up to 3 THz.

We present scalable large area terahertz (THz) emitters based on a nanoscale multilayer InGaAs/InAlAs heterostructure and a microstructured electrode pattern. The emitters are designed for pump lasers working at the telecommunication wavelength of 1.55µm. Electric THz fields of more than 2.5 V/cm are reached with moderate pump powers of 80 mW, the corresponding spectrum extends up to 3 THz. The saturation characteristics have been investigated for different pump laser spot sizes. For small pump powers of less than 50 mW the emitted THz field is nearly independent of the spot size, for higher pump powers and small spot sizes a clear saturation of the generated THz pulse can be observed. Hence the usage of scalable emitters is especially promising for high power fibre laser systems. The spectral content of the generated radiation is nearly independent of the parameters spot size, pump power, and bias voltage, which allows for stable operation in spectroscopic applications.

We report on scalable large-area terahertz emitters and detectors based on In0.53Ga0.47As/In0.52Al0.48As heterostructures for excitation with 1.55 µm radiation. Different geometries involving three different electrode gap sizes are compared with respect to THz emission, bias field distribution and Joule heating. The field distribution becomes more favorable for THz emission as gap size increases while Joule heating exhibits the opposite dependence. Best performance is found for emitters with a gap size of 7.5 µm. The scalable devices are furthermore employed as detectors. The scalable electrode geometry enables spatially integrated detection, which is attractive for specific applications.