Tera-SED
Large area THz emitter
• Large-area terahertz emitter
• Low external bias voltages
• No external cooling required
• Superior interdigitated design
Overview
Efficient sources of Terahertz (THz) radiation are of great importance for a large variety of scientific and technological applications. Important key factors are a large bandwidth and a high THz electric field amplitude. This usually implies a large emitter area and in conventional concepts requires high bias voltages (several hundreds of volts) in order to achieve the necessary bias field strengths, typically in the kV/cm range. The key advantage of the Tera-SED is the unique combination of large active area and low bias voltage requirement.
Technical information
The Tera-SED is a planar large-area GaAs-based photoconductive emitter for impulsive generation of broadband THz radiation with a superior design. It features a novel interdigitated electrode MSM structure which allows for a large active area with kV/cmbias fields between individual electrodes. Only low external bias voltages are required, eliminating the need for a pulsed, high-voltage supply. Its flexible scalable device technology makes Tera-SED an efficient and versatile THz emitter.
Tera-SED requires no external cooling. It comes attached to a metal holder fitting into 1-inch optics mounts. Ease of use and hassle-free alignment are key assets.
Tera-SED is available in two different versions: 10x10 mm2 usable area intended for use with amplified fs-laser systems (pulse energy up to 300 μJ, saturating from ~10 μJ) and 3x3 mm2 usable area best suited for use with fs-laser oscillators.
Key device characteristics
Tera-SED3
Tera-SED10
Size
3x3 mm2
10x10 mm2
Peak emission frequency
1.0-1.5 THz
Spectral width (@-10 dB)
~2.5 THz
Pulse energy
7.5 nJ
10 µJ
Max.opt. excitation intensity
8 W/mm2
Max.opt. excitation power
650 mW
Optical excitation wavelength
700-850 nm
Pulsed THz field amplitude:
< 5kV/cm
Low bias voltage (DC or switchable)1
1-30 V
Bias modulation frequency
DC to 100 kHz
Duty cycle2
5% to 100% (cw)
1 max. bias voltage depends on active area and type of usage.
2 max. duty cycle depends on active area and type of usage.
Electrical performance parameters*
Vbias
duty cycle
THz field amplitude
Tera-SED3
up to 10 V
CW
100 V/cm (@10 V)
7.5 nJ pulse energy
10 V-20 V
50%
200 V/cm (@ 20 V)
Spotsize
300 μm max. 30 V
10%
300 V/cm
Tera-SED10
up to 5 V
CW
1000 V/cm (@5V)
10 μJ pulse energy
5 V-20 V
50%
2000 V/cm (@20 V)
Spotsize 2 to 6 mm
max. 25 V
5%
5000 V/cm
* Typical values only. Actual field strengths may vary depending on specific experimental conditions.