bPCA-180-05-10-1550-x
Photoconductive THz antenna for laser excitation wavelengths λ ~ 1550 nm
PCA – Photo Conductive Antenna
Spectral performance
Antenna parameters
Parameter
minimum ratings standard maximum ratings Dark resistance
100 kW 300 kW 500 kW Voltage
10 V 10 V Optical mean power @ 50 – 100 MHz repetition rate
10 mW 12 mW Pulse fluence
250 µJ/cm2 300 µJ/cm2
Attention: The F-number of the optical lens focusing the laser beam onto the antenna gap must be larger then a certain value to avoid too high pulse fluency. This means, that the minimum diameter of the focused beam waist must be about 120 % of the gap distance g. For a Gaussian beam the minimum focus length fmin of the optical lens can be estimated as
with
g – gap distance of the antenna
λ - laser wavelength
D – diameter of the laser beam hitting the focusing lens.
For λ = 1,5 µm and g = 5 µm the minimum possible F-number of the lens is fmin/D = π.
Antenna design
Order information
bPCA-180-05-10-1550-x Photoconductive antenna
length l = 180 µm
gap g = 5 µm
width w = 10 µm
laser wavelength l = 1550 nm
x denotes the type of mounting as follows:
x = 0 unmounted chip 4 mm x 4 mm with 2 bond contact pads
x = h mounted on an Al disc with 25.4 mm ∅ and hyperhemispherical siliconsubstrate lens, 1m coaxial cable with BNC or SMA connector
x = a mounted on an Al disc with 25.4 mm ∅ and aspheric focusing silicon substratelens, 1m coaxial cable with BNC or SMA connector
x = c mounted on an Al disc with 25.4 mm ∅ and aspheric collimating siliconsubstrate lens CL-12 for 12 mm THz beam diameter, 1m coaxial cable withBNC or SMA connector
x = h-f fiber coupled antenna with hyperhemispherical silicon substrate lens
x = l with aspheric focusing optical lens for free space laser excitation
x = p with preamplifier for detector antenna
描述 [描述] • Antenna length l: 180 µm<br />• Gap distance g: 5 µm<br />• Gap width w: 10 µm<br />• Laser wavelength λ: ≤ 1550 nm