PCA-44-16-16-1030-x
Photoconductive THz antenna for laser excitation wavelengths λ ~ 990 nm … 1060 nm
PCA – Photoconductive Antenna
PCA-44-16-16-1030-0 - unmounted antenna chip 2 mm x 2 mm with 4 bond contact pads
PCA-44-16-16-1030-h - mounted antenna on hyperhemispherical silicon substrate lens
PCA-44-16-16-1030-a - mounted antenna on aspheric silicon substrate lens
PCA applications
The PCA can be used as terahertz (THz) emitter or detector in pulsed laser gated THz measurement systems for time-domain spectroscopy and as photomixing emitter or detector in tunable cw THz measurement systems in the frequency region from 0.1 to 1.5 THz. The antenna delivers a large signal at frequencies below 500 GHz.
Main PCA data
- Laser excitation wavelength λ~ 1030 nm
- Bandwidth ~ 1 THz
Antenna design
Antenna parameters
Electrical parameters
Parameter
minimum ratings
standard
maximum ratings
Dark resistance W
5 GW
10 GW
15 G
Dark current @ 10 V
500 pA
2 nA
5 nA
Voltage
40 V
50 V
Dark current voltage characteristic at T = 300 K
Optical excitation parameters
Parameter
minimum ratings
standard
maximum ratings
Excitation laser wavelength
990 nm
1030 nm
1060 nm
Optical reflectance
60 % @ 990 nm
52 % @ 1030 nm
65 % @ 1060 nm
Optical mean power
40 mW
80 mW
Carrier recovery time
300 fs
Spectral reflectance
Mounted PCA on hyperhemispherical silicon substrate lens: PCA-44-16-16-1030-h
Photoconductive antenna
substrate
semi-insulating GaAs
chip area
2 mm x 2 mm
thickness t
600 µm
Hyperhemispherical lens
material
undoped HRFZ-silicon,
specific resistance r
>10 kWcm
refractive index n
3.4
diameter
12 mm
height h
7.1 mm
distance d
7.7 mm
Terahertz beam
collection angle α
57°
divergence angle ß
15°
virtual focus length L
26.4 mm
Aluminuim mount
25.4 mm diameter, 6 mm thick
Coaxial cable
type RG178 B/U, impedance 50Ω, capacitance 96pF/m, 1 m long
Connector type
BNC or SMA
- The PCA chip is optically adjusted and glued on the hyperhemispherical silicon lens. The alignment of the PCA chip centre is done with respect to the optical axis of the silicon lens.
- The silicon lens is glued on the aluminium mount.
- The two antenna contacts are wire bonded on a printed circuit board, which provides the connection to a 1m long coaxial cable with BNC or SMA connector
- A central hole in the aluminium mount allows the Terahertz radiation to escape from the hyperhemispherical silicon lens
Mounted PCA onaspheric silicon substrate lens: PCA-44-16-16-1030-a
Photoconductive antenna
substrate
semi-insulating GaAs
chip area
2 mm x 2 mm
thickness t
600 µm
Aspheric lens
material
undoped HRFZ-silicon
specific resistance r
>10 kWcm
refractive index n
3.4
diameter
12 mm
height h
8 mm
distance d
8.6 mm
rough AR surface
Terahertz beam
focal length f
50 mm
collection angle α
57.6°
convergence angle ß
6.8°
Airy disc diameter
at 300 GHz
5 mm
at 1 THz
1.5 mm
at 3 THz
0.5 mm
Aluminium mount
25.4 mm diameter, 6 mm thick
Coaxial cable
type RG178 B/U, impedance 50Ω, capacitance 96pF/m, 1 m long
Connector type
BNC or SMA
- The PCA chip is optically adjusted and glued on the aspheric silicon lens. The alignment of the PCA chip centre is done with respect to the optical axis of the silicon lens.
- The silicon lens is glued on the aluminium mount.
- The two antenna contacts are wire bonded on a printed circuit board, which provides the connection to a 1m long coaxial cable with BNC or SMA connector
- A central hole in the aluminium mount allows the Terahertz radiation to escape from the aspheric silicon lens as a collimated beam with a focus 50 mm away and an Airy disc diameter dependent on the THz frequency
描述 [描述] • Antenna length l: 44 µm<br />• Gap distance g: 16 µm<br />• Gap width w: 16 µm<br />• Laser wavelength λ: 990 nm .. 1060 nm