




IR Filters
Measurement Infrastructure
IR Filters protect sensitive quantum devices from high-energy photons that might cause unwanted heating or decoherence.
Infrared Filters (IR Filters) protect sensitive quantum devices that operate below 1 K from high-energy photons that can cause unwanted heating or decoherence. In addition, they improve the thermalization of the center conductor in a coaxial line. A common application of IR Filters is in superconducting qubit devices where infrared radiation is suspected to generate quasi-particle excitations that reduce the coherence time of the qubit.
Product Highlights
1.0
IR Filters
Measurement Infrastructure
Filtering Noise
IR Filters absorb and dissipate high-frequency noise above the measurement frequency band.
Boosting Measurement Fidelity
IR Filters enable high-fidelity measurements within the measurement frequency band.
Low-loss Infrared Filter
2.0
IR Filters
Measurement Infrastructure

The Low-loss Infrared Filter blocks infrared radiation, while still enabling high signal fidelity within the passband of DC – 8 GHz, where it is optimized for high return loss and low insertion loss. The filter is designed with an attenuator footprint and can be directly installed between a flange feedthrough bulkhead and a coaxial cable. The Low-loss IR Filter has SMA jack (female) and SMA plug (male) connectors.
Technical Specifications
| Low-loss Infrared Filter | |
|---|---|
| Connector type | SMA (jack) – SMA (plug) |
| Dielectric fill | IR absorber |
| Insertion loss DC – 8 GHz | <1.3 dB |
| Return loss DC – 15 GHz | >20 dB |
| Total length | 25.4 mm |
S-Parameter Data

Typical microwave S-parameter data (transmission and reflection) of the Low-loss Infrared Filter.
High-loss Infrared Filter
3.0
IR Filters
Measurement Infrastructure

The High-loss Infrared Filter blocks infrared radiation, while still enabling high signal fidelity within the passband of DC – 1 GHz, where it is optimized for high return loss and low insertion loss. The filter is designed with an attenuator footprint and can be directly installed between a flange feedthrough bulkhead and a coaxial cable. The High-loss IR Filter has SMA jack (female) and SMA plug (male) connectors.
Technical Specifications
| High-loss Infrared Filter | |
|---|---|
| Connector type | SMA (jack) – SMA (plug) |
| Dielectric fill | IR absorber |
| Insertion loss DC – 700 MHz | <1.2 dB |
| Return loss DC – 10 GHz | >10 dB |
| Total length | 27.7 mm |
S-Parameter Data

Typical microwave S-parameter data (transmission and reflection) of the High-loss Infrared Filter.
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