Cryogenic Microwave Filter

Quiet wiring for quantum experiments.

High-attenuation cryogenic microwave filtering in a compact, laboratory-proven format. Designed for reliable operation from room temperature to the millikelvin range, with strong thermalization and robust long-term performance.

Made in Japan · Custom line count, connectors, materials, and geometry available on request

Cryogenic microwave filter device
Attenuation
S21 ≤ −120 dB
Frequency Range
>26.5 GHz
Temperature
300 K to <10 mK
Configuration
24 lines / 12 twisted pairs

Key features

  • Classic distributed metal-powder filter architecture used for decades in laboratories worldwide.
  • Excellent thermalization of all signal lines. Internal conductors are fully potted in thermally conductive metal-loaded epoxy with no loose powder.
  • Mechanical stability under repeated thermal cycling and magnetic field cycling.
  • Fully compatible with dilution refrigerators and cryogenic vacuum environments.
  • Machined C1020 oxygen-free copper housing with gold plating for strong thermal anchoring and corrosion resistance.
  • Compact mechanical design for mixing-chamber mounting.

Why this design

The simplicity of the classic metal-powder approach is one of its strengths: it has been adopted broadly across low-temperature experimental physics because it is robust, repeatable, and dependable over long installations.

This filter is intended for experiments that require aggressive suppression of microwave noise on DC and low-frequency wiring without sacrificing good thermalization at the cold stage.

Electrical specifications

Transmission Typical S21 ≤ −120 dB from 5–26.5 GHz
DC resistance < 25 Ω per line
Capacitance < 50 pF
Recommended bandwidth DC to ~1 MHz

Mechanical specifications

Lines 24 lines (12 twisted pairs)
Connectors 25-pin Micro-D
Housing C1020 oxygen-free copper (99.96%) with gold plating
Size 90 × 50 × 14 mm
Compact: 70 × 50 × 14 mm
Mounting 8 × M3 holes; 40 × 20 mm pattern (center-to-center)

Products

Metal‑powder microwave filter

High‑attenuation cryogenic RF filter for dilution refrigerator wiring and heavy microwave noise suppression.

RC low‑pass cryogenic filter

Compact multi‑stage RC filter for DC bias and sensor lines. Steep roll‑off from ~100 kHz with strong RF suppression.

Applications

Superconducting qubits Semiconductor quantum devices Mesoscopic transport Quantum Hall experiments Single-electron measurements Single-photon measurements Ultra-low-noise transport General cryogenic wiring

Contact

For pricing, custom configurations, or technical questions, please contact us by email.

Please include your institution, application, required line count, connector preference, and any custom geometry requirements.