Scalable Quantum Multicoax Cabling from Control Hardware to Quantum Processor


The newest form factors of Ardent’s TR Multicoax connectors support the many unique challenges of Quantum Computing applications. Density, substantial environmental changes, and an increasing need for more high-speed lanes are causing quantum computer designers to rethink traditional routing methods of individual cables. By utilizing superconducting materials like CuNi cables and the existing patented contact technology Ardent is known for, engineers will be able to drastically decrease real estate required by individual connectors and increase their channel count while improving signal integrity in their systems.

Key Benefits

  • Feedthrough offers leak-proof design (Max leak rate 2.00E-09 LTorr)
  • Variety of coaxial cable materials available (Flexible, CuNi, NbTi)
  • Extremely dense form factor (168+ channels in standard ISO disc)
  • Easily mate/de-mate multiple high-speed lanes

Quantum Computing / Cryogenic Applications

High Density TR Multicoax™ Cabling
  • High Density (2.54mm pitch) TR Multicoax™ bridges room temperature electronics to Hermetic Feedthrough for massive lane scale up
  • Internal coaxial cabling options include:
    • Low outgassing flexible
    • Semi-rigid
    • Non-magnetic
  • All metal, fully coaxial solderless compliant interface between connectors allows for noise floor crosstalk
  • Assemblies available in a variety of form factors, cable lengths, and pre-bent configurations (consult factory with requirements)
50Ω Hermetic Feedthrough
  • Ardent TR Multicoax™ compatible – substantial channel increase over traditional sursface mount connectors (2.54mm pitch)
  • Can be prepopulated in vacuum flanges, customer specific flanges, or sold individually
  • Tapped provisions allow quick connection of multiple TR Multicoax™ at once
  • Robust interface – rated up to 1000 mating cycles
In-Line Cryogenic Attenuation
  • TR Multicoax™ compatible – Substantial channel increase over traditional surface mount connectors (2.54mm pitch)
  • Manufactured with approved cryogenic materials for thermalization, outgassing, mechanical integrity
  • Chip-style cryogenic attenuator design on thermally conductive dielectric (conductive epoxy bonded substrate)
  • Frequency: DC to 12 GHz
  • Multiple attenuation values available (0, 10, 20 dB)
  • 16-channel (2×8) form factor (consult factory for additional form factors)
Advanced Near-Processor Solutions
  • Customizable TR Multicoax™ assemblies for connection of final stage to processor
  • Light blocking connection between stages
  • Right angle low-profile form factors for near processor connection
  • Alternative coaxial connector options available (SMA, SMP)
  • All metal sockets and interposers available for chip-to-board and board-to-board connections
  • Coaxial down to 1mm pitch
  • Non-coaxial down to .4mm pitch
  • Non-magnetic materials available

Ardent Solutions

Ardent Concepts Patented Contact Technology

Contact Overview

Signal Integrity

Ardent’s interconnect technology was born of a simple concept: What if we could eliminate the barrel and the plunger from a traditional “pogo” style spring pin and make the spring inside behave like an electrical contact instead of behaving like an inductor at multi-GHz speeds?


Our products are all based on solderless compression mount technology enabling more reliable and electrically repeatable performance over time and across programs. Our solderless compression products allow our customers to be agile in changing their designs without having to scrap entire projects and printed circuit boards with components soldered to the board. This leads to enhanced flexibility and cost savings.


Contacts can be arranged in pitches down to 0.4mm (grid array) and 2.54mm signal-to-signal (coaxial array) to scale up the number of lanes in any system.

Mechanical Reliability

Mil-Spec qualified and rated for thousands of cycles in the harshest environments, Ardent’s patented technologies are production proven with over 19 years of field use for test and measurement and OEM interconnect.

Spring Probe™

  • Scalable solutions for connectors down to 0.4mm pitch
  • Eliminates the barrel and the plunger from a traditional “pogo” style spring pin (fewer mechanical components to fail)
  • Patented “wipe action” of the coils causes contacts to behave like a solid element instead of behaving like an inductor, resulting in exceptionally clean AC performance in an extremely short electrical path


  • Cost-effective automation loaded contacts
  • High performance
  • Stamped contact for area array applications down to 0.6mm pitch
Connect-R ™

Contact Portfolio

TR Multicoax™ Series

Description and Applications


The TR Multicoax is a compression mount, multi-port cable assembly for carrying high speed signals. With true 70 GHz performance, TR is the highest performing solderless connector solution on the market today.

Compared to traditional solder down coaxial connectors like SMAs and SMPs, TR Multicoax takes up 80% less space on isolation discs and is easily re-usable as it can be moved from position to position on a printed circuit board without the need for any surface mount components.


  • Near-QPU
  • Dilution Refrigerator/Cryostat
  • Room Temperature Electronics
  • Vacuum Chambers

Features and Benefits

Connector Overview

  • Using patented spring probe technology, the TR Multicoax combines the Ardent Interposer technology and coaxial cable technology to create an unsurpassed solderless connector solution
  • By carefully controlling the geometry and material properties, the Ardent Interposer technology minimizes impedance discontinuities in an extremely electrically short transition enabling 70 GHz + performance

TR Multicoax™ Installation and Removal Tutorial

High Density TR Multicoax™ Cabling

Inner-Fridge Wiring

  • Variety of Coaxial cable materials available:
    • Flexible
    • CuNi
    • NbTi
  • 16, 24 channel options available
  • Custom lengths

Thermal Anchoring

  • Can be customized for thermal anchoring to minimize the heat load in a cryostat

Non-Magnetic Options

TR Multicoax 50Ω Hermetic Feedthrough

Description and Applications


50Ω Hermetic Feedthrough is ideal for applications where hermeticity is crucial to the transmission of RF signals. In these applications, TR Multicoax connectors are mated to the hermetic feedthrough on either end ensuring an impedance matched 50Ω channel between any two chambers. The feedthrough is fixed to a flange (such as an ISO disk) with screws in blind holes from the inside of the vacuum. The hermetic feedthrough is completely sealed using an epoxy potting.


  • Dilution Refrigerators/Cryogenic Devices
  • Quanum Computing
  • Vacuum Chambers
  • Defense/Aerospace

Features and Benefits

Density Comparison

TR Multicoax 50Ω Hermetic Feedthrough: 168 RF Lanes
SMA 50Ω Hermetic Feedthrough: 27 RF Lanes

Technical Information

Product Drawing (16 Channel)

Product Drawing (10x 16 Channel in flange)

Installation Diagram


Ganged Coaxial Attenuator

Description and Applications


High density thermalized low noise cryogenic bulkhead attenuator array for use with TR Multicoax™ connectors. Utilizes industry leading materials like Oxygen-free high thermal conductivity (OFHC) copper and NiCr on thermally conductive crystalline quartz dielectric provides minimal change in attenuation with temperature delta. Attenuation is offered in 0, 10, and 20 dB configurations and supports bandwidth up to 12 GHz. 16 channel form factor at a 2.54 mm pitch, signal to signal, saves valuable real estate in confined spaces.


  • Dilution Refrigerators/Cryogenic Devices
  • Quanum Computing
  • Vacuum Chambers
  • Defense/Aerospace

Features and Benefits

Product Drawing Preview

Contact Factory for Full Drawing

Mechanical Information

Installation Diagram


For Attenuator Block interfacing, the TR Multicoax connector must include shorter dowels and mounting screws.

Please be sure to note the requirement to mate with an Attenuator in your quote requests

Technical Information

Test Data

-10 dB Crystalline Quartz Substrate SN 1087

-20 dB Crystalline Quartz Substrate SN 1092

Advanced Near-Processor Solutions

Description and Applications


Ardent’s high-density, solderless TR Multicoax and interposer technology, allows engineers launch a large amount of RF or digital signals in a small area, while being able to place connectors in unparalleled proximity to the device under test.

Light-tight form factors (with provisions to panel mount into a thermally conductive flange, disk, or other mounting plate) and all metal sockets and interposers available for chip-to-board and board-to-board connections are available.


  • Dilution Refrigerators/Cryogenic Devices
  • Quanum Computing
  • Vacuum Chambers
  • Defense/Aerospace

Panel Mount for Light-Tight Systems

  • Panel mount TR = feedthrough to light-tight enclosure
  • Blind-Mate another TR to reach samples within enclosure
  • Heat dissipation from the thermal anchor to the coax center conductor
  • TR density allows higher # of coax lines
    • 160 lines – 55mm x 85mm
    • Fewer screws than SMA/SMP = faster install and reconfiguration

Near Quantum Processor Solutions

  • High-density connectors bring coax lines closer to sample
    • More signals + shorter trace
  • Right angle FF for low clearance areas
    • Light-tight enclosure
    • Shielding cans
  • Solderless connection
    • Stable
    • Reliable
    • Reconfigurable

High-Density Solderless Interposers

  • Solderless connection substrate → sample
    • No wire bonds
    • No indium bumps
    • Save components between revisions
    • ≥ 0.4mm pin pitch (square grid)
    • 1,000+ pins per CA
    • DC – 30 GHz signal frequency
    • Low outgassing materials

Contact Factory