Cryogenic wire

Used to minimize heat leak into the sensor and cryogenic system, cryogenic wire has a much lower thermal conductivity (and higher electrical resistivity) than copper wire. The most common type of cryogenic wire is phosphor bronze. This wire is available in one-, two-, and four-lead configurations. Four-lead configurations are available as Quad-twist™ (two twisted pairs) or Quad-lead™ (ribbon). Wire gauge is 32 or 36 AWG, with polyimide or polyvinyl formal (Formvar®) used to insulate the wires. Other common cryogenic wires include manganin, nichrome heater wire, and WHD-30 heavy-duty copper wire. Cryogenic wire product overview...

Single-strand cryogenic wire — WSL-32, WSL-36

Lake Shore non-magnetic (NM) single lead (SL) wire is a non-ferromagnetic phosphor bronze (CuSnP alloy) wire. This single-strand wire has a relatively low temperature dependence of its resistance from room temperature to helium temperatures.

WSL-32 (32 AWG, polyimide insulation) can be used for sensor installations requiring stronger and more ‘rugged’ leads.

WSL-36 (36 AWG, clear Formvar® insulation) wire is recommended for general sensor installation.

Twisted lead wire — WCT-34

These low resistance twisted pair wires are ideal for extending the lead length of Lake Shore cryogenic Hall generators. They are silver-plated copper, 34 AWG with Teflon® insulation.

Duo-Twist™ cryogenic wire — WDT-32, WDT-36

Duo-Twist™ is a single twisted pair (2 leads) of 32 or 36 AWG non-ferromagnetic phosphor bronze wire twisted at 3.15 twists per centimeter (8 twists per inch). It is color coded: the cathode is green and the anode is clear. This polyimide-insulated wire is a good choice when any possibility of pickup noise to a diode sensor or sample by induced currents through the leads needs to be minimized.

Quad-Lead™ cryogenic wire — WQL-32, WQL-36

Quad-Lead™ wire is a 4-wire phosphor-bronze ‘ribbon cable,’ which makes heat sinking and dressing leads much easier than working with individual wires. Noninductive (bifilar) windings are simple to make for heat sinks and heaters using the Quad-Lead™ wire. In addition, this non-ferromagnetic wire is color coded for easy lead identification, and can be split to yield 2 wire pairs. Quad-Lead™ wire is also useful in standard 4-lead measurements in magnetic field applications due to its low magnetoresistance. It is insulated with polyimide.

Note: Quad-Lead™ wires are formed into a ‘ribbon cable’ using Bond Coat 999 bonding film. This bonding agent will soften above 160 to 180 °C. Individual wires can be separated either by heat or with a rotary-abrasion style mechanical stripper (recommended: Eraser company RT2S Magnet Wire Stripper). Do not separate the wires using any kind of sharp blade, as damage will result—download Separation of Quad-Lead™ Wires for more information.

Quad-Twist™ cryogenic wire — WQT-32, WQT-36

Quad-Twist™ is 2 twisted pairs (4 leads) of 32 or 36 AWG phosphor bronze wire. Each color coded pair incorporates 3.15 twists per centimeter (8 twists per inch), and the 2 pairs are entwined at 1.57 twists per centimeter (4 twists per inch).The 32 AWG is polyimide insulated and the 36 AWG is insulated with Formvar®. This wire is a good choice when pickup noise to a diode sensor or sample by induced currents through the leads needs to be minimized. Use one twisted pair for sensor excitation and the other twisted pair for sensor output voltage to minimize pickup of electromagnetic noise.

Manganin wire — WMW-30 , WMW-32, WMW-36

Lake Shore manganin wire is often used for cryostat wiring or heater requirements in nonmagnetic applications. This non-ferromagnetic wire is nominal 83% copper, 13% manganese, and 4% nickel. It comes in 30, 32, and 36 AWG with heavy Formvar® insulation.

Heavy-duty lead wire — WHD-30

This more rugged (30 AWG made from 7 38 AWG silver-plated twisted copper strands) wire is useful as a lead wire to resistance heaters in cryogenic environments where low resistance to the heater is required or desired. It is coated in black etched Teflon® for adhesion to epoxy.

Nichrome heater wire — WNC-32

This high resistance wire is typically used for heater requirements. The relatively large wire size provides sufficient surface area to dissipate the heat generated within the wire with only a moderate rise in wire temperature. It is nominal 80% nickel and 20% chromium and non-ferromagnetic. This 32 AWG wire is insulated with polyimide.

Note: We have had poor experience with heaters made using wire smaller than 32 AWG and supplying 25 W or more power. A possible alternative is one of our cartridge heaters.