Cryogen-free 3He / 4He mixed cooler for generating low temperatures down to below 10 mK and for investigating solid-state-based quantum systems (for more details, see specification).

A cryogen-free 3He / 4He mixed cooler for generating low temperatures down to below 10mK is being procured. The mixed cooler must allow the investigation and control of solid-state-based quantum systems. For this purpose, the mixer cooler must have the technical specifications that enable the experimental investigation of such systems. For this purpose, the mixer cooler must in particular have a sufficiently large sample volume to accommodate the experiments, a sufficiently high cooling capacity and a large number of microwave lines. The required technical specifications are listed in the service description.

Exclusion criteria with regard to the technical specifications are:

- the maximum floor space must be less than 400 cm x 300 cm, the maximum height less than 330 cm,

- To install the system, all parts of the mixing cryostat must fit through a door opening 2.13 m high and 1.6 m wide; the gas handling system must not exceed the dimensions HxWXD = 200 cm x 100 cm x 153 cm,

- the achievable base temperature must be <= 10 mK,

- the maximum cooling capacity must be> = 400 muW @ 100 mK and> 10 muW @ 20 mK,

- the sample volume available in the area of the mixing chamber plate must be> = 450 mm in diameter and> = 500 mm in height,

- the system may only have a single vacuum chamber (no additional internal vacuum seals in the cold area),

- the cooling times must be less than 36h,

- the delivery time must not be longer than 8 months.