New type liquid He free3He Cryostat using Commercial GM refrigerator

Phasor Analysis of Two-stage Gm-type Pulse Tube Refrigerator

A two-stage pulse tube refrigerator (PTR) is the simplest version of a multistage pulse tube refrigerator. A two-stage Gifford-McMahon (GM) has been used for nearly all of the cryopumps. The phasor analysis of the Gifford-McMahan (GM)-type pulse tube refrrigerator (PTR) have not explained detail in the earlier study. In the present work, a detailed mass flow, enthalpy & phasor analysis for a tw...

Superconducting transmission lines for use in a He dilution refrigerator

We compare two superconducting transmission lines for use in a He dilution refrigerator using a NbTi wire inner conductor with NbTi foil and CuNi tubing outer conductors. The heat transfer is calculated using the Wiedermann-Franz Law, and the impedance and power loss are measured using a network analyzer at room temperature and at 4K. The transmission line with CuNi tubing is easy to construct,...

Thermodynamics of Liquid 'he- " He Mixtures

The osmotic pressure of 3He-4He solutions is shown to follow in a natural way from the separation of the specific heat in a quasiparticle contribution and a 4He-contribution. Expressions for important thermodynamic properties such as the chemical potentials, the internal energy, the entropy, specific heat, osmotic pressure, etc. are given for the case the quasiparticle gas can be treated as a n...

New Surface Relaxation Mechanism for Liquid 3 He in

New phases of liquid He at low temperature