Cooling Achieved by Rotating an Anisotropic Superconductor in a Constant Magnetic Field: An New Perspective

Authors

Manh-Huong Phan, University of South FloridaFollow
David Mandrus, University of Tennessee

Document Type

Article

Publication Date

2016

Digital Object Identifier (DOI)

https://doi.org/10.1063/1.4972124

Abstract

A new type of rotary coolers based on the temperature change (ΔT_rot) of an anisotropic superconductor when rotated in a constant magnetic field is proposed. We show that at low temperature the Sommerfeld coefficient γ(B,Θ) of a single crystalline superconductor, such as MgB2 and NbS2, sensitively depends on the applied magnetic field (B) and the orientation of the crystal axis (Θ), which is related to the electronic entropy (S_E) and temperature (T) via the expression: S_E=γT. A simple rotation of the crystal from one axis to one another in a constant magnetic field results in a change in γ and hence S_E: ΔS_E=ΔγT. A temperature change −Δ_Trot ∼ 0.94 K from a bath temperature of 2.5 K is achieved by simply rotating the single crystal MgB₂ by 90° with respect to the c-axis direction in a fixed field of 2 T. ΔT_rot can be tuned by adjusting the strength of B within a wide magnetic field range. Our study paves the way for development of new materials and cryogenic refrigerators that are potentially more energy-efficient, simplified, and compact.

Rights Information

This work is licensed under a Creative Commons Attribution 4.0 License.

Was this content written or created while at USF?

Yes

Citation / Publisher Attribution

AIP Advances, v. 6, issue 12, art. 125022

Scholar Commons Citation

Phan, Manh-Huong and Mandrus, David, "Cooling Achieved by Rotating an Anisotropic Superconductor in a Constant Magnetic Field: An New Perspective" (2016). Physics Faculty Publications. 14.
https://digitalcommons.usf.edu/phy_facpub/14