Nonrelativistic CFTs at Large Charge: Casimir Energy and Logarithmic Enhancements


The unitary Fermi gas, by virtue of its description as a nonrelativistic conformal field theory, has proven an interesting system by which the quantum properties of CFT can be held to experimental verification. Here, we examine the structure of conformal dimensions of charge-Q operators in nonrelativistic CFT, in the large-Q regime, from the non-linear sigma model perspective. We discuss in detail the renormalization of edge divergences using dimensional regularization, elucidating the presence of log⁡(Q) terms in the large-charge expansion. Finally we use dimensional regularization to compute the universal one-loop log⁡(Q) contribution to the ground-state energy in d=3

JHEP 05 (2022) 135