Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Enhancement and Discontinuity of Effective Mass through the First-Order
  Metamagnetic Transition in UTe$_2$   Metamagnetic transitions in the novel spin-triplet superconductor UTe$_2$
were investigated through the newly developed simultaneous measurements of
magnetization and sample temperature for the field along the orthorhombic
$b$-axis and close to the [011] direction, where reentrant superconductivity
(RSC) is detected below and above the first-order metamagnetic transition field
$H_{\rm m}$. Combining the Maxwell's relation and the Clausius-Clapeyron
equation, we obtained the field dependence of Sommerfeld coefficient $\gamma$
through the first-order metamagnetic transition. A significant enhancement of
the effective mass toward $H_{\rm m}$ were detected for both field directions.
On the other hand, above $H_{\rm m}$, the effective mass discontinuously
decreases for $H~||~b$, while it discontinuously increases for $H~||~\sim
[011]$, which seems to make a crucial role for the RSC.

29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
0
The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th