TY  - JOUR
PB  - SciPost Foundation
DO  - 10.21468/SciPostPhys.12.5.160
TI  - Effective field theory of fluctuating wall in open systems: from a kink in Josephson junction to general domain wall
PY  - 2022/05/13
UR  - https://scipost.org/SciPostPhys.12.5.160
JF  - SciPost Physics
JA  - SciPost Phys.
VL  - 12
IS  - 5
SP  - 160
A1  - Fujii, Keisuke
AU  - Hongo, Masaru
AB  - We investigate macroscopic behaviors of fluctuating domain walls in nonequilibrium open systems with the help of the effective field theory based on symmetry. Since the domain wall in open systems breaks the translational symmetry, there appears a gapless excitation identified as the Nambu-Goldstone (NG) mode, which shows the non-propagating diffusive behavior in contrast to those in closed systems. After demonstrating the presence of the diffusive NG mode in the $(2+1)$-dimensional dissipative Josephson junction, we provide a symmetry-based general analysis for open systems breaking the one-dimensional translational symmetry. A general effective Lagrangian is constructed based on the Schwinger-Keldysh formalism, which supports the presence of the gapless diffusion mode in the fluctuation spectrum in the thin wall regime. Besides, we also identify a term peculiar to the open system, which possibly leads to the instability in the thick-wall regime or the nonlinear Kardar-Parisi-Zhang coupling in the thin-wall regime although it is absent in the Josephson junction.
ER  -

@Article{10.21468/SciPostPhys.12.5.160,
	title={{Effective field theory of fluctuating wall in open systems: from a kink in Josephson junction to general domain wall}},
	author={Keisuke Fujii and Masaru Hongo},
	journal={SciPost Phys.},
	volume={12},
	pages={160},
	year={2022},
	publisher={SciPost},
	doi={10.21468/SciPostPhys.12.5.160},
	url={https://scipost.org/10.21468/SciPostPhys.12.5.160},
}