AUTHOR=Castro-Villarreal Pavel , Ramírez J. E. 

TITLE=Semiflexible Polymer Enclosed in a 3D Compact Domain

JOURNAL=Frontiers in Physics

VOLUME=9

YEAR=2021

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2021.642364

DOI=10.3389/fphy.2021.642364

ISSN=2296-424X

ABSTRACT=<p>The conformational states of a semiflexible polymer enclosed in a volume <inline-formula id="inf1"><mml:math id="m1" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>V</mml:mi><mml:mo>:</mml:mo><mml:mo>=</mml:mo><mml:msup><mml:mi>ℓ</mml:mi><mml:mn>3</mml:mn></mml:msup></mml:mrow></mml:math></inline-formula> are studied as stochastic realizations of paths using the stochastic curvature approach developed in [Rev. E 100, 012503 (2019)], in the regime whenever <inline-formula id="inf2"><mml:math id="m2" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mrow><mml:mrow><mml:mn>3</mml:mn><mml:mi>ℓ</mml:mi></mml:mrow><mml:mo>/</mml:mo><mml:mrow><mml:msub><mml:mi>ℓ</mml:mi><mml:mi>p</mml:mi></mml:msub></mml:mrow></mml:mrow><mml:mo>&gt;</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:math></inline-formula>, where <inline-formula id="inf3"><mml:math id="m3" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>ℓ</mml:mi><mml:mi>p</mml:mi></mml:msub></mml:mrow></mml:math></inline-formula> is the persistence length. The cases of a semiflexible polymer enclosed in a cube and sphere are considered. In these cases, we explore the Spakowitz–Wang–type polymer shape transition, where the critical persistence length distinguishes between an oscillating and a monotonic phase at the level of the mean-square end-to-end distance. This shape transition provides evidence of a universal signature of the behavior of a semiflexible polymer confined in a compact domain.</p>