Study of the Roberge-Weiss phase caused by external uniform classical electric field using lattice QCD approach

Journal of High Energy Physics

Regular Article - Theoretical Physics

Ji-Chong Yang¹  Xiao-Ting Chang¹  Jian-Xing Chen¹ 

[1] Department of Physics, Liaoning Normal University, No. 850 Huanghe Road, 116029, Dalian, P.R. China;Center for Theoretical and Experimental High Energy Physics, Liaoning Normal University, No. 850 Huanghe Road, 116029, Dalian, P.R. China;

关键词: Lattice QCD;    Phase Diagram or Equation of State;    Phase Transitions;   

DOI  :  10.1007/JHEP10(2022)053

 received in 2022-07-28, accepted in 2022-09-29,  发布年份 2022

来源: Springer

【 摘 要 】

The effect of an external electric field on the quark matter is an important question due to the presence of strong electric fields in heavy ion collisions. In the lattice QCD approach, the case of a real electric field suffers from the ‘sign problem’, and a classical electric field is often used similar as the case of chemical potential. Interestingly, in axial gauge a uniform classical electric field actually can correspond to an inhomogeneous imaginary chemical potential that varies with coordinate. On the other hand, with imaginary chemical potential, Roberge-Weiss (R-W) phase transition occurs. In this work, the case of a uniform classical electric field is studied by using lattice QCD approach, with the emphasis on the properties of the R-W phase. Novel phenomena show up at high temperatures. It is found that, the chiral condensation oscillates with z at high temperatures, and so is the absolute value of the Polyakov loop. It is verified that the charge density also oscillates with z at high temperatures. The Polyakov loop can be described by an ansatz Ap + Σq=u,dCq exp (LτQqiazeEz), where Ap is a complex number and Cd> 0, Cu ≥ 0 are real numbers that are fitted for different temperatures and electric field strengths. As a consequence, the behavior of the phase of Polyakov loop is different depending on whether the Polyakov loop encloses the origin, which implies a possible phase transition.

【 授权许可】

Unknown   
© The Author(s) 2022