TY  - JOUR
PB  - SciPost Foundation
DO  - 10.21468/SciPostPhysCore.7.3.063
TI  - Efficient construction of the Feynman-Vernon influence functional as matrix product states
PY  - 2024/09/13
UR  - https://scipost.org/SciPostPhysCore.7.3.063
JF  - SciPost Physics Core
JA  - SciPost Phys. Core
VL  - 7
IS  - 3
SP  - 063
A1  - Guo, Chu
AU  - Chen, Ruofan
AB  - The time-evolving matrix product operator (TEMPO) method has become a very competitive numerical method for studying the real-time dynamics of quantum impurity problems. For small impurities, the most challenging calculation in TEMPO is to construct the matrix product state representation of the Feynman-Vernon influence functional. In this work we propose an efficient method for this task, which exploits the time-translationally invariant property of the influence functional. The required number of matrix product state multiplication in our method is almost independent of the total evolution time, as compared to the method originally used in TEMPO which requires a linearly scaling number of multiplications. The accuracy and efficiency of this method are demonstrated for the Toulouse model and the single impurity Anderson model.
ER  -

@Article{10.21468/SciPostPhysCore.7.3.063,
	title={{Efficient construction of the Feynman-Vernon influence functional as matrix product states}},
	author={Chu Guo and Ruofan Chen},
	journal={SciPost Phys. Core},
	volume={7},
	pages={063},
	year={2024},
	publisher={SciPost},
	doi={10.21468/SciPostPhysCore.7.3.063},
	url={https://scipost.org/10.21468/SciPostPhysCore.7.3.063},
}