On September 26, Physical Review X (PRX, with an impact factor of 14.4) published online the latest achievement, entitled “Exponential Thermal Tensor Network Approach for Quantum Lattice Models”, by Professor Chen Ziyu and Associate Professor Li Wei from the Key Laboratory of Micro-Nano Measurement-Manipulation and Physics (Ministry of Education) of Beihang University in collaboration with their co-authors. Associate Professor Li and Andreas Weichselbaum of Brookhaven National Laboratory are both corresponding authors of the paper, Beihang students Chen Bin-Bin and Chen Lei being the co-primary authors.
Among all the interacting atoms that form the various materials in the world, there are those correlated quantum materials with extraordinary electronic structure and magnetic properties such as high-temperature superconductivity, spin liquids, and so on. They need to be studied based on micro models so as to unearth their potential applications in areas such as quantum computation. What bridges theory and experiments is the comparison between computational simulations and experiments on thermodynamic properties such as magnetization and heat capacity. However, it is a complex project which lacks effective computational methods—especially that of two-dimensional fermions—thus forming one of the major frontier issues in the concerned field.
Associate Professor Li has always been devoted to that field. He proposed linearized tensor renormalization group algorithm for the calculation of thermodynamic properties of quantum lattice model [Phys. Rev. Lett. 106, 127202 (2011)] in collaboration with his supervisor Professor Su Gang. In line with the method, the team of Associate Professor Li has developed and programmatically realized a new approach to obtain the density operator of a given temperature. Different from the traditional one, which will become both inaccurate and ineffective when it comes to compute the low-temperature properties of the two-dimensional system, the new approach named XTRG cools down along the axis of the reciprocal temperature exponential and thus simulates the thermodynamic properties of the quantum many-body system in cold temperatures (as in the graph below) with more precision.
The team of Associate Professor Li is expected to further their research on XTRG, and make more contributions to quantum many-body system computation.
The research has received great support from the National Natural Science Foundation of China (NSFC), the key project of National Natural Science Fund, Hundreds Talents Program of Beihang University, and Beihang Youth Talents Fund.
Physical Review X (PRX), as the journal with the highest impact factor under the American Physics Society, places a high value on academic interdisciplinary, academic innovation and fundamental breakthroughs, according to whose strict criteria no more than 300 papers are published every year.
Group Photo of Some Members of the Research Team
For more about the paper: https://journals.aps.org/prx/abstract/10.1103/PhysRevX.8.031082
Reported by Liu Rui
Edited by Song Chao and Li Siying
Translated by Li Siying