标题： 变分量子相变边界场的模拟 显示英文标题

标题： Variational simulation of quantum phase transitions induced by boundary fields

摘要： 量子相变的表征是理解物质量子相的基本任务，在量子技术中具有许多潜在应用。 在本工作中，我们使用数字量子模拟作为资源，从理论和实验上研究量子相变。 更具体地说，我们将变分量子本征求解器（VQE）算法应用于存在边界磁场的一维自旋-$1/2$横场伊辛链。 这些场可以引发丰富的相图，包括一级相变线以及连续润湿转变，这是经典润湿表面现象的量子版本。 我们展示了相关量子电路的无噪声模拟结果以及来自超导量子处理器的硬件结果。 对于相图的不同区域，量子算法使我们能够预测导致系统中发生一阶或二阶相变的磁场临界值。 显示英文摘要

摘要： The characterization of quantum phase transitions is a fundamental task for the understanding of quantum phases of matter, with a number of potential applications in quantum technologies. In this work, we use digital quantum simulation as a resource to theoretically and experimentally study quantum phase transitions. More specifically, we implement the variational quantum eigensolver (VQE) algorithm to the one-dimensional spin-$1/2$ transverse-field Ising chain in the presence of boundary magnetic fields. Such fields can induce a rich phase diagram, including a first-order line and also a continuous wetting transition, which is a quantum version of the classical wetting surface phenomenon. We present results for noiseless simulations of the associated quantum circuits as well as hardware results taken from a superconducting quantum processor. For different regions of the phase diagram, the quantum algorithm allows us to predict the critical value of the magnetic fields responsible for either the first or second-order transitions occuring in the system.