近日，美国斯坦福大学的Benjamin L. Lev及其研究团队取得一项新进展。经过不懈努力，他们对量子多体疤痕状态非线性响应中的幽灵能量进行研究。相关研究成果已于2024年8月15日在国际权威学术期刊《科学》上发表。

该研究团队使用具有吸引相互作用的镝气体来生成疤痕状态，这些状态足够稳定，可以在保持其特性的同时被驱动到强非线性区域。

研究人员测量了在猝灭约束势之后，动能和总能量的演化。尽管裸相互作用是吸引的，但原子的行为却像是相互排斥：在气体被压缩时，它们的动能反常地减小。

研究人员通过将实验结果与广义流体动力学计算进行基准测试，来量化缺失的“幽灵”能量。研究人员提供证据表明，缺失的动能是由未检测到的高动量原子携带的。

据悉，量子多体疤痕状态以其非热态、低纠缠态以及存在于高能状态中的特性而著称。

附：英文原文

Title: Phantom energy in the nonlinear response of a quantum many-body scar state

Author: Kangning Yang, Yicheng Zhang, Kuan-Yu Li, Kuan-Yu Lin, Sarang Gopalakrishnan, Marcos Rigol, Benjamin L. Lev

Issue&Volume: 2024-08-15

Abstract: Quantum many-body scars are notable as nonthermal, low-entanglement states that exist at high energies. Here, we use attractively interacting dysprosium gases to create scar states that are stable enough to be driven into a strongly nonlinear regime while retaining their character. We measure how the kinetic and total energies evolve after quenching the confining potential. Although the bare interactions are attractive, the atoms behave as if they repel each other: Their kinetic energy paradoxically decreases as the gas is compressed. The missing “phantom” energy is quantified by benchmarking our experimental results against generalized hydrodynamics calculations. We present evidence that the missing kinetic energy is carried by undetected, very high-momentum atoms.

DOI: 10.1126/science.adk8978

Source: https://www.science.org/doi/10.1126/science.adk8978