标题： 玻色三聚体结合长度的有效场论分析至次领头阶 显示英文标题

标题： Effective field theory analysis of boson-trimer bond lengths to next-to-leading order

摘要： 冷氦原子是一个独特的系统，在其中单个激发的三体埃菲莫夫态自然出现，不需要外部磁场。虽然冷氦原子的三体束缚态能量以前已经研究过，但最近的实验技术也使其结构得以研究。氦原子之间的弱相互作用导致氦-氦（二聚体）散射长度$a$远大于氦-氦相互作用的有效范围$r$。这一特性被用于一种理论中，该理论系统地将可观测量展开为$r/a$的幂次，称为短程有效场论（srEFT），这种理论成功地用于研究冷原子系统的性质。使用srEFT，我们研究了冷氦原子三体基态和激发的埃菲莫夫态中原子的平均键长。在srEFT的领头阶（次领头阶），我们发现$^4$氦三聚体基态的平均键长为 8.35(33) Å (10.29(2) Å)，而激发的$^4$氦三聚体埃菲莫夫态的平均键长为 103(4) Å (105.3(2) Å)。 显示英文摘要

摘要： Cold Helium atoms are a unique system where a single excited three-body Efimov state occurs, naturally, without the need for an external magnetic field. While three-body bound state energies of cold Helium atoms have previously been investigated, recent experimental techniques have allowed their structure to also be studied. The weak interaction between Helium atoms leads to a helium-helium (dimer) scattering length, $a$, much larger than the helium-helium effective range of interaction, $r$. This feature is exploited in a theory that systematically expands observables in powers of $r/a$, known as short range effective field theory (srEFT), which has been used successfully to investigate properties of cold atom systems. Using srEFT we investigate the average bond length of atoms in the three-body ground state and excited Efimov state of cold Helium atoms. At leading-order (next-to-leading order) in srEFT, we find the average bond length of the $^4$He trimer ground state is 8.35(33) \r{A} (10.29(2) \r{A}) and the average bond length of the excited $^4$He trimer Efimov state is 103(4) \r{A} (105.3(2) \r{A}).