Variational study of a two-level system coupled to a harmonic oscillator in an ultrastrong-coupling regime

被引：50

作者：

Hwang, Myung-Joong ^{[1
]}

Choi, Mahn-Soo ^{[2
]}

机构：

[1] Pohang Univ Sci & Technol, Dept Phys, Pohang 790784, South Korea

[2] Korea Univ, Dept Phys, Seoul 136713, South Korea

来源：

PHYSICAL REVIEW A | 2010年 / 82卷 / 02期

关键词：

GROUND-STATE; QUANTUM;

D O I：

10.1103/PhysRevA.82.025802

中图分类号：

O43 [光学];

学科分类号：

070207 ; 0803 ;

摘要：

The nonclassical behavior of a two-level system coupled to a harmonic oscillator is investigated in the ultrastrong coupling regime. We revisit the variational solution of the ground state and find that the existing solutions do not account accurately for nonclassical effects such as squeezing. We suggest a trial wave function and demonstrate that it has an excellent accuracy for the quantum correlation effects as well as for the energy.

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页数：4

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