涉及量子涨落和三体损失的 3D 偶极玻色-爱因斯坦凝聚体的基态
偏微分方程分析
2020-11-03 v1
摘要
我们考虑涉及量子涨落和三体损失的三维偶极玻色-爱因斯坦凝聚体的基态,其可等价地描述为 Gross-Pitaevskii 能量泛函的带正 L 2 L^2 L 2 约束的临界点 E ( u ) = 1 2 ∫ R 3 ∣ ∇ u ∣ 2 d x + λ 1 2 ∫ R 3 ∣ u ∣ 4 d x + λ 2 2 ∫ R 3 ( K ⋆ ∣ u ∣ 2 ) ∣ u ∣ 2 d x + 2 λ 3 p ∫ R 3 ∣ u ∣ p d x , E(u)\!=\!\frac{1}{2}\int_{{\mathbb{R}^3}} {|\nabla u|}^2dx+\frac{\lambda_{1}}{2}\int_{{\mathbb{R}^3}} {| u|}^4dx+\frac{\lambda_{2}}{2} \int_{\mathbb{R}^{3}}\left(K \star|u|^{2}\right)|u|^{2} d x+\frac{2\lambda_{3}}{p}\int_{{\mathbb{R}^3}} {|u|}^{p}dx, E ( u ) = 2 1 ∫ R 3 ∣∇ u ∣ 2 d x + 2 λ 1 ∫ R 3 ∣ u ∣ 4 d x + 2 λ 2 ∫ R 3 ( K ⋆ ∣ u ∣ 2 ) ∣ u ∣ 2 d x + p 2 λ 3 ∫ R 3 ∣ u ∣ p d x , 其中 2 < p < 10 3 2<p<\frac{10}{3} 2 < p < 3 10 ,λ 3 < 0 \lambda_{3}<0 λ 3 < 0 ,⋆ \star ⋆ 为卷积,K ( x ) = 1 − 3 cos 2 θ ( x ) ∣ x ∣ 3 K(x) \!=\! \frac{{1-3{{\cos }^2}\theta(x) }}{{{{| x |}^3}}} K ( x ) = ∣ x ∣ 3 1 − 3 c o s 2 θ ( x ) ,θ ( x ) \theta(x) θ ( x ) 为由 ( 0 , 0 , 1 ) (0,0,1) ( 0 , 0 , 1 ) 确定的偶极轴与向量 x x x 之间的夹角。若 λ 1 < 4 π 3 λ 2 ≤ 0 {\lambda _1} \!\!<\!\! \frac{4\pi} {3} {\lambda _2}\!\leq\! 0 λ 1 < 3 4 π λ 2 ≤ 0 或 λ 1 < − 8 π 3 λ 2 ≤ 0 {\lambda _1} \!\!<\!- \frac{8\pi}{3} {\lambda _2}\!\leq\! 0 λ 1 < − 3 8 π λ 2 ≤ 0 ,则 E ( u ) E(u) E ( u ) 在 L 2 L^2 L 2 -球面 S c : = { u ∈ H 1 ( R 3 ) : ∫ R 3 ∣ u ∣ 2 d x = c 2 } S_{c}\!:=\!\Big\{ u \!\in\! H^1({\mathbb{R}^3}): \int_{{\mathbb{R}^3}} {{|u|}^2}dx\!=\!c^2 \Big\} S c := { u ∈ H 1 ( R 3 ) : ∫ R 3 ∣ u ∣ 2 d x = c 2 } 上无界,因此我们转而研究局部极小问题 m ( c , R 0 ) : = inf u ∈ V R 0 c E ( u ) m(c,R_0)\!:=\!\inf _{u \in V^c_{R_0}} E(u) m ( c , R 0 ) := u ∈ V R 0 c inf E ( u ) 对合适的 R 0 > 0 R_0\!>\!0 R 0 > 0 ,其中 V R 0 c : = { u ∈ S c : ( ∫ R 3 ∣ ∇ u ∣ 2 d x ) 1 2 < R 0 } V^c_{R_0} \!:=\!\left\{u \!\in\! S_c : \big(\int_{{\mathbb{R}^3}} {{|\nabla u|}^2dx}\big)^{\frac{1}{2}} \!<\!R_0\right\} V R 0 c := { u ∈ S c : ( ∫ R 3 ∣∇ u ∣ 2 d x ) 2 1 < R 0 } 。我们证明 m ( c , R 0 ) m(c,R_0) m ( c , R 0 ) 被某个 u c > 0 u_c>0 u c > 0 达到,其为一个稳定基态。进一步,通过改进 m ( c , R 0 ) m(c, R_0) m ( c , R 0 ) 的上界,我们给出了当质量 c c c 趋于零时 u c u_c u c 渐近行为的精确描述,即 [ p ∣ λ 3 ∣ 2 γ c ] 1 p − 2 u c ( x + y c 2 δ p γ c ) → W p i n H 1 ( R 3 ) f o r s o m e y c ∈ R 3 a s c → 0 + . {[\frac{{p|{\lambda _3}|}}{{2{\gamma _c}}}]^{\frac{1}{{p - 2}}}}{u_c}(\frac{{x + {y_c}}}{{\sqrt {2{\delta _p}{\gamma _c}} }}) \to {W_p}\;\;\;\;{\rm{in}}\;\;\;\;{H^1}({\mathbb{R}^3})\;\;\;\;{\rm{for some}}\;\;\;\;{y_c} \in {\mathbb{R}^3}\;\;\;\;{\rm{as}}\;\;\;\;c \to {0^ + }. [ 2 γ c p ∣ λ 3 ∣ ] p − 2 1 u c ( 2 δ p γ c x + y c ) → W p in H 1 ( R 3 ) forsome y c ∈ R 3 as c → 0 + .
引用
@article{arxiv.2011.00804,
title = {Ground states for 3D dipolar Bose-Einstein condensate involving quantum fluctuations and three-body losses},
author = {Xiao Luo and Tao Yang},
journal= {arXiv preprint arXiv:2011.00804},
year = {2020}
}