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多体系统的非平衡动力学演化是当前物理学中最具挑战性的问题之一. 超冷量子费米原子气体具有较强的可控性, 是研究多体非平衡动力学的理想系统, 可以用来模拟和理解大爆炸后的早期宇宙、重离子碰撞中产生的夸克-胶子以及核物理等动力学. 一般多体系统演化是非常复杂的, 往往需要利用对称性来研究. 利用Feshbach共振可以制备标度不变的费米原子气体: 无相互作用和幺正费米量子气体. 当远离平衡态时, 可利用普适的指数和函数来刻画, 其动力学可以通过对系统的时空演化进行标度变换来识别. 本文主要介绍近年来强相互作用超冷费米气体的膨胀动力学研究进展, 包括原子气体的各向异性展开、标度动力学和Efimovian膨胀动力学.
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关键词:
- 强相互作用超冷费米气体 /
- Feshbach共振 /
- 各向异性展开 /
- 标度不变性 /
- Efimovian膨胀动力学
The evolution of non-equilibrium dynamic for many-body systems is one of the most challenging problems in physics. Ultra-cold quantum atomic Fermi gas provide an test-bed for studying many-body non-equilibrium dynamics due to its high freedom of controllability, which can be used to simulate and understand the dynamics of the early universe after the Big Bang, quark-gluon produced in heavy ion collisions and nuclear physics. Generally, the evolution of many-body systems is very complex, and usually needs to be studied by symmetry. Feshbach resonance can be used to prepare scale invariant atomic Fermi gases: non-interacting and unitary Fermi gases. When far away from equilibrium state, universal exponents and functions can be used to characterize the dynamics of the system, which can be identified by scaling the temporal and spatial evolution of the system. In this review, the recent developments in the expansion dynamics of strongly interacting ultracold Fermi gases are introduced, including the anisotropic expansion of atomic gases, scaling dynamics and Efimovian expansion dynamics.-
Keywords:
- strongly-interacting ultracold Fermi gas /
- Feshbach resonance /
- anisotropic expansions /
- scale invariance /
- Efimovian expansion dynamics
[1] DeMarco B, Jin D S 1999 Science 285 1703Google Scholar
[2] O’Hara K M, Hemmer S L, Gehm M E, Granade S R, Thomas J E 2002 Science 298 2179Google Scholar
[3] Kinast J, Hemmer S L, Gehm M E, Turlapov A, Thomas J E 2004 Phys. Rev. Lett. 92 150402Google Scholar
[4] Bartenstein M, Altmeyer A, Riedl S, Jochim S, Chin C, Denschlag J H, Grimm R 2004 Phys. Rev. Lett. 92 203201Google Scholar
[5] Regal C A, Greiner M, Giorgini S, Holland M, Jin D S 2005 Phys. Rev. Lett. 95 250404Google Scholar
[6] Partridge G B, Strecker K E, Kamar R I, Jack M W, Hulet R G 2005 Phys. Rev. Lett. 95 020404Google Scholar
[7] Bartenstein M, Altmeyer A, Riedl S, Jochim S, Chin C, Denschlag J H, Grimm R 2004 Phys. Rev. Lett. 92 120401Google Scholar
[8] Zwierlein M W, Abo-Shaeer J R, Schirotzek A, Schunck C H, Ketterle W 2005 Nature 435 1047Google Scholar
[9] Liao Y, Rittner A, Paprotta T, Li W, Partridge G, Hulet R G, Baur S K, Mueller E J 2010 Nature 467 567Google Scholar
[10] Nguyen J H V, Luo D, Hulet R G 2017 Science 356 422Google Scholar
[11] Greif D, Parsons M F, Mazurenko A, Chiu C S, Blatt S, Huber F, Ji G, Greiner M 2016 Science 351 953Google Scholar
[12] Mazurenko A, Chiu C S, Ji G, Parsons M F, Kanasz-Nagy M, Schmidt R, Grusdt F, Demler E, Greif D, Greiner M 2017 Nature 545 462Google Scholar
[13] Hart R A, Duarte P M, Yang T, Liu X, Paiva T, Khatami E, Scalettar R T, Trivedi N, Huse D A, Hulet R G 2015 Nature 519 211Google Scholar
[14] Wang P, Yu Z, Fu Z, Miao J, Huang L, Chai S, Zhai H, Zhang J 2012 Phys. Rev. Lett. 109 095301Google Scholar
[15] Hoinka S, Lingham M, Delehaye M, Vale C J 2012 Phys. Rev. Lett. 109 050403Google Scholar
[16] Deng S, Shi Z, Diao P, Yu Q, Zhai H, Qi R, Wu H 2016 Science 353 371Google Scholar
[17] Lu M, Burdick N Q, Lev B L 2012 Phys. Rev. Lett. 108 215301Google Scholar
[18] Aikawa K, Frisch A, Mark M, Baier S, Grimm R, Ferlaino F 2014 Phys. Rev. Lett. 112 010404Google Scholar
[19] Ku M J, Sommer A T, Cheuk L W, Zwierlein M W 2012 Science 335 563Google Scholar
[20] Kinast J, Turlapov A, Thomas J E, Chen Q, Stajic J, Levin K 2005 Science 307 1296Google Scholar
[21] Nascimbéne S, Navon N, Jiang K J, Chevy F, Salomon C 2010 Nature 463 1057Google Scholar
[22] Clancy B, Luo L, Thomas J E 2007 Phys. Rev. Lett. 99 140401Google Scholar
[23] Kinnunen J, Rodríguez M, Törmä P 2004 Science 305 1131Google Scholar
[24] Chin C, Bartenstein M, Altmeyer A, Riedl S, Jochim S, Denschlag J H, Grimm R 2004 Science 305 1128Google Scholar
[25] Cao C, Elliott E, Joseph J, Wu H, Petricka J, Schäfer T, Thomas J E 2011 Science 331 58Google Scholar
[26] Bluhm M, Hou J, Schäfer T 2017 Phys. Rev. Lett. 119 065302Google Scholar
[27] Menotti C, Pedri P, Stringari S 2002 Phys. Rev. Lett. 89 250402Google Scholar
[28] Guéry-Odelin D 2002 Phys. Rev. A 66 033613Google Scholar
[29] Castin Y, Dum R 1996 Phys. Rev. Lett. 77 5315Google Scholar
[30] Kagan Y, Surkov E L, Shlyapnikov G 1996 Phys. Rev. A 54 R1753Google Scholar
[31] Ho T L 2004 Phys. Rev. Lett. 92 090402Google Scholar
[32] Makotyn P, Klauss C E, Goldberger D L, Cornell E A, Jin D S 2014 Nature Physics 10 116Google Scholar
[33] Bulgac A, Drut J E, Magierski P 2007 Phys. Rev. Lett. 99 120401Google Scholar
[34] Elliott E, Joseph J A, Thomas J E 2014 Phys. Rev. Lett. 112 040405Google Scholar
[35] Efimov V 1970 Phys. Lett. B 33 563Google Scholar
[36] Kraemer T, Mark M, Waldburger P, Danzl J G, Chin C, Engeser B, Lange A D, Pilch K, Jaakkola A, Nägerl H C, Grimm R 2006 Nature 440 315Google Scholar
[37] Braaten E, Hammer H W 2006 Phys. Rep. 428 259Google Scholar
[38] Braaten E, Hammer H W 2007 Ann. Phys. 322 120Google Scholar
[39] Gharashi S E, Blume D 2016 Phys. Rev. A 94 063639Google Scholar
[40] Riedl S, Sánchez Guajardo E R, Kohstall C, Altmeyer A, Wright M J, Denschlag J H, Grimm R, Bruun G M, Smith H 2008 Phys. Rev. A 78 053609Google Scholar
[41] Kinast J, Turlapov A, Thomas J E 2005 Phys. Rev. Lett. 94 170404Google Scholar
[42] Deng S, Diao P, Li F, Yu Q, Yu S, Wu H 2018 Phys. Rev. Lett. 120 125301Google Scholar
[43] Nishida, Moroz S, Son D T 2013 Phys. Rev. Lett. 110 235301Google Scholar
[44] Moroz S, Nishida Y 2014 Phys. Rev. A 90 063631Google Scholar
[45] Ulmanis J, Häfner S, Kuhnle E D, Weidemüller M 2016 Nat. Sci. Rev. 3 174Google Scholar
[46] Shi Z, Qi R, Zhai H, Yu Z 2017 Phys. Rev. A 96 050702Google Scholar
[47] Zhang L, Wen W, Ma X D, Wang Y 2018 Int. J. Mod. Phys. B 32 1850230Google Scholar
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图 1 (a)强相互作用超冷费米气体的各向异性膨胀吸收成像图; (b)原子团不同方向的非平衡动力学膨胀行为; (c)不同相互作用下原子团的纵横比大小演化图[2]
Fig. 1. (a)The absorption image of the anisotropic expansion dynamics in strongly interacting Fermi gas; (b) the non-equilibrium dynamical expansion behavior in different directions; (c) the evolution for the aspect ratio of the atomic cloud under different interaction regime[2].
图 4 Efimovian膨胀动力学示意图 (a), (b)原子气体所处谐振子阱频率的变化过程; (c)Efimovian 膨胀动力学的理论预测; (d), (e)分别代表无相互作用费米气体和强相互作用费米气体的Efimovian 膨胀动力学的实验观测结果[16]
Fig. 4. The Efimovian expansion dynamics: (a) and (b) are the evolution of the harmonic trap frequency; (c) the prediction of the Efimovian expansion dynamics; (d) and (e) are the experimental observation of the Efimovian expansion in non-interacting Fermi gas and unitary Fermi gas respectively[16].
图 5 Efimovian膨胀动力学的普适性 (a) Efimovian 膨胀动力学与原子间相互作用的关系; (b) Efimovian 膨胀动力学与原子数目、温度间的关系; (c), (d)无量纲化后的普适Efimovian 动力学膨胀图[16]
Fig. 5. The universality of the Efimovian expansion dynamics: (a) The Efimovian expansion with different interaction regime; (b) the Efimovian expansion with different atoms' number and temperature; (c) and (d) are the universal dimensionless Efimovian expansions[16].
图 6 超级Efimovian 膨胀动力学实验结果 (a)和(c)分别表示幺正费米气体和无相互作用费米气体的超级Efimov 动力学效应; (b)和(d)表示在时间双对数标度下相应原子团大小的振荡行为[42]
Fig. 6. The experimental observation of dynamical super Efimovian expansion. (a), (b) and (c), (d) are the mean axial cloud size versus the expansion time and the dimensionless axial mean square cloud size versus the dimensionless time in the unitary Fermi gas and ideal Fermi gas, respectively[42].
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[1] DeMarco B, Jin D S 1999 Science 285 1703Google Scholar
[2] O’Hara K M, Hemmer S L, Gehm M E, Granade S R, Thomas J E 2002 Science 298 2179Google Scholar
[3] Kinast J, Hemmer S L, Gehm M E, Turlapov A, Thomas J E 2004 Phys. Rev. Lett. 92 150402Google Scholar
[4] Bartenstein M, Altmeyer A, Riedl S, Jochim S, Chin C, Denschlag J H, Grimm R 2004 Phys. Rev. Lett. 92 203201Google Scholar
[5] Regal C A, Greiner M, Giorgini S, Holland M, Jin D S 2005 Phys. Rev. Lett. 95 250404Google Scholar
[6] Partridge G B, Strecker K E, Kamar R I, Jack M W, Hulet R G 2005 Phys. Rev. Lett. 95 020404Google Scholar
[7] Bartenstein M, Altmeyer A, Riedl S, Jochim S, Chin C, Denschlag J H, Grimm R 2004 Phys. Rev. Lett. 92 120401Google Scholar
[8] Zwierlein M W, Abo-Shaeer J R, Schirotzek A, Schunck C H, Ketterle W 2005 Nature 435 1047Google Scholar
[9] Liao Y, Rittner A, Paprotta T, Li W, Partridge G, Hulet R G, Baur S K, Mueller E J 2010 Nature 467 567Google Scholar
[10] Nguyen J H V, Luo D, Hulet R G 2017 Science 356 422Google Scholar
[11] Greif D, Parsons M F, Mazurenko A, Chiu C S, Blatt S, Huber F, Ji G, Greiner M 2016 Science 351 953Google Scholar
[12] Mazurenko A, Chiu C S, Ji G, Parsons M F, Kanasz-Nagy M, Schmidt R, Grusdt F, Demler E, Greif D, Greiner M 2017 Nature 545 462Google Scholar
[13] Hart R A, Duarte P M, Yang T, Liu X, Paiva T, Khatami E, Scalettar R T, Trivedi N, Huse D A, Hulet R G 2015 Nature 519 211Google Scholar
[14] Wang P, Yu Z, Fu Z, Miao J, Huang L, Chai S, Zhai H, Zhang J 2012 Phys. Rev. Lett. 109 095301Google Scholar
[15] Hoinka S, Lingham M, Delehaye M, Vale C J 2012 Phys. Rev. Lett. 109 050403Google Scholar
[16] Deng S, Shi Z, Diao P, Yu Q, Zhai H, Qi R, Wu H 2016 Science 353 371Google Scholar
[17] Lu M, Burdick N Q, Lev B L 2012 Phys. Rev. Lett. 108 215301Google Scholar
[18] Aikawa K, Frisch A, Mark M, Baier S, Grimm R, Ferlaino F 2014 Phys. Rev. Lett. 112 010404Google Scholar
[19] Ku M J, Sommer A T, Cheuk L W, Zwierlein M W 2012 Science 335 563Google Scholar
[20] Kinast J, Turlapov A, Thomas J E, Chen Q, Stajic J, Levin K 2005 Science 307 1296Google Scholar
[21] Nascimbéne S, Navon N, Jiang K J, Chevy F, Salomon C 2010 Nature 463 1057Google Scholar
[22] Clancy B, Luo L, Thomas J E 2007 Phys. Rev. Lett. 99 140401Google Scholar
[23] Kinnunen J, Rodríguez M, Törmä P 2004 Science 305 1131Google Scholar
[24] Chin C, Bartenstein M, Altmeyer A, Riedl S, Jochim S, Denschlag J H, Grimm R 2004 Science 305 1128Google Scholar
[25] Cao C, Elliott E, Joseph J, Wu H, Petricka J, Schäfer T, Thomas J E 2011 Science 331 58Google Scholar
[26] Bluhm M, Hou J, Schäfer T 2017 Phys. Rev. Lett. 119 065302Google Scholar
[27] Menotti C, Pedri P, Stringari S 2002 Phys. Rev. Lett. 89 250402Google Scholar
[28] Guéry-Odelin D 2002 Phys. Rev. A 66 033613Google Scholar
[29] Castin Y, Dum R 1996 Phys. Rev. Lett. 77 5315Google Scholar
[30] Kagan Y, Surkov E L, Shlyapnikov G 1996 Phys. Rev. A 54 R1753Google Scholar
[31] Ho T L 2004 Phys. Rev. Lett. 92 090402Google Scholar
[32] Makotyn P, Klauss C E, Goldberger D L, Cornell E A, Jin D S 2014 Nature Physics 10 116Google Scholar
[33] Bulgac A, Drut J E, Magierski P 2007 Phys. Rev. Lett. 99 120401Google Scholar
[34] Elliott E, Joseph J A, Thomas J E 2014 Phys. Rev. Lett. 112 040405Google Scholar
[35] Efimov V 1970 Phys. Lett. B 33 563Google Scholar
[36] Kraemer T, Mark M, Waldburger P, Danzl J G, Chin C, Engeser B, Lange A D, Pilch K, Jaakkola A, Nägerl H C, Grimm R 2006 Nature 440 315Google Scholar
[37] Braaten E, Hammer H W 2006 Phys. Rep. 428 259Google Scholar
[38] Braaten E, Hammer H W 2007 Ann. Phys. 322 120Google Scholar
[39] Gharashi S E, Blume D 2016 Phys. Rev. A 94 063639Google Scholar
[40] Riedl S, Sánchez Guajardo E R, Kohstall C, Altmeyer A, Wright M J, Denschlag J H, Grimm R, Bruun G M, Smith H 2008 Phys. Rev. A 78 053609Google Scholar
[41] Kinast J, Turlapov A, Thomas J E 2005 Phys. Rev. Lett. 94 170404Google Scholar
[42] Deng S, Diao P, Li F, Yu Q, Yu S, Wu H 2018 Phys. Rev. Lett. 120 125301Google Scholar
[43] Nishida, Moroz S, Son D T 2013 Phys. Rev. Lett. 110 235301Google Scholar
[44] Moroz S, Nishida Y 2014 Phys. Rev. A 90 063631Google Scholar
[45] Ulmanis J, Häfner S, Kuhnle E D, Weidemüller M 2016 Nat. Sci. Rev. 3 174Google Scholar
[46] Shi Z, Qi R, Zhai H, Yu Z 2017 Phys. Rev. A 96 050702Google Scholar
[47] Zhang L, Wen W, Ma X D, Wang Y 2018 Int. J. Mod. Phys. B 32 1850230Google Scholar
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