1. Department of Physics, Renmin University of China, Beijing 100872, China 2. Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, Renmin University of China, Beijing 100872, China
We study the impurity problem in a Fermi gas of 173Yb atoms near an orbital Feshbach resonance (OFR), where a single moving particle in the 3P0 state interacts with two background Fermi seas of particles in different nuclear states of the ground 1S0 manifold. By employing wave function ansatz to molecule and polaron states, we investigate various properties of the molecule, the attractive polaron, and the repulsive polaron states. In comparison to the case where only one Fermi sea is populated, we find that the presence of an additional Fermi sea acts as an energy shift between the two channels of the OFR. In addition, quantum fluctuations near the Fermi level can also induce sizable effects to various properties of the attractive and repulsive polarons.
G. Pagano, M. Mancini, G. Cappellini, L. Livi, C. Sias, J. Catani, M. Inguscio, and L. Fallani, Strongly interacting gas of two-electron fermions at an orbital Feshbach resonance, Phys. Rev. Lett. 115(26), 265301 (2015) https://doi.org/10.1103/PhysRevLett.115.265301
3
M. Höfer, L. Riegger, F. Scazza, C. Hofrichter, D. R. Fernandes, M. M. Parish, J. Levinsen, I. Bloch, and S. Fölling, Observation of an orbital interaction-induced Feshbach resonance in Yb173, Phys. Rev. Lett. 115(26), 265302 (2015) https://doi.org/10.1103/PhysRevLett.115.265302
4
Y. Cheng, R. Zhang, and P. Zhang, Orbital Feshbach resonances with a small energy gap between open and closed channels, Phys. Rev. A 93(4), 042708 (2016) https://doi.org/10.1103/PhysRevA.93.042708
5
T.-S. Deng, W. Zhang, and W. Yi, Tuning Feshbach resonances in cold atomic gases with interchannel coupling, Phys. Rev. A 96, 050701(R) (2017)
6
M. Iskin, Two-band superfluidity and intrinsic Josephson effect in alkaline-earth-metal Fermi gases across an orbital Feshbach resonance, Phys. Rev. A 94, 011604(R) (2016)
J. Xu, R. Zhang, Y. Cheng, P. Zhang, R. Qi, and H. Zhai, Reaching a Fermi-superfluid state near an orbital Feshbach resonance, Phys. Rev. A 94(3), 033609 (2016) https://doi.org/10.1103/PhysRevA.94.033609
9
L. He, J. Wang, S. G. Peng, X. J. Liu, and H. Hu, Strongly correlated Fermi superfluid near an orbital Feshbach resonance: Stability, equation of state, and Leggett mode, Phys. Rev. A 94(4), 043624 (2016) https://doi.org/10.1103/PhysRevA.94.043624
10
Y.-C. Zhang, S. Ding, and S. Zhang, Collective modes in a two-band superfluid of ultracold alkaline-earth-metal atoms close to an orbital Feshbach resonance, Phys. Rev. A 95, 041603(R) (2017)
11
S. Wang, J. S. Pan, X. Cui, W. Zhang, and W. Yi, Topological Fulde-Ferrell states in alkaline-earth-metallike atoms near an orbital Feshbach resonance, Phys. Rev. A 95(4), 043634 (2017) https://doi.org/10.1103/PhysRevA.95.043634
12
Y. Cheng, R. Zhang, and P. Zhang, Quantum defect theory for the orbital Feshbach resonance, Phys. Rev. A 95(1), 013624 (2017) https://doi.org/10.1103/PhysRevA.95.013624
13
J. G. Chen, T. S. Deng, W. Yi, and W. Zhang, Polarons and molecules in a Fermi gas with orbital Feshbach resonance, Phys. Rev. A 94(5), 053627 (2016) https://doi.org/10.1103/PhysRevA.94.053627
14
J. Xu and R. Qi, Polaronic and dressed molecular states in orbital Feshbach resonances, arXiv: 1710.00785 (2017)
15
T. S. Deng, Z. C. Lu, Y. R. Shi, J. G. Chen, W. Zhang, and W. Yi, Repulsive polarons in alkaline-earth-metallike atoms across an orbital Feshbach resonance, Phys. Rev. A 97(1), 013635 (2018) https://doi.org/10.1103/PhysRevA.97.013635
16
F. Chevy, Universal phase diagram of a strongly interacting Fermi gas with unbalanced spin populations, Phys. Rev. A 74(6), 063628 (2006) https://doi.org/10.1103/PhysRevA.74.063628
17
R. Combescot, A. Recati, C. Lobo, and F. Chevy, Normal state of highly polarized Fermi gases: Simple manybody approaches, Phys. Rev. Lett. 98(18), 180402 (2007) https://doi.org/10.1103/PhysRevLett.98.180402
18
M. Punk, P. T. Dumitrescu, and W. Zwerger, Polaronto- molecule transition in a strongly imbalanced Fermi gas, Phys. Rev. A 80(5), 053605 (2009) https://doi.org/10.1103/PhysRevA.80.053605
19
S. Zöllner, G. M. Bruun, and C. J. Pethick, Polarons and molecules in a two-dimensional Fermi gas, Phys. Rev. A 83, 021603(R) (2011)
20
M. Klawunn and A. Recati, Fermi polaron in two dimensions: Importance of the two-body bound state, Phys. Rev. A 84(3), 033607 (2011) https://doi.org/10.1103/PhysRevA.84.033607
21
M. M. Parish, Polaron-molecule transitions in a twodimensional Fermi gas, Phys. Rev. A 83, 051603(R) (2011)
22
R. Schmidt, and T. Enss, Excitation spectra and RF response near the polaron-to-molecule transition from the functional renormalization group, Phys. Rev. A 83(6), 063620 (2011) https://doi.org/10.1103/PhysRevA.83.063620
23
X. W. Guan, Polaron, molecule and pairing in onedimensional spin-1/2 Fermi gas with an attractive deltafunction interaction, Front. Phys. 7(1), 8 (2012) https://doi.org/10.1007/s11467-011-0213-0
24
C. Trefzger, and Y. Castin, Impurity in a Fermi sea on a narrow Feshbach resonance: A variational study of the polaronic and dimeronic branches, Phys. Rev. A 85(5), 053612 (2012) https://doi.org/10.1103/PhysRevA.85.053612
25
M. Koschorreck, D. Pertot, E. Vogt, B. Fröhlich, M. Feld, and M. Köhl, Attractive and repulsive Fermi polarons in two dimensions, Nature 485(7400), 619 (2012) https://doi.org/10.1038/nature11151
26
P. Massignan, M. Zaccanti, and G. Bruun, Polarons, dressed molecules and itinerant ferromagnetism in ultracold Fermi gases, Rep. Prog. Phys. 77(3), 034401 (2014) https://doi.org/10.1088/0034-4885/77/3/034401
27
R. Schmidt, M. Knap, D. A. Ivanov, J. S. You, M. Cetina, and E. Demler, Universal many-body response of heavy impurities coupled to a Fermi sea: A review of recent progress, Rep. Prog. Phys. 81(2), 024401 (2018) https://doi.org/10.1088/1361-6633/aa9593
28
P. Massignan and G. M. Bruun, Repulsive polarons and itinerant ferromagnetism in strongly polarized Fermi gases, Eur. Phys. J. D 65(1-2), 83 (2011) https://doi.org/10.1140/epjd/e2011-20084-5
29
P. Massignan, Z. Yu, and G. M. Bruun, Itinerant ferromagnetism in a polarized two-component Fermi gas, Phys. Rev. Lett. 110(23), 230401 (2013) https://doi.org/10.1103/PhysRevLett.110.230401
30
C. Kohstall, M. Zaccanti, M. Jag, A. Trenkwalder, P. Massignan, G. M. Bruun, F. Schreck, and R. Grimm, Metastability and coherence of repulsive polarons in a strongly interacting Fermi mixture, Nature 485(7400), 615 (2012) https://doi.org/10.1038/nature11065
31
X. Cui and H. Zhai, Stability of a fully magnetized ferromagnetic state in repulsively interacting ultracold Fermi gases, Phys. Rev. A 81, 041602(R) (2010)
32
S. Pilati, G. Bertaina, S. Giorgini, and M. Troyer, Itinerant ferromagnetism of a repulsive atomic Fermi gas: A quantum Monte Carlo study, Phys. Rev. Lett. 105(3), 030405 (2010) https://doi.org/10.1103/PhysRevLett.105.030405
33
M. Cetina, M. Jag, R. S. Lous, I. Fritsche, J. T. M. Waldraven, R. Grimm, J. Levinsen, M. M. Parish, R. Schmidt, M. Knap, and E. Demler, Ultrafast manybody interferometry of impurities coupled to a Fermi sea, Science 354(6308), 96 (2016) https://doi.org/10.1126/science.aaf5134
34
G. Valtolina, F. Scazza, A. Amico, A. Burchianti, A. Recati, T. Enss, M. Inguscio, M. Zaccanti, and G. Roati, Exploring the ferromagnetic behaviour of a repulsive Fermi gas through spin dynamics, Nat. Phys. 13(7), 704 (2017)
35
S. Mondal, D. Inotani, and Y. Ohashi, Closed-channel contribution in the BCS-BEC crossover regime of an ultracold Fermi gas with an orbital Feshbach resonance, arXiv: 1709.00154v1 (2017)
F. Scazza, G. Valtolina, P. Massignan, A. Recati, A. Amico, A. Burchianti, C. Fort, M. Inguscio, M. Zaccanti, and G. Roati, Repulsive Fermi polarons in a resonant mixture of ultracold Li6 atoms, Phys. Rev. Lett. 118(8), 083602 (2017) https://doi.org/10.1103/PhysRevLett.118.083602
