Fabian Grusdt, Kushal Seetharam, Yulia Shchadilova, and Eugene Demler. Submitted. “Strong coupling Bose polarons out of equilibrium: Dynamical RG approach.” arXiv:1711.03478. Publisher's VersionAbstract
When a mobile impurity interacts with a surrounding bath of bosons, it forms a polaron. Numerous methods have been developed to calculate how the energy and the effective mass of the polaron are renormalized by the medium for equilibrium situations. Here we address the much less studied non-equilibrium regime and investigate how polarons form dynamically in time. To this end, we develop a time-dependent renormalization group approach which allows calculations of all dynamical properties of the system and takes into account the effects of quantum fluctuations in the polaron cloud. We apply this method to calculate trajectories of polarons following a sudden quench of the impurity-boson interaction strength, revealing how the polaronic cloud around the impurity forms in time. Such trajectories provide additional information about the polaron’s properties which are challenging to extract directly from the spectral function measured experimentally using ultracold atoms. At strong couplings, our calculations predict the appearance of trajectories where the impurity wavers back at intermediate times as a result of quantum fluctuations. Our method is applicable to a broader class of non-equilibrium problems. As a check, we also apply it to calculate the spectral function and find good agreement with experimental results. At very strong couplings, we predict that quantum fluctuations lead to the appearance of a dark continuum with strongly suppressed spectral weight at low energies. While our calculations start from an effective Fröhlich Hamiltonian describing impurities in a three-dimensional Bose-Einstein condensate, we also calculate the effects of additional terms in the Hamiltonian beyond the Fröhlich paradigm. We demonstrate that the main effect of these additional terms on the attractive side of a Feshbach resonance is to renormalize the coupling strength of the effective Fröhlich model.
Sarang Gopalakrishnan, Yulia E Shchadilova, and Eugene Demler. 2017. “Intertwined and vestigial order with ultracold atoms in multiple cavity modes.” Physical Review A, 96, 6, Pp. 063828. Publisher's Version
F Grusdt, R Schmidt, YE Shchadilova, and E. Demler. 2017. “Strong-coupling Bose polarons in a Bose-Einstein condensate.” Physical Review A, 96, 1, Pp. 013607. Publisher's Version
Yulia Shchadilova. 2017. “Viewpoint: A New Angle on Quantum Impurities.” Physics, 10, Pp. 20. Publisher's Version
Emanuele G Dalla Torre, Yulia Shchadilova, Eli Y Wilner, Mikhail D Lukin, and Eugene Demler. 2016. “Dicke phase transition without total spin conservation.” Physical Review A, 94, 6, Pp. 061802. Publisher's Version
Yulia E Shchadilova, Fabian Grusdt, Alexey N Rubtsov, and Eugene Demler. 2016. “Polaronic mass renormalization of impurities in Bose-Einstein condensates: Correlated Gaussian-wave-function approach.” Physical Review A, 93, 4, Pp. 043606. Publisher's Version
Yulia E Shchadilova, Richard Schmidt, Fabian Grusdt, and Eugene Demler. 2016. “Quantum dynamics of ultracold Bose polarons.” Physical Review Letters, 117, 11, Pp. 113002. Publisher's Version
Alexey M Shakirov, Yulia E Shchadilova, and Alexey N Rubtsov. 2016. “Quantum statistical ensemble for emissive correlated systems.” Physical Review E, 93, 6, Pp. 062122. Publisher's Version
Alexey M Shakirov, Yulia E Shchadilova, Alexey N Rubtsov, and Pedro Ribeiro. 2016. “Role of coherence in transport through engineered atomic spin devices.” Physical Review B, 94, 22, Pp. 224425. Publisher's Version
Dmitry V Chichinadze, Pedro Ribeiro, Yulia E Shchadilova, and Alexey N Rubtsov. 2016. “Transient phases and dynamical transitions in the post-quench evolution of the generalized Bose-Anderson model.” Physical Review B, 94, 5, Pp. 054301. Publisher's Version
Alexey M Shakirov, Sergey V Tsibulsky, Andrey E Antipov, Yulia E Shchadilova, and Alexey N Rubtsov. 2015. “Modeling the metastable dynamics of correlated structures.” Scientific reports, 5, Pp. 08005. Publisher's Version
F Grusdt, YE Shchadilova, AN Rubtsov, and E. Demler. 2015. “Renormalization group approach to the Fröhlich polaron model: application to impurity-BEC problem.” Scientific reports, 5, Pp. 12124 . Publisher's Version
Yulia E. Shchadilova, Sergei G. Tikhodeev, Magnus Paulsson, and Hiromu Ueba. 2014. “Isotope effect in acetylene C2H2 and C2D2 rotations on Cu(001).” Physical Review B, 89, Pp. 165418. Publisher's Version
Yulia E Shchadilova, Pedro Ribeiro, and Masudul Haque. 2014. “Quantum quenches and work distributions in ultralow-density systems.” Physical review letters, 112, 7, Pp. 070601. Publisher's Version
Yulia E Shchadilova, Matthias Vojta, and Masudul Haque. 2014. “Single-impurity Kondo physics at extreme particle-hole asymmetry.” Physical Review B, 89, Pp. 104102. Publisher's Version
AK Fedorov, IL Kurbakov, YE Shchadilova, and Yu E Lozovik. 2014. “Two-dimensional Bose gas of tilted dipoles: Roton instability and condensate depletion.” Physical Review A, 90, 4, Pp. 043616. Publisher's Version
Yulia E Shchadilova, Sergei G Tikhodeev, Magnus Paulsson, and Hiromu Ueba. 2013. “Rotation of a single acetylene molecule on Cu (001) by tunneling electrons in STM.” Physical Review Letters, 111, 18, Pp. 186102. Publisher's Version
YE Shchadilova. 2009. “Energy distribution in strongly perturbed chaotic system.” Moscow University Physics Bulletin, 64, 6, Pp. 655–657.