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Keldysh field theory of dynamical exciton condensation transitions in nonequilibrium electron-hole bilayers (2311.04074v3)
Published 7 Nov 2023 in cond-mat.mes-hall and cond-mat.str-el
Abstract: Recent experiments have realized steady-state electrical injection of interlayer excitons in electron-hole bilayers subject to a large bias voltage. In the ideal case in which interlayer tunneling is negligibly weak, the system is in quasi-equilibrium with a reduced effective band gap. Interlayer tunneling introduces a current and drives the system out of equilibrium. In this work we derive a nonequilibrium field theory description of interlayer excitons in biased electron-hole bilayers. In the large bias limit, we find that p-wave interlayer tunneling reduces the effective band gap and increases the effective temperature for intervalley excitons. We discuss possible experimental implications for InAs/GaSb quantum wells and transition metal dichalcogenide bilayers.
- J. M. Blatt, K. Böer, and W. Brandt, Bose-Einstein condensation of excitons, Physical Review 126, 1691 (1962).
- L. Keldysh and A. Kozlov, Collective properties of excitons in semiconductors, Sov. Phys. JETP 27, 521 (1968).
- Y. E. Lozovik and V. Yudson, A new mechanism for superconductivity: pairing between spatially separated electrons and holes, Zh. Eksp. Teor. Fiz 71, 738 (1976).
- M. M. Fogler and F. Wilczek, Josephson effect without superconductivity: realization in quantum hall bilayers, Physical Review Letters 86, 1833 (2001).
- J. Eisenstein and A. MacDonald, Bose-Einstein condensation of excitons in bilayer electron systems, Nature 432, 691 (2004).
- J. Eisenstein, Exciton condensation in bilayer quantum hall systems, Annu. Rev. Condens. Matter Phys. 5, 159 (2014).
- E. Tutuc, M. Shayegan, and D. Huse, Counterflow measurements in strongly correlated GaAs hole bilayers: evidence for electron-hole pairing, Physical review letters 93, 036802 (2004).
- A. Perali, D. Neilson, and A. R. Hamilton, High-temperature superfluidity in double-bilayer graphene, Physical review letters 110, 146803 (2013).
- M. Fogler, L. Butov, and K. Novoselov, High-temperature superfluidity with indirect excitons in van der Waals heterostructures, Nature communications 5, 1 (2014).
- F.-C. Wu, F. Xue, and A. MacDonald, Theory of two-dimensional spatially indirect equilibrium exciton condensates, Physical Review B 92, 165121 (2015).
- Y. Zeng, N. Wei, and A. H. MacDonald, Layer pseudospin magnetism in a transition metal dichalcogenide double-moiré system, Physical Review B 106, 165105 (2022a).
- K. F. Mak and J. Shan, Photonics and optoelectronics of 2d semiconductor transition metal dichalcogenides, Nature Photonics 10, 216 (2016).
- K. F. Mak and J. Shan, Opportunities and challenges of interlayer exciton control and manipulation, Nature nanotechnology 13, 974 (2018).
- Y. Zeng and A. MacDonald, Electrically controlled two-dimensional electron-hole fluids, Physical Review B 102, 085154 (2020).
- M. Xie and A. H. MacDonald, Electrical reservoirs for bilayer excitons, Phys. Rev. Lett. 121, 067702 (2018).
- L. V. Keldysh et al., Diagram technique for nonequilibrium processes, Sov. Phys. JETP 20, 1018 (1965).
- A. Kamenev, Field theory of non-equilibrium systems (Cambridge University Press, 2023).
- A. Altland and B. D. Simons, Condensed matter field theory (Cambridge university press, 2010).
- F. Xue and A. H. MacDonald, Time-reversal symmetry-breaking nematic insulators near quantum spin hall phase transitions, Physical Review Letters 120, 186802 (2018).
- Y. Zeng, F. Xue, and A. H. MacDonald, In-plane magnetic field induced density wave states near quantum spin hall phase transitions, Physical Review B 105, 125102 (2022b).
- M. F. Maghrebi and A. V. Gorshkov, Nonequilibrium many-body steady states via keldysh formalism, Physical Review B 93, 014307 (2016).
- K. Dunnett and M. Szymańska, Keldysh field theory for nonequilibrium condensation in a parametrically pumped polariton system, Physical Review B 93, 195306 (2016).
- A. Mitra, I. Aleiner, and A. Millis, Semiclassical analysis of the nonequilibrium local polaron, Physical review letters 94, 076404 (2005).
- J. M. Kosterlitz and D. J. Thouless, Ordering, metastability and phase transitions in two-dimensional systems, Journal of Physics C: Solid State Physics 6, 1181 (1973).
- A. Filinov, N. Prokof’Ev, and M. Bonitz, Berezinskii-Kosterlitz-Thouless transition in two-dimensional dipole systems, Physical review letters 105, 070401 (2010).
- R. Bistritzer and A. H. MacDonald, Moiré bands in twisted double-layer graphene, Proceedings of the National Academy of Sciences 108, 12233 (2011).
- F. Wu, T. Lovorn, and A. MacDonald, Theory of optical absorption by interlayer excitons in transition metal dichalcogenide heterobilayers, Physical Review B 97, 035306 (2018).