Cooperative Interaction between Two Self-Trapped Excitons

Ellen Roick, R. Gaethke, Peter Gürtler +1 more

E. B. Magnusson, Hugo Flayac, G. Malpuech +1 more

We analyze theoretically the role of the exciton-phonon interactions in phenomena related to the Josephson effect between two spatially separated exciton and exciton-polariton condensates. We consider the role of the dephasing introduced by phonons in such phenomena as Josephson tunneling, self-trapping and spontaneous polarization separation. In the regime of cw pumping we find a remarkable bistability effect arising from exciton-exciton interactions as well as regimes of self-sustained regular and chaotic oscillations.

Hermann Haken, J. Goll, Axel Schenzle

Alexander A. Zabolotskii

Exciton self-trapping in a molecular medium is considered within a self-consistent model taking into account the change in the dipole moment as a result of a displacement of molecules and the resonance interaction with an electromagnetic field. New mechanisms and specific features of the formation of localized structures in quasi-one-dimensional molecular structures are investigated. It is shown that the dependence of the dipole moment on molecular vibrations leads to new conditions for exciton self-trapping and intrinsic optical bistability, as well as for the formation of electromagnetically induced transparency. The theory proposed is used to explain the specific features of exciton self-trapping in a conjugated polymer and J aggregates of dyes under the action of an external laser field.

J. J. Hopfield

Longlong Zhang, Hongwei 宏伟 Li 李, Zhenyu 振宇 Xu 徐 +3 more

Abstract We theoretically propose a scheme for the coherent manipulation of a single qubit, which is constructed using the self-trapped triplet exciton (STTE) in FM/polymer/FM sandwich. The STTE serves as a quantum dot, comprising two degenerate triplet states with opposite magnetizations, thereby forming the qubit’s subspace. We demonstrate that the spin state of this qubit can be coherently manipulated by applying an external circularly polarized laser (CPL) to form the Floquet state. The manipulation exhibits significant helicity dependence: when the CPL’s angular momentum is antiparallel to the STTE’s spin orientation, the STTE undergoes Rabi oscillations between the |↑↑〉 and |↓↓〉 state, corresponding to a π -rotation around the x -axis on the Bloch sphere. Conversely, when the CPL’s angular momentum is parallel to the STTE’s spin orientation, the STTE remains unresponsive to the CPL. Two-axis coherent control of the STTE qubit can be potentially realized by additionally applying a static magnetic field B z . Our work provides a theoretical perspective for realizing the coherent manipulation of a qubit in organic devices.