Zitterbewegung effect and quantum geometry in non-Hermitian exciton-polariton systems

In this work, we analytically derive a semi-classical equation of motion describing the Zitterbewegung effects arising in the dynamics of wavepackets in non-Hermitian systems. In Hermitian non-relativistic quantum systems, the Zitterbewegung effects can arise due to the spin precession and spin–orbit coupling. Interestingly, the spin dynamics in non-Hermitian systems is qualitatively different because of the effective nonlinear terms induced by the non-Hermitian part of the Hamiltonian. In this work, we show the effects from the non-Hermitian spin dynamics by generalizing the description of Zitterbewegung effects to non-Hermitian systems. We also uncover non-Hermitian correction to the group velocity, which can be expressed in terms of the non-Hermitian quantum metric tensor in the absence of out-of-plane effective field.