Phonon rogue waves in materials

The effect of phonons on a material’s properties is usually considered in the regime where their influence on the atomic structure is to generate small displacements from equilibrium as these configurations dominate the available phase space.  However, rare events in which phonons combine to generate larger deviations from equilibrium may have more impact on material properties than their share of the phase space would suggest.  We calculate the rate at which these phonon rogue waves are expected to arise under the model that individual phonons are independent and uncorrelated.  We apply these statistics to both phonon based transient defects and phonon generated Ampere field fluctuations.  The rate of transient defect generation provides a correction to electron mobility calculations in graphene^[1], while we use the Ampere field fluctuations to treat the spin-phonon interaction in Ge quantum dots, GaAs, InAs, and InSb more directly than in the previously utilized Redfield theory^[2].

 

[1]  Brooks, Andrew and Jiang, Tao and Liu, Shuanglong and Le, Duy and Rahman, Talat S. and Cheng, Hai-Ping and Zhang, Xiao-Guang, “Modeling carrier mobility in graphene as a sensitive probe of molecular magnets,” Phys. Rev. B 103, 245423

[2]  Yue Yu, Xiaoliang Zhang, Sam Dillon, Jia Chen, Yiyuan Chen, Hai-Ping Cheng, Xiao-Guang Zhang, “Ampere field fluctuation from acoustic phonons as a possible source of spin decoherence,” Journal of Physics and Chemistry of Solids, 171, 111000