Nonlinear excitations in a magnetic quantum dot array with biquadratic interaction

Magnetic quantum dots are promising candidates for applications like quantum computers and data storage devices. We investigate the nonlinear excitations in a coupled magnetic quantum dot array with biquadratic interaction. Starting from the Heisenberg Hamiltonian, which gives the interactive energy, we derive the equations of motion in the semiclassical limit using Glauber's coherent state ansatz combined with the Holstein-Primakoff bosonic representation of spin operators. The dynamics is found to be governed by a generalized nonlinear Schrodinger equation in the continuum limit. In the lower order of the expansion parameters, the system admits soliton solutions.