We show that if the outermost waveguide of the binary waveguide array hosts the intense component of the truncated Dirac soliton, then Dirac soliton will be repeatedly bent towards the binary waveguide array edge. In the contrast, if the outermost waveguide of the binary waveguide array hosts the weak component of the truncated Dirac soliton, then Dirac soliton will be pushed away from the binary waveguide array edge. To the best of our knowledge, these unique features have not been found in any other systems. | Communications in Physics, Vol. 27, No. 3 (2017), pp. 205-214 DOI: EDGE EFFECTS OF TRUNCATED DIRAC SOLITONS IN BINARY WAVEGUIDE ARRAYS TRAN XUAN TRUONG † , NGUYEN MINH HUE AND PHUNG DINH HOAT Department of Physics, Le Quy Don University, 236 Hoang Quoc Viet, Hanoi, Vietnam † E-mail: tranxtr@ Received 05 September 2017 Accepted for publication 26 September 2017 Published 31 September 2017 Abstract. We investigate the edge effects of the optical analogue of the quantum relativistic Dirac solitons in binary waveguide arrays with Kerr nonlinearity when one tail of the Dirac soliton is truncated. We show that if the outermost waveguide of the binary waveguide array hosts the intense component of the truncated Dirac soliton, then Dirac soliton will be repeatedly bent towards the binary waveguide array edge. In the contrast, if the outermost waveguide of the binary waveguide array hosts the weak component of the truncated Dirac soliton, then Dirac soliton will be pushed away from the binary waveguide array edge. To the best of our knowledge, these unique features have not been found in any other systems. Keywords: nonlinear optics, binary waveguide array, Dirac soliton. Classification numbers: , , . I. INTRODUCTION Waveguide arrays (WAs) have attracted great attention because they can be used to simulate the evolution of a non-relativistic quantum mechanical particle in a periodic potential [1, 2]. Many fundamental phenomena in non-relativistic classical and quantum mechanics such as Bloch oscillations [3, 4] and Zener tunneling [5, 6] have been investigated by using WAs. Recently, it was shown that several important nonlinear phenomena usually associated to fiber optics (such as the emission of resonant radiation from solitons and soliton self-wavenumber shift) can also take place in WAs, but in the spatial domain rather than in the temporal domain [7, 8]; and the supercontinuum in both frequency and wave