Quantum Inf Process (2014) 13:2017–2038 DOI 10.1007/s11128-014-0794-y Entanglement dynamics in two-parameter qubit–qutrit states under Dzyaloshinskii–Moriya interaction Kapil K. Sharma · S. N. Pandey Received: 3 March 2014 / Accepted: 4 July 2014 / Published online: 23 July 2014 © Springer Science+Business Media New York 2014 Abstract We study entanglement dynamics in two-parameter qubit–qutrit states under the influence of Dzyaloshisnhkii–Moriya (DM) interaction. Our system con- sists of a qubit–qutrit pair as a closed system initially in two-parameter class of states, and one environmental qubit interacts with the qutrit of the closed system via DM interaction. We divide our analysis into two cases. In the first case, we study the entan- glement dynamics in separable region, and in the second case we study the same in non-separable region. The DM interaction produces the entanglement in separable region with entanglement sudden death (ESD) and some states in this region remain unaffected by the same. In non-separable region, all the states are affected by DM interaction. The DM interaction excites the entanglement but does not produce ESD in this region. We observed that probability amplitude of environmental qubit does not affect the entanglement in two-parameter qubit–qutrit states in both the regions. Keywords Two-parameter qubit–qutrit states · Dzyaloshinskii-Moriya interaction · Separable region · Non-separable region · Entanglement sudden death · Probability amplitude 1 Introduction Entanglement is one of the key quantum correlations [1, 2], which is used for quantum technologies such as teleportation, quantum secure transmission of information, quan- tum games, quantum imaging [3–6]. The deep insights in entanglement for multipartite K. K. Sharma · S. N. Pandey (B ) Department of Physics, Motilal Nehru National Institute of Technology, Allahabad 211004, India e-mail: snp@mnnit.ac.in K. K. Sharma e-mail: scienceglobal@gmail.com 123