Exchange couplings and quantum phases in two dissimilar arrays of similar copper dinuclear units

Abstract

X-ray structure and EPR spectra of two dinuclear copper compounds allow us to study spin entanglement and quantum phase transitions. Their different 3D arrays and interdinuclear exchange paths produce important effects.

Symmetry-Induced Emergence of a Pseudo-Qutrit in the Dipolar Coupling of Two Qubits

“…It is worth noting that no qualitative difference in the results reported in this study would appear starting from a different choice of the form of matrix . We emphasize that, given a system of two dipolarly coupled distinguibisgable qubits acted upon by a uniform and static magnetic field, the control of the orientation of the binary system with respect to the laboratory frame is within the reach of the experimentalists [ 61 ]. Therefore, the emergence or disappearance of pseudo-qutrit quantum dynamics could be investigated experimentally.…”

“…A similar route has recently been used to investigate the dynamics of a pair [ 25 , 26 , 27 , 28 , 29 , 30 , 31 ] or a chain [ 32 , 33 ] of coupled spins (also greater than ) subjected to time-independent and time-dependent [ 34 , 35 , 36 ] external magnetic fields. Symmetry arguments have also been exploited to elegantly bring to light intriguing dynamic features of physical systems living in Hilbert spaces of infinite dimensions [ 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 ]. In Section 4 it is demonstrated that the time evolution of the two dipolarly coupled spins nests a qutrit subdynamics governed by a Hamiltonian model that is explicitly derived.…”