392 citations · 1.3k across the 26 of their papers we have counts for
26 papers
A new local invariant for quantum gates
Laura Koponen, Ville Bergholm, Martti M. Salomaa
In this paper we study the properties of two-qubit gates. We review the most common parameterizations for the local equivalence classes of two-qubit gates and the connections betwe…
Collapse and revival of excitations in Bose-Einstein condensates
M. Mottonen, S. M. M. Virtanen, M. M. Salomaa
We study the energies and decay of elementary excitations in weakly interacting Bose-Einstein condensates within a finite-temperature gapless second-order theory. The energy shifts…
Quantum circuits with uniformly controlled one-qubit gates
Ville Bergholm, Juha J. Vartiainen, Mikko Mottonen +1
Uniformly controlled one-qubit gates are quantum gates which can be represented as direct sums of two-dimensional unitary operators acting on a single qubit. We present a quantum g…
Quantum Numbers for Excitations of Bose-Einstein Condensates in 1D Optical Lattices
Tomoya Isoshima, Martti M. Salomaa
The excitation spectrum and the band structure of a Bose-Einstein condensate in a periodic potential are investigated. Analyses within full 3D systems, finite 1D systems, and ideal…
Transformation of quantum states using uniformly controlled rotations
Mikko Mottonen, Juha J. Vartiainen, Ville Bergholm +1
We consider a unitary transformation which maps any given state of an -qubit quantum register into another one. This transformation has applications in the initialization of a q…
Quantum Circuits for General Multiqubit Gates
Mikko Mottonen, Juha J. Vartiainen, Ville Bergholm +1
We consider a generic elementary gate sequence which is needed to implement a general quantum gate acting on n qubits -- a unitary transformation with 4^n degrees of freedom. For s…