211 citations · 1.2k across the 74 of their papers we have counts for
5 papers · 1 filter
Lower Bound on the Chromatic Number by Spectra of Weighted Adjacency Matrices
Pawel Wocjan, Dominik Janzing, Thomas Beth
A lower bound on the chromatic number of a graph is derived by majorization of spectra of weighted adjacency matrices. These matrices are given by Hadamard products of the adjacenc…
Simulating Hamiltonians in Quantum Networks: Efficient Schemes and Complexity Bounds
Pawel Wocjan, Martin Roetteler, Dominik Janzing +1
We address the problem of simulating pair-interaction Hamiltonians in n node quantum networks where the subsystems have arbitrary, possibly different, dimensions. We show that any…
Universal Simulation of Hamiltonians Using a Finite Set of Control Operations
Pawel Wocjan, Martin Roetteler, Dominik Janzing +1
Any quantum system with a non-trivial Hamiltonian is able to simulate any other Hamiltonian evolution provided that a sufficiently large group of unitary control operations is avai…
Simulating Arbitrary Pair-Interactions by a Given Hamiltonian: Graph-Theoretical Bounds on the Time Complexity
P. Wocjan, D. Janzing, Th. Beth
We use an n-spin system with permutation symmetric zz-interaction for simulating arbitrary pair-interaction Hamiltonians. The calculation of the required time overhead is mathemati…
Complexity of decoupling and time-reversal for n spins with pair-interactions: Arrow of time in quantum control
Dominik Janzing, Pawel Wocjan, Thomas Beth
Well-known Nuclear Magnetic Resonance experiments show that the time evolution according to (truncated) dipole-dipole interactions between n spins can be inverted by simple pulse s…