7 papers · 1 filter
Parametrization of Quantum States and Channels
T. Constantinescu, V. Ramakrishna
In this manuscript, a parametrization of positive matrices together with some of its many applications in quantum information theory is given.
Note on purifications of a qubit
Tiberiu Constantinescu, Viswanath Ramakrishna
This work provides a parametrization of the set of purifications of a 2x2 mixed state, and joint purifications (if any) of a given pair of mixed 2x2 states. The former is parametri…
Control of Switched Networks via Quantum Methods
K. L. Flores, V. Ramakrishna
We illustrate a technique for specifying piecewise constant controls for classes of switched electrical networks, typically used in converting power in a dc-dc converter. This proc…
Note on the Controllability of Molecular Systems
V. Ramakrishna
The reachable set for a finite dimensional quantum system is shown to be the orbit of the group corresponding to the internal and control Hamiltonians, even if this group is not co…
Comments on "Quantum Control by Decompositions of SU(2)"
V. Ramakrishna
The purpose of the paper is to point out some typos and to observe that the main result of V. Ramakrishna, K. Flores, H. Rabitz and R. J. Ober, Phys. Rev. A Volume 62, 054309, 2000…
Quantum control using sequences of simple control pulses
S. G. Schirmer, A. D. Greentree, V. Ramakrishna +1
Structured decompositions of a desired unitary operator are employed to derive control schemes that achieve certain control objectives for finite-level quantum systems using only s…