32 research outputs found
Scheme for generating entangled states of two field modes in a cavity
This paper considers a two-level atom interacting with two cavity modes with
equal frequencies. Applying a unitary transformation, the system reduces to the
analytically solvable Jaynes-Cummings model. For some particular field states,
coherent and squeezed states, the transformation between the two bare basis's,
related by the unitary transformation, becomes particularly simple. It is shown
how to generate, the highly non-classical, entangled coherent states of the two
modes, both in the zero and large detuning cases. An advantage with the zero
detuning case is that the preparation is deterministic and no atomic
measurement is needed. For the large detuning situation a measurement is
required, leaving the field in either of two orthogonal entangled coherent
states.Comment: Accepted in J. Mod. Opt.; 12 pages; Replaced with revised version.
Extended discussion of experimental realizations, earlier studies in the
field and on the frequency dependence in the adiabatic eliminatio
Quantum-over-classical Advantage in Solving Multiplayer Games
We study the applicability of quantum algorithms in computational game theory
and generalize some results related to Subtraction games, which are sometimes
referred to as one-heap Nim games.
In quantum game theory, a subset of Subtraction games became the first
explicitly defined class of zero-sum combinatorial games with provable
separation between quantum and classical complexity of solving them. For a
narrower subset of Subtraction games, an exact quantum sublinear algorithm is
known that surpasses all deterministic algorithms for finding solutions with
probability .
Typically, both Nim and Subtraction games are defined for only two players.
We extend some known results to games for three or more players, while
maintaining the same classical and quantum complexities:
and respectively
Dynamical behavior of atom–photon entanglement for a four-level atom near the band edge of a 3D-anisotropic photonic crystal
Journeys from quantum optics to quantum technology
Sir Peter Knight is a pioneer in quantum optics which has now grown to an important branch of modern physics to study the foundations and applications of quantum physics. He is leading an effort to develop new technologies from quantum mechanics. In this collection of essays, we recall the time we were working with him as a postdoc or a PhD student and look at how the time with him has influenced our research