Haozhen Situ

Dynamics of relative entropy of coherence under Markovian channels

We study the relative entropy of coherence under the effect of certain one-qubit channels that are Markovian and noisy. The cohering power and decohering power of phase damping, amplitude damping, flip and depolarizing channels are analytically calculated. For phase damping channel, the decohering power on the

Two-player conflicting interest Bayesian games and Bell nonlocality

x,\ y,

Simultaneous dense coding

x,y, and z bases is the same. The same phenomenon is observed for the flip and depolarizing channels. Further, we show that weak measurement and its reversal can be employed to suppress the decohering power of the amplitude damping channel.

Non-Markovian dynamics of quantum coherence of two-level system driven by classical field

We present a quantum approach to play asymmetric coordination games, which are more general than symmetric coordination games such as the Battle of the Sexes game, the Chicken game and the Hawk–Dove game. Our results show that quantum entanglement can help the players to coordinate their strategies.

Performance analysis of simultaneous dense coding protocol under decoherence

Nonlocality, one of the most remarkable aspects of quantum mechanics, is closely related to Bayesian game theory. Quantum mechanics can offer advantages to some Bayesian games, if the payoff functions are related to Bell inequalities in some way, most of these Bayesian games that have been discussed are common interest games. Recently, the first conflicting interest Bayesian game is proposed in Phys. Rev. Lett. 114, 020401 (2015). In the present paper, we present three new conflicting interest Bayesian games where quantum mechanics offers advantages. The first game is linked with Cereceda inequalities, the second game is linked with a generalized Bell inequality with three possible measurement outcomes, and the third game is linked with a generalized Bell inequality with three possible measurement settings.

Noise effects on conflicting interest quantum games with incomplete information

We use one of the influential quantum game models, the Marinatto–Weber model, to investigate quantum Bayesian game. We show that in a quantum Bayesian game which has more than one Nash equilibrium, one equilibrium stands out as the compelling solution, whereas two Nash equilibria seem equally compelling in the classical Bayesian game.

Enhancing user privacy in SARG04-based private database query protocols

We present a dense coding scheme between one sender and two receivers, which guarantees that the receivers simultaneously achieve their respective information. In our scheme, the sender first performs a locking operation to entangle the particles from two independent quantum entanglement channels, so that the receivers cannot achieve their information unless they collaborate to perform the unlocking operation. We also show that the quantum Fourier transform can act as the locking operator both in simultaneous dense coding and teleportation. Finally we compare simultaneous dense coding with quantum secret sharing of classical messages.

Secure N-dimensional simultaneous dense coding and applications

In this paper, we study the quantum coherence dynamics of two-level atom system embedded in non-Markovian reservoir in the presence of classical driving field. We analyze the influence of memory effects, classical driving, and detuning on the quantum coherence. It is found that the quantum coherence has different behaviors in resonant case and non-resonant case. In the resonant case, in stark contrast with previous results, the strength of classical driving plays a negative effect on quantum coherence, while detuning parameter has the opposite effect. However, in non-resonant case through a long time, classical driving and detuning parameter have a different influence on quantum coherence compared with resonant case. Due to the memory effect of environment, in comparison with Markovian regime, quantum coherence presents vibrational variations in non-Markovian regime. In the resonant case, all quantum coherence converges to a fixed maximum value; in the non-resonant case, quantum coherence evolves to different stable values. For zero-coherence initial states, quantum coherence can be generated with evolution time. Our discussions and results should be helpful in manipulating and preserving the quantum coherence in dissipative environment with classical driving field.