Showing papers by "Ying Wu published in 2018"
TL;DR: The existence of an equilibrium superradiant QPT in cavity and circuit QED systems is still debated, though, considering the no-go theorem as discussed by the authors, and the existence of a single-photon-triggered super-radiant quantum phase transition (QPT) is of fundamental interest, and has potential applications in modern quantum technology.
Abstract: The superradiant quantum phase transition (QPT) is of fundamental interest, and has potential applications in modern quantum technology. The existence of an equilibrium superradiant QPT in cavity and circuit QED systems is still debated, though, considering the no-go theorem. Combining cavity QED and optomechanics, the authors predict at thermal equilibrium a single-photon-triggered superradiant QPT that is immune to the no-go theorem. Being able to manipulate a QPT in this manner is expected to inspire both the creation of innovative photonic quantum devices and the exploration of single-photon quantum-criticality physics.
39 citations
TL;DR: In this article, a single photon can simultaneously excite two qubits without breaking the parity symmetry of system by properly encoding the excited states of qubits, and the optimal parameter regime for achieving high probability approaching one is identified in the case of ignoring the system dissipation.
Abstract: We investigate theoretically the model of two \qubits" system (one qubit having an auxiliary level) interacting with a single-mode resonator in the ultrastrong coupling regime. We show that a single photon could simultaneously excite two qubits without breaking the parity symmetry of system by properly encoding the excited states of qubits. The optimal parameter regime for achieving high probability approaching one is identified in the case of ignoring the system dissipation. Moreover, using experimentally feasible parameters, we also analyze the dissipation dynamics of the system, and present the realization of two-qubit excitation induced by single-photon. This work offers an alternative approach to realize the single-photon-induced two qubits excitation, which should advance the development of single-photon quantum technologies and have potential applications in quantum information science.
2 citations
TL;DR: In this paper, a hybrid quantum model combining cavity QED and optomechanics is proposed, which allows the occurrence of equilibrium superradiant quantum phase transition (QPT) triggered by a single photon.
Abstract: We propose a hybrid quantum model combining cavity QED and optomechanics, which allows the occurrence of equilibrium superradiant quantum phase transition (QPT) triggered by a single photon. This single-photon-triggered QPT exists both in the cases of ignoring and including the so-called $A^2$ term, i.e., it is immune to the no-go theorem. It originally comes from the photon-dependent quantum criticality featured by the proposed hybrid quantum model. Moreover, a reversed superradiant QPT is induced by the competition between the introduced $A^2$ term and the optomechanical interaction. This work offers an approach to manipulate QPT with a single photon, which should inspire the exploration of single-photon quantum-criticality physics and the engineering of new single-photon quantum devices.