Generation of long-lived $W$ states via reservoir engineering in dissipatively coupled systems

Abstract

Very recently, the dissipative coupling was discovered, which develops and broadens methods for controlling and utilizing light-matter interactions. Here, we propose a scheme to generate the tripartite W state in a dissipatively coupled system, where one qubit and two resonators simultaneously interact with a common reservoir. With appropriate parameters, we find the W state is a dark state of the system. By driving the qubit, the dissipatively coupled system will evolve from the ground state to the tripartite W state. Because the initial state is the ground state of the system and no measurement is required, our scheme is easy to implement in experiments. Moreover, the W state decouples from the common reservoir and thus has a very long lifetime. This scheme is applicable to a wide class of dissipatively coupled systems, and we specifically illustrate how to prepare the W state in a hybrid qubit-photon-magnon system by using this scheme.

Interconversion of $W$ and Greenberger-Horne-Zeilinger states for Ising-coupled qubits with transverse global control

“…In particular, in the three-qubit case W and GHZ are the only two subclasses of states with genuine tripartite entanglement [6]. Both classes have proven useful in diverse QIP contexts [7][8][9][10][11], which was the primary motivation behind a large number of proposals for the efficient preparation of W [12][13][14][15][16][17][18][19][20][21] and GHZ states [22][23][24][25][26][27][28][29][30] in various physical systems.…”

Detection sensitivity enhancement of magnon Kerr nonlinearity in cavity magnonics induced by coherent perfect absorption

“…Besides the 3D microwave cavity, other geometric cavities, including one-dimensional Fabry-Perot-like cavity [8], superconducting coplanar waveguide resonator [9][10][11], cross-line microwave circuit [12] and split-ring resonator [13], have been fabricated in experiments. Up to now, various exotic phenomena have been extensively investigated in cavity-magnon systems, such as magnon dark modes [14], manipulating spin currents [15,16], steady-state magnon-photon entanglement [17], magnon blockade [18][19][20], non-Hermitian physics [21][22][23], cooperative polariton dynamics [24], quantum states of magnons [25][26][27][28], and microwave-to-optical transduction [29,30]. Mediated by the traveling-wave modes in the open waveguide, the dissipative coupling between magnons and microwave photons have been demonstrated experimentally [8].…”