Nonreciprocal photon blockade in a spinning microwave magnomechanical system through kerr-magnon and optical parametric amplifier

TL;DR

This work tackles the problem of creating direction-dependent single-photon sources by realizing nonreciprocal unconventional photon blockade (UPB) in a spinning microwave magnomechanical cavity that combines Kerr-magnon nonlinearity and a degenerate optical parametric amplifier. By leveraging the Sagnac-Fizeau shift, the authors obtain opposite blockade behavior for CW and CCW driving, supported by analytical solutions in a truncated low-excitation subspace and full Lindblad master-equation simulations. The study maps out optimal detuning and nonlinear parameters, analyzes the impact of thermal noise and pure dephasing, and uses the Mandel $Q$ parameter and time-delay correlations to characterize nonclassicality and blockade dynamics. The results promise tunable, directionally selective single-photon sources with potential applications in integrated quantum photonics and magnomechanical platforms.

Abstract

Unconventional quantum antibunching, arising from quantum interference effects, represents a notable form of quantum correlation that has attracted significant attention for its ability to generate high-quality single-quantum sources. In this work, we propose a scheme to achieve and actively control strong photon blockade in a spinning microwave magnomechanical system by leveraging the combined nonlinear effects of Kerr-induced magnon interactions and an optical parametric amplifier. By exploiting the Sagnac-Fizeau shift, we establish nonreciprocal photon blockade and verify this effect through a combination of analytical modelling and numerical simulations. To gain intuitive insight into the underlying nonreciprocity, we approximate the equal-time second-order correlation function using the analytical solution of the Schrödinger equation. This analytical result is then compared with the full numerical solution derived from the Lindblad master equation. The influences of thermal noise, the probe field amplitude, and the magnetic-dipole coupling strength are investigated within the constraints of the weak-coupling regime. The system's nonclassicality is characterized using the Mandel parameter, complemented by an analysis of the time evolution of the second-order correlation function. Our work provides a pathway for realizing nonreciprocal photon blockade in a nonlinear spinning microwave magnomechanical system.

Figures (8)

• Figure 1: (a) The panel illustrates a spinning microwave magnetomechanical system, incorporating magnon squeezing. A spinning optical resonator (mode $\rm a$) is driven from either the left or the right side, generating a Sagnac-Fizeau shift ($\Delta_F$), where the sign corresponds to the drive direction ($\Delta_F \gtrless 0$). A bias magnetic field ${\rm H}$ fully magnetizes the YIG sphere, which supports the magnon mode ($m$) and the phonon mode ($b$). Crucially, the YIG sphere's rotation at angular frequency $\Delta_B$ induces an emergent magnetic field $\mathbf{H}$, which shifts the magnon mode frequency. (b) photons in the cavity couple to the magnons via the magnetic dipole interaction, while magnons couple to the phonons through the magnetostrictive effect, which functions similarly to radiation pressure.
• Figure 2: Plot numerical (Num) and analytical (Ana) of the equal-time second-order correlation function $g_{\rm a}^{(2)}(0)$ versus the normalized detuning $\Delta/\omega_{\rm b}$ for $|\Delta_{\rm F}|=0.5\gamma$ with $\lambda=\lambda_{opt}\approx (2.46, 2.46, 2.46~~{\rm and}~~2.47)\times 10^{-6}\omega_b$ in (a), (b), (c) and (d), respectively. See the text for value of other parameters.
• Figure 3: Plot numerical of the equal-time second-order correlation function $g_{\rm a}^{(2)}(0)$ versus [a] the normalized detuning $\Delta/\omega_{\rm d}$ for different values of $m_{th}$; [b] $m_{th}$ for different values of $\Delta_{\rm F}$ with $\lambda=\lambda_{opt}\approx 2.46\times 10^{-6}\omega_b$ and $\Delta=\Delta_{opt}\approx -0.68\omega_b$; and [c] the normalized $\Delta_F/\gamma$ and the normalized detuning $\Delta/\omega_{\rm d}$, where the white dotted line indicates the optimal parameter conditions for unconventional photon blockade (UPB). See the text for value of other parameters.
• Figure 4: Plot of the equal-time second-order correlation function $g_{\rm a}^{(2)}(0)$ parameter versus the normalized kerr magnon parameter $K/\gamma$ with $\lambda=\lambda_{opt}\approx 2.46\times 10^{-6}\omega_b$ and $\Delta=\Delta_{opt}=-0.68\omega_b$. Plot numerical of the $g_{\rm a}^{(2)}(0)$ as a function of the normalized detuning $\Delta/\omega_{b}$ and $K/\gamma$ with $\lambda=\lambda_{opt}\approx 2.46\times 10^{-6}\omega_b$, where the white dotted line indicates the optimal parameter conditions for unconventional photon blockade (UPB). See the text for value of other parameters.
• Figure 5: Plot of the equal-time second-order correlation function $g_{\rm a}^{(2)}(0)$ parameter versus $E/\gamma$ with $\lambda=\lambda_{opt}\approx 2.46\times 10^{-6}\omega_b$ and $\Delta=\Delta_{opt}=-0.68\omega_b$. Plot numerical of the $g_{\rm a}^{(2)}(0)$ as a function of the normalized detuning $\Delta/\omega_{b}$ and $E/\gamma$ with $\lambda=\lambda_{opt}\approx 2.46\times 10^{-6}\omega_b$, where the white dotted line indicates the optimal parameter conditions for unconventional photon blockade (UPB). See the text for value of other parameters.