Frequency Conversion Characteristics of Spatiotemporal Josephson Metasurfaces for Quantum Applications

Abstract

This presentation explores the various characteristics of a nonreciprocal, frequency-converting Josephson metasurface operating at millikelvin temperatures. Leveraging the unique properties of Josephson junctions, which support supercurrent flow without resistance, this metasurface enables efficient manipulation of nonlinear wave interactions, facilitating both frequency conversion and amplification of incident photons.

Figures (3)

• Figure 1: Nonreciprocal frequency conversion of spatiotemporal Josephson metasurface.
• Figure 2: Pure quantum frequency conversion by a space-time-modulated Josephson junction metasurface. (a) FDTD numerical simulation results for magnetic field distribution $H_y$. Normal excitation results in a highly efficient frequency conversion from $\omega_0=2\pi \times 3$ GHz to $\omega_0+\omega_\text{s}=2\pi \times 11.5$ GHz. (b) and (c) Frequency spectrum of the incident wave and the up-converted reflected wave at $\theta_\text{r}=135^\circ$, respectively.
• Figure 3: FDTD simulation of a space-time-modulated Josephson metasurface performing frequency mixing at $f_\text{s} = f_\text{0} = 1.5 \, \text{GHz}$, generating multiple harmonics from $2f_\text{s}$ to $8f_\text{s}$.