Tunable quantum two-photon interference with reconfigurable metasurfaces using phase-change materials

Abstract

The ability of phase-change materials to reversibly and rapidly switch between two stable phases has driven their use in a number of applications such as data storage and optical modulators. Incorporating such materials into metasurfaces enables new approaches to the control of optical fields. In this article we present the design of novel switchable metasurfaces that enable the control of the nonclassical two-photon quantum interference. These structures require no static power consumption, operate at room temperature, and have high switching speed. For the first adaptive metasurface presented in this article, tunable nonclassical twophoton interference from -97.7% (anti-coalescence) to 75.48% (coalescence) is predicted. For the second adaptive geometry, the quantum interference switches from -59.42% (anticoalescence) to 86.09% (coalescence) upon a thermally driven crystallographic phase transition. The development of compact and rapidly controllable quantum devices is opening up promising paths to brand-new quantum applications as well as the possibility of improving free space quantum logic gates, linear-optics bell experiments, and quantum phase estimation systems.

Polarization coincidence images from metasurfaces with HOM-type interference

“…We further note that here the images with HOM interference are obtained via the design of the metasurface. It can be via the capability of tailoring either spatial modes and also polarization in this work (Li et al, 2021;Estakhri and Norris, 2021). In terms of the second-order coherence g 2 (termed as coincidence signal hereafter) between a pixel in the left image and another pixel in the right image, we expect to observe a dip in scanning Dt (e.g., anticorrelated photon between X 1 and X 2 in Figure 1).…”

“…For the case with interference, metasurface-based HOM interference has been demonstrated using non-classical light, including the use of multiphoton interference for state reconstruction (Wang et al, 2018a), and the demonstration of metasurface interferometry with polarization-entangled photons (Georgi et al, 2019) and spatial modes (Li et al, 2021). The possibility of tunable two-photon interference is also investigated in (Estakhri and Norris, 2021) by introducing reconfigurable metasurface using phase-change materials.…”

“…Such combination will be potentially useful for further developing quantum imaging schemes, e.g. Ndagano et al, (2021), in the future, or can be further extended to use tunable metasurfaces (Estakhri and Norris, 2021). Figure 1 shows our scheme of generating coincidence images from a metasurface, which is applicable with either a singlephoton source (quantum) or phase-randomized weak coherent light source (classical) as we will develop and show toward the last part of the current work.…”

Emerging Trend in Unconventional Metasurfaces: From Nonlinear, Non-Hermitian to Nonclassical Metasurfaces

“…On the other hand, utilizing phase change materials is another way to control the quantum state. Estakhri et al . demonstrated the possibility of GeTe-based metasurface to manage two-photon quantum interference.…”

Region-specified inverse design of absorption and scattering in nanoparticles by using machine learning

“…While the number of parameters may not be as large as the topology optimization scenarios, simultaneously satisfying multiple objectives within a typically constrained parameter space is not a simple task [1]. Nonetheless, parameter optimization and tuning has been extensively explored in the inverse design of electromagnetic devices [15][16][17][18][19]. Indeed, given the complexity of typical photonic structures, the number of tuning parameters may not be small even for a predetermined geometry.…”