Local photonic density of states in hyperbolic metasurfaces

Abstract

In this work, we design and study an optical hyperbolic metamaterial of a few layers (i.e. metasurface), with a specific in-plane dispersion relationship that has a transition from open hyperbolic type I to type II. We will show that although there is no longer a topological transition from a closed curve to an open hyperbola in dispersion relationship, the local photonic density of state (PDOS) still can be significantly enhanced around the transition point, due to epsilon-near-zero (ENZ) modes. We also show a finite-size effect, which leads to the PDOS enhancement that is strongly dependent on the top layer of material. It is found a balance between the ENZ modes and surface plasmon polaritons for PDOS enhancement. Our results provide some insights for enhancing light–matter interactions via hyperbolic metasurfaces.

Ultrahigh-Efficiency Thermal Rectification via Topological Transition of Photonic Density of States and Near-Field Radiation Gap Variations

“…Based on the aforementioned results, we more closely evaluate to the material properties in the frequency range of 1.5 × 10 14 −1.8 × 10 14 rad/s by effective media theroy. 2 For TEM terminals composed of SiC/PDMS multilayer structure, there is no phase change in both cases of forward/reverse biases, and within the aforementioned frequency band, their effective dielectric function always maintains hyperbolic properties and has an ENZ transition point, as shown in Figure 4d. For the MIT terminal, when SiC and VO 2 overlap to form a multilayer structure, with forward temperature bias, the VO 2 is in an insulating state.…”

“…To demonstrate that the hyperbolic mode-enhanced heat transfer proposed in the NFRTR is induced by the phase change of the artificially constructed multilayer structure rather than excited by the material itself, Figure d–f shows the dielectric function variation with angular frequency for TEM and MIT terminals under forward and reverse biases. Based on the aforementioned results, we more closely evaluate to the material properties in the frequency range of 1.5 × 10 14 –1.8 × 10 14 rad/s by effective media theroy . For TEM terminals composed of SiC/PDMS multilayer structure, there is no phase change in both cases of forward/reverse biases, and within the aforementioned frequency band, their effective dielectric function always maintains hyperbolic properties and has an ENZ transition point, as shown in Figure d.…”

“…Advances in nanotechnology have made it possible to manufacture artificial microstructures at a variety of subwavelength scales that have reasonably designed properties not available from natural materials. − It promotes research on the experimental and theoretical behaviors of near-field radiation heat transfer, − among which active control of heat transport at the nanoscale is vital for various applications, and the key component for achieving thermal control in solid-state devices is the thermal rectifier . Similar to an electric diode, which has unidirectional conductivity in electronic devices, a thermal rectifier or thermal diode is defined as a unidirectional thermal transporter and has been widely used in energy conversion, thermal logic calculations, and thermal management .…”

Selectively Strong Coupling of MoS2 Excitons to a Metamaterial at Room Temperature

“…2(d). The PDOS is directly proportional to the electric field (E) [37]. So the ratio of HMM electric field at B (2.0222 eV) to A (1.8463 eV) exciton position is given by…”

Near-Field Radiative Heat Transfer between Disordered Multilayer Systems

“…However, this is not always the case. [39,40] In this Letter, we introduce disorder into the multilayer heat transfer system for the first time to explore its influence on heat transfer. By comparing the filling ratio, we find that disorder has a strong and non-negligible regulating effect on heat transfer.…”