Twist-induced control of near-field thermal radiation in multilayered black phosphorus/vacuum system

Modulating the photonic transmission coefficient (PTC) is a critical factor in regulating the near-field radiative heat transfer (NFRHT) between two objects. Extending previous studies, we find that multiple body-vacuum interfaces can support various resonance modes and flexibly amplify the PTC. We show that black phosphorus (BP)/vacuum multilayers support coupled multiple anisotropic surface plasmon polaritons (MASPPs) and propose a theoretical model of a pattern-free noncontact thermal modulator based on the mechanical twist between two BP/vacuum multilayer structures. The various symmetric and antisymmetric branches of MASPPs strengthens the PTC, and with it the NFRHT. We also analyze the combined effects of the number of layers and twisted angle. Changing the integral twisted angle and inter-layer twisted angle modulates the positions and intensities of MASPPs. In addition to the twist between the emitter and receiver, the inter-layer twist gives the BP/vacuum multilayer heat transfer system another pathway to modulate the NFRHT. These results pave the way for using two-dimensional anisotropic materials to actively manipulate heat currents.