Fig. 5: Dynamic control of electroluminescence (EL) from cavity-integrated semiconducting carbon nanotube (sCNT).

a Simulated spectrum of light coupled out from one of the ends the cross-bar photonic crystal (PhC) cavity. The symmetric design of the PhC cavity leads to equal EL emission at both sides. b U_sd-U_g curve acquired at constant sCNT biasing current I_sd = −90 nA. Forward and backward sweep traces are shown. The yellow area corresponds to the regime, in which the excitonic EL emission is in the switched-on state. The red point corresponds to the electric acquisition point of the spectrum (red curve) shown in (d). c Measured dependence of full-bandwidth coupling efficiency β_int on I_sd biased sCNT for several PhC devices. d The spectrum of EL sCNT coupled to the fundamental resonance mode at 1438.1 nm, acquired from coupler C of a PhC cross-bar device gated with gate-voltage U_g = 20 V (EL switched-on state, red curve) and at U_g = 0 V (EL switched-off state, blue curve). The spectrum of free-space EL simultaneously recorded at the position of the sCNT coupled to the cavity in the switched-on state at U_g = 20 V of the same investigated device is shown by the green curve. sCNT biasing current is I_sd = −90 nA. e EL excitation map of enhanced EL intensity integrated over the fundamental resonance mode (1430–1450 nm) outcoupled from coupler C of explored device as a function of driven source-drain current I_sd and gate voltage U_g. f Measured dependence of full-bandwidth enhancement-factor F_int on I_sd applied to the sCNT for three cross-bar PhC devices, acquired at 77 K. Device 1 consists of N = 25 segments in each Bragg mirror with a lattice period of a = 462 nm; device 2: N = 35, a = 460 nm; device 3: N = 35, a = 455 nm. All data recorded at 77 K.