Figure 3: Auger-heating induced slow hot-carrier cooling at high carrier densities.
From: Slow cooling and highly efficient extraction of hot carriers in colloidal perovskite nanocrystals
(a) Energy loss rate vs carrier temperature Tc for MAPbBr3 NCs with <N0> around 2.5 and MAPbBr3 bulk film with n0 around 1.5 × 1019 cm-3. Solid green line represents the LO–phonon model at low carrier densities. (b) Auger recombination lifetimes and hot-carrier cooling time versus perovskite NC volume. Black and red dashed lines are guides to the eye showing the scaling of the lifetimes with the square root of NC volume. Inset illustrates the hot-carrier re-excitation by Auger recombination of carriers at band edge (also known as Auger heating). Error bars on the x axis account for the size distribution of NCs and on the y axis represent uncertainty in the determination of the lifetime. (c) Normalized hot-carrier decay at different pump fluences. Solid lines are bi-exponential decay fits. Photoexcitation energy for a–c is 3.1 eV.
