Spin blockade and phonon bottleneck for hot electron relaxation observed in n-doped colloidal quantum dots.

ABSTRACT: Understanding and manipulating hot electron dynamics in semiconductors may enable disruptive energy conversion schemes. Hot electrons in bulk semiconductors usually relax via electron-phonon scattering on a sub-picosecond timescale. Quantum-confined semiconductors such as quantum dots offer a unique platform to prolong hot electron lifetime through their size-tunable electronic structures. Here, we study hot electron relaxation in electron-doped (n-doped) colloidal CdSe quantum dots. For lightly-doped dots we observe a slow 1P_e hot electron relaxation (~10 picosecond) resulting from a Pauli spin blockade of the preoccupying 1S_e electron. For heavily-doped dots, a large number of electrons residing in the surface states introduce picosecond Auger recombination which an

SUBMITTER: Wang J 

PROVIDER: S-EPMC7822822 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature