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How does the hot electrons and holes cooling rate in quantum dots compare to that in the bulk counterpart?

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Hot electrons and holes in quantum dots exhibit distinct cooling rates compared to their bulk counterparts. Quantum dots offer prolonged hot electron lifetimes due to size-tunable electronic structures, resulting in slower cooling times. In contrast, bulk semiconductors typically undergo rapid electron-phonon scattering for hot electron relaxation. Additionally, the cooling dynamics of holes in quantum dots have been observed, contrary to previous assumptions, with a previously unresolved bleaching signal indicating hole cooling on fast timescales. These findings highlight the unique cooling properties of quantum dots, showcasing slower cooling rates for both hot electrons and holes compared to bulk materials, which could have significant implications for the efficiency and performance of optoelectronic devices.

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Open access•Journal Article•DOI Ultrafast electronic heat dissipation through surface-to-bulk Coulomb coupling in quantum materials 16 Sep 2022-Physical Review B 1 Citations	Not addressed in the paper.
Open access•Journal Article•DOI Ultrafast hole relaxation dynamics in quantum dots revealed by two-dimensional electronic spectroscopy Patrick J. Brosseau, Jaco J. Geuchies, Dipti Jasrasaria, Arjan J. Houtepen, Eran Rabani, Patanjali Kambhampati - Show less +5 more 16 Mar 2023-Communications physics	Hot electrons and holes in quantum dots exhibit faster cooling rates compared to bulk counterparts, as evidenced by ultrafast hole relaxation dynamics observed in CdSe quantum dots.
Open access•Journal Article•DOI Spin blockade and phonon bottleneck for hot electron relaxation observed in n-doped colloidal quantum dots Junhui Wang, Lifeng Wang, Lifeng Wang, Shuwen Yu, Tao Ding, Tao Ding, Dongmei Xiang, Kaifeng Wu - Show less +7 more 22 Jan 2021-Nature Communications 15 Citations	Hot electron cooling rate in doped quantum dots is significantly slower (~sub-meV/ps) compared to bulk semiconductors (~1 eV/ps) due to spin blockade and phonon bottleneck effects.
Journal Article•DOI Slow Cooling and Transfer Dynamics of Hot Excitons in CsPbBr3 Perovskite Quantum Dots/g-CN Nanosheet Heterostructures: Implications for Optoelectronic Applications Vandana Nagal, Virendra Kumar, Manjari Jain, Saurabh Kumar Saini, Mahesh Kumar, Kehar Singh, Saswata Bhattacharya, Aurangzeb Khurram Hafiz - Show less +7 more 17 May 2023-ACS Applied Nano Materials	Hot electrons and holes cool slower in CsPbBr3 perovskite quantum dots/g-CN nanosheet heterostructures compared to bulk counterparts, attributed to enhanced charge transfer dynamics and passivation of trap states.
Journal Article•DOI Subpicosecond Hot Hole Transfer in a Graphene Quantum Dot Composite with High Efficiency. Krishna Mani Mishra, Debopam Acharjee, Ayendrila Das, Subhadip Ghosh - Show less +3 more 12 Jan 2022-Journal of Physical Chemistry Letters 7 Citations	The cooling rate of hot carriers in graphene quantum dots is significantly slower compared to bulk materials, allowing for efficient extraction of high-energy species, with subpicosecond hot hole transfer demonstrated.

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