biostudies-literatureLi YChinese Academy of SciencesNational Natural Science Foundation of Chinae2306518https://www.ebi.ac.uk/biostudies/studies/S-EPMC10966543biostudies-literatureUnknown11(12)Colloidal semiconductor nanoplatelets (NPLs) have emerged as low-cost and free-standing alternates of traditional quantum wells. The giant heavy- and light-hole splitting in NPLs allows for efficient optical spin injection. However, the electron spin lifetimes for prototypical CdSe NPLs are within a few picoseconds, likely limited by strong electron-hole exchange in these quantum- and dielectric-confined materials. Here how this hurdle can be overcome with engineered NPL-heterostructures is demonstrated. By constructing type-I CdSe/ZnS core/shell NPLs, dielectric screening inside the core is strongly enhanced, prolonging the electron spin polarization time (τ_esp) to over 30 ps (or 60 ps electron spin-flip time). Alternatively, by growing type-II CdSe/CdTe core/crown NPLs to spatially separate electron and hole wavefunctions, the electron-hole exchange is strongly suppressed, resulting in τ_esp as long as 300 ps at room temperature. This study not only exemplifies how the well-established synthetic chemistry of colloidal heterostructures can aid in spin dynamics control but also establishes the feasibility of room-temperature coherent spin manipulation in colloidal NPLs.Advanced science (Weinheim, Baden-Wurttemberg, Germany)Dielectric and Wavefunction Engineering of Electron Spin Lifetime in Colloidal Nanoplatelet Heterostructures.PMC1096654322203090YSBR-007YSBR‐007Wu KLi YZhu JXiang DWang LfalseDielectric and Wavefunction Engineering of Electron Spin Lifetime in Colloidal Nanoplatelet Heterostructures.Colloidal semiconductor nanoplatelets (NPLs) have emerged as low-cost and free-standing alternates of traditional quantum wells. The giant heavy- and light-hole splitting in NPLs allows for efficient optical spin injection. However, the electron spin lifetimes for prototypical CdSe NPLs are within a few picoseconds, likely limited by strong electron-hole exchange in these quantum- and dielectric-confined materials. Here how this hurdle can be overcome with engineered NPL-heterostructures is demonstrated. By constructing type-I CdSe/ZnS core/shell NPLs, dielectric screening inside the core is strongly enhanced, prolonging the electron spin polarization time (τ_esp) to over 30 ps (or 60 ps electron spin-flip time). Alternatively, by growing type-II CdSe/CdTe core/crown NPLs to spatially separate electron and hole wavefunctions, the electron-hole exchange is strongly suppressed, resulting in τ_esp as long as 300 ps at room temperature. This study not only exemplifies how the well-established synthetic chemistry of colloidal heterostructures can aid in spin dynamics control but also establishes the feasibility of room-temperature coherent spin manipulation in colloidal NPLs.2024-01-01T00:00:00Z2024 Mar2025-04-25T21:39:34.887Z2025-04-06T08:47:17.352ZS-EPMC109665433823423810.1002/advs.202306518