Asset Details
Do you wish to reserve the book?
Structural fluctuations cause spin-split states in tetragonal (CH^sub 3^NH^sub 3^)PbI^sub 3^ as evidenced by the circular photogalvanic effect
Hey, we have placed the reservation for you!
By the way, why not check out events that you can attend while you pick your title.
Oops! Something went wrong.
Looks like we were not able to place the reservation. Kindly try again later.
Are you sure you want to remove the book from the shelf?
Structural fluctuations cause spin-split states in tetragonal (CH^sub 3^NH^sub 3^)PbI^sub 3^ as evidenced by the circular photogalvanic effect
Do you wish to request the book?
Structural fluctuations cause spin-split states in tetragonal (CH^sub 3^NH^sub 3^)PbI^sub 3^ as evidenced by the circular photogalvanic effect
Please be aware that the book you have requested cannot be checked out. If you would like to checkout this book, you can reserve another copy
We have requested the book for you!
Your request is successful and it will be processed during the Library working hours. Please check the status of your request in My Requests.
Oops! Something went wrong.
Looks like we were not able to place your request. Kindly try again later.
Journal Article
Structural fluctuations cause spin-split states in tetragonal (CH^sub 3^NH^sub 3^)PbI^sub 3^ as evidenced by the circular photogalvanic effect
2018
Overview
Lead halide perovskites are used in thin-film solar cells, which owe their high efficiency to the long lifetimes of photocarriers. Various calculations find that a dynamical Rashba effect could significantly contribute to these long lifetimes. This effect is predicted to cause a spin splitting of the electronic bands of inversion-symmetric crystalline materials at finite temperatures, resulting in a slightly indirect band gap. Direct experimental evidence of the existence or the strength of the spin splitting is lacking. Here, we resonantly excite photocurrents in single crystalline (CH3NH3)PbI3 with circularly polarized light to clarify the existence of spin splittings in the band structure. We observe a circular photogalvanic effect, i.e., the photocurrent depends on the light helicity, in both orthorhombic and tetragonal (CH3NH3)PbI3. At room temperature, the effect peaks for excitation photon energies ΔE=110 meV below the direct optical band gap. Temperature-dependent measurements reveal a sign change of the effect at the orthorhombic–tetragonal phase transition, indicating different microscopic origins in the two phases. Within the tetragonal phase, both ΔE and the amplitude of the circular photogalvanic effect increase with temperature. Our findings support a dynamical Rashba effect in this phase, i.e., a spin splitting caused by thermally induced structural fluctuations which break inversion symmetry.
